new this symposium marks the 60th birthday professor dr. todd b. … · 2015. 11. 12. ·...

This Symposium marks the 60th Birthday and the 30-Year Academic Career of

Professor Dr. Todd B. Marder

Advances in Organic and Inorganic CHEMISTRY Enhancing International COOPERATION

Institut für Anorganische Chemie, Universität Würzburg, 16 November 2015

Symposium Information v

FOREWORD

It is a real honour for me to say a few introductory words to the participants of

the symposium dedicated to the 60th birthday of Professor Todd B. Marder.

After first meeting Todd at the University of California at Los Angeles in the

early 1980s, when he was about to obtain his Ph.D., I carefully followed his

professional career and became steadily impressed by the results and the

impact of his work. Therefore, it was good luck that we succeeded in 2012 to

bring him from the Chair in Inorganic Chemistry at the University of Durham in

the UK to our University, and not only me, but also my colleagues, realised

quite soon that it was the best thing we could do. His coming was not only a

gift for the Institute of Inorganic Chemistry, of which I was the head for 27

years, but for the whole Department and above all for the Faculty. While it was

common already in my time that guest scientists and postdocs were visiting

the Institute and working in our labs, Todd brought a new international flair to

the students and the staff owing to his various cooperations and contacts with

individuals and groups from nearly all over the world. The people coming to

the symposium provide clear evidence for this.

I wish all the participants of the symposium a wonderful and successful stay

at our University, where exactly 120 years ago Conrad Röntgen discovered

the X-ray, and I hope that they bear in mind that the city of Würzburg is also

well worth visiting.

Prof. Dr. Dr. h.c. Helmut WERNER

Professor Emeritus of Inorganic Chemistry



Symposium Information vii

TABLE OF CONTENTS

Foreword – Prof. Dr. Dr. h.c. Helmut WERNER (Emeritus)............................................................................. v

Table of Content ......................................................................................................................................... vii

SYMPOSIUM INFORMATION

General Information

The Symposium ............................................................................................................................... xi

The Organisation .............................................................................................................................. xii

The People ....................................................................................................................................... xiii

The Sponsors ................................................................................................................................... xiv

The Catalysts .................................................................................................................................... xv

Symposium Mixer – Foyer of the Neubaukirche ............................................................................................. xvi

Symposium Day – Zentralbau Chemie, Am Hubland ..................................................................................... xviii

Symposium Program

Schedule of Lectures ........................................................................................................................ xx

Location of Posters ........................................................................................................................... xxii

Location of Exhibitors ....................................................................................................................... xxv

ABSTRACTS

Invited Lectures ............................................................................................................................................... 3

Invited Posters ................................................................................................................................................ 23

Institute of Inorganic Chemistry Research-Groups Posters ............................................................................ 39

Marder Research Group Posters .................................................................................................................... 51

SYMPOSIUM INFORMATION



Symposium Information xi

GENERAL INFORMATION – The Symposium

Symposium Activities for the Invited Guests – 15 November 2015

Würzburg City Tour (14:00 – 16:00) provided by:

Mr. Rudi HELD (http://www.rudis-kunstgeschichten.de/)

Glühwein tasting and refreshments (16:00 – 19:30) provided by:

Standard (http://www.standard-wuerzburg.com/)

Symposium Mixer – 15 November 2015

18:00 – 20:00

Foyer of the Neubaukirche

Domerschulstraße, Würzburg 97070

Welcoming Address by Prof. Dr. Christoph LAMBERT

Dean of the Fakultät für Chemie und Pharmazie

Catering provided by:

Feinschmecker's (http://www.feinschmecker-s.de/)

Music provided by:

Mr. Gerd SEMLE (http://www.gerdsemle.de/index.html)

Symposium Day – 16 November 2015

08:40 – 20:00 (registration desk opens at 08:00)

Zentralbau Chemie, Hörsaal A,

Campus Hubland Süd

Universität Würzburg, Würzburg 97074

Lunch served at:

Restaurant Hubland (http://restaurant-hubland.de/)

E-mail: [email protected]

Telephone: +49 (0) 931 / 31-83308

Symposium Website: www.toddmardersymposium.com



xii Symposium Information

GENERAL INFORMATION – The Organisation

Symposium Coordinator: Ms. Anne BRUNELLE

Symposium Secretaries: Ms. Bianca PUTZ, Ms. Cornelia WALTER

Local Organising Comittee:

Prof. Dr. Todd B. MARDER

Prof. Dr. Holger BRAUNSCHWEIG

Dr. Stefan WAGNER (administration)

Ms. Alexandra FRIEDRICH, Ms. Amanda NELSON (activities)

Ms. Ruth RADIUS, Ms. Sabine LORENZEN (catering)

The Marder Research Group

External Consultants:

Prof. Seth MARDER, Georgia Institute of Technology

Dr. Edward ROBINS, Singapore Bioimaging Consortium

Website:

Design and Administration: Ms. Anne BRUNELLE

Technical Assistance: Mr. Daniel HACCOUN

Proofreading and Fact-Checking: Mr. Klaus HÜNIG, Ms. Helga DIETTRICH

Program & Abstracts Book:

Concept and Layout: Ms. Anne BRUNELLE

Technical Assistance: Ms. Ellen KLAUS

Graphics: Mr. Uli GRAMLICH

Proofreading: Prof. Dr. Todd B. MARDER, Dr. Shubhankar K. BOSE, Dr. Emily NEEVE

Translation & Interpretation: Ms. Claudia KAMMLER, Mr. Uli GRAMLICH



Symposium Information xiii

GENERAL INFORMATION – The People

We wholeheartedly thank the following persons for their contribution to the organisation of this Symposium. They have provided invaluable assistance, support, advice and encouragement. They constitute a striking example of what teamwork and cooperation can achieve.

Shubhankar BOSE Johannes BRAND Simon BRAND Holger BRAUNSCHWEIG Rian DEWHURST Helga DIETTRICH Martin ECK Alexandra FRIEDRICH Uli GRAMLICH Stefanie GRIESBECK Martin HÄHNEL Thomas HERDMANN Hildegard HOLZINGER Klaus HÜNIG Benjamin HUPP Lei JI Claudia KAMMLER Ellen KLAUS Beate KRAUS Carsten LENCZYK Xiaocui LIU Sabine LORENZEN Christoph MAHLER Lujia MAO Seth MARDER Julia MERZ Wenbo MING

Roberto MOLTENI Emily NEEVE Amanda NELSON Jörn NITSCH Wolfgang OBERT Sabrina PIETSCH Bianca PUTZ Ruth RADIUS Udo RADIUS Florian RAUCH Sebastian REUTER Edward ROBINS Charlotte SCHEUFLER Carl SCHILLER Claudia SCHÜRGER Julia SCHUSTER Nicola SCHWENK Jens SEUFERT Alfred SCHERTZER Carolin SIECK Marco STANOPPI Stephan WAGNER Conny WALTER Chang-Yiang YAO Birgit ZEPKE Jing ZHOU

In addition, we are thankful to all the people in the various administrive departments at the Universität Würzburg for their help in making this event possible. Sincere apologies to those we may have forgotten...



xiv Symposium Information

GENERAL INFORMATION – The Sponsors

The following companies and organisations have financially supported this Symposium.

Nobel Gas Level (our main sponsor):

Precious Metal Level:

Main Group Level:



Symposium Information xv

GENERAL INFORMATION – The Catalysts

The following organisations have contributed directly or indirectly to this Symposium.



xvi Symposium Information

SYMPOSIUM MIXER – Foyer of the Neubaukirche

The Neubaukirche In 1582, Catholic Prince-Bishop Julius Echter von Mespelbrunn ordered the construction of a central university building – die Alte Universität, together with its own church – die Neubaukirche. Georg Robin, an architect from Mainz, was chosen for the task. On 8 September, 1591, the university church was solemnly consecrated. It is built in Renaissance style and houses a Shucke organ, the second in size after that of the Würzburg Cathedral. At 91 meters in height, it has the highest steeple in the City and is illuminated at nightfall. In 2005, it was fitted with a carillon. Over the centuries, the Neubaukirche underwent several phases of renovations and re-decoration. On 16 March, 1945, it suffered the same fate as the rest of the City and was almost completely destroyed by bombs. The debris were cleared by the end of 1946 and the church was fitted with a makeshift roof. In the late 1960s, the University launched a series of fundraisers to gather the funds necessary to complete the rebuilding. On 7 November, 1985, the church was finally reopened. Today, the Neubaukirche is a venue for assemblies, graduation ceremonies, concerts, etc. The Symposium Mixer will take place in the Foyer of the Neubaukirche, which is often used for more informal events.



Symposium Information xvii

SYMPOSIUM MIXER – Foyer of the Neubaukirche (cont.)

Sunday, 15 November, 2015

18:00-20:00

A short welcoming address will be delivered by Prof. Dr. Christoph LAMBERT, Dean of the Fakultät für Chemie und Pharmazie

Refreshments will be served

On the night, you can pick up your Symposium information bag at the Registration Desk

Access The entrance to the Foyer of the Neubaukirche is in the courtyard of the Alte Universität and is accessible through an arched portal located on Domerschulstraße (see photographs on previous page and map below). Signs will be posted near the entrance. The venue is a short walk away from the Market Place and the Cathedral. The closest parking facility is in front of the Residenz Würzburg on the Balthasar-Neumann-Promenade. Parking on the surrounding streets is possible, but difficult.



xviii Symposium Information

SYMPOSIUM DAY – Zentralbau Chemie, Am Hubland

Monday, 16 November 2015

08:40-20:00

The Registration Desk will open at 08:00 Access by public transportation

By train: Deutsche Bahn offers an excellent service to Würzburg. To obtain arrival and departure times, see the DB website (www.bahn.com/i/view/GBR/en/).

By bus: from Würzburg main train/bus station (Hauptbahnhof): - Bus no. 114, bus stop “Universitätszentrum” - Bus no. 214, bus stop “Hubland/Mensa” The fare is 2,50 euro and can be paid on the bus (correct change recommended).

By taxi: from the bus/train station and the city center, the fare is approximately 15 euros, more if there is a lot of trafic.

https://toddmardersymposium.files.wordpress.com/2015/08/toddmardersymposium-hubland.jpg



Symposium Information xix

SYMPOSIUM DAY – Zentralbau Chemie, Am Hubland (cont.) Access by car See the map below. Parking is free and readily available early in the morning. Persons with disabilities are permitted to park directly at the south entrance of the main library. This entrance is suitable for use by disabled persons.

https://toddmardersymposium.files.wordpress.com/2015/08/toddmardersymposium-hubland21.jpg



xx Symposium Information

SYMPOSIUM PROGRAM – Schedule of Lectures

08:00-08:40 REGISTRATION

08:40-08:50 Prof. Dr. Holger BRAUNSCHWEIG – Welcoming Address –

Chairing the Session: Prof. Dr. Klaus MÜLLER-BUSCHBAUM

08:50-09:10 Prof. Patrick STEEL, Durham University, U.K. Enhancing the Borylation Experience: Extending and Applying Ir-Catalysed C-H Borylation

09:10-09:30 Prof. Webster SANTOS, Virginia Tech, U.S.A. Copper-Catalyzed Borylation of Alkenes: Towards Sustainable Chemistry

09:30-09:50 Prof. Kálmán J. SZABÓ, University of Stockholm, SWEDEN Transition Metal Catalyzed C-H Borylation of Alkenes

09:50-10:10 Dr. Christian KLEEBERG, T.U. Braunschweig, GERMANY Boron-Element Compounds: From Cu(I) Catalysis to Boryl Complexes

10:10-10:50 COFFEE BREAK

Chairing the Session: Prof. Dr. Maik FINZE

10:50-11:10 Prof. Paul LOW, University of Western Australia, AUSTRALIA Building Bridges: New Aspects of the Chemistry and Spectroscopic Properties of ‘Mixed-Valence’ Complexes

11:10-11:30 Dr. Edward ROBINS, Singapore Bioimaging Consortium, SINGAPORE Palladium-Mediated Organometallic Chemistry of [18F]Fluorinated Intermediates for the Preparation of Radiolabeled Imaging Probes for Positron Emission Tomography (PET)

11:30-11:50 Prof. Ashok KAKKAR, McGill University, CANADA Designing Adaptive Nanostructures for Multi-tasking in Nanomedicine

11:50-12:10 Prof. Zhenyang LIN, H.K.U.S.T., HONG KONG Computational Insight into Mechanism of Nickel-Catalyzed Reductive Carboxylation of Styrenes Using CO2

12:10-14:00 LUNCH



Symposium Information xxi

SYMPOSIUM PROGRAM – Schedule of Lectures (cont.)

Chairing the Session: Prof. Dr. Ulrich SCHATZSCHNEIDER

14:00-14:20

Prof. Seth R. MARDER, Georgia Tech, U.S.A.

Advances, Challenges and Opportunities for Direct C-H Bond Functionalization in

Materials Chemistry

14:20-14:40 Dr. Shigeru SHIMADA, A.I.S.T., JAPAN

Organodibismuthines: Unique Reactivity and Application in Organic Synthesis

14:40-15:00 Prof. Dr. Uwe H. F. BUNZ, Universität Heidelberg, GERMANY

N-Heteroacenes: Syntheses and Properties as Electron Transport Materials

15:00-15:20 Prof. Jingping ZHANG, Northeast Normal University, CHINA

Mechanistic Understanding Towards Economic Synthesis of Pyrrole Derivatives

15:20-16:00 COFFEE BREAK

Chairing the Session: Prof. Dr. Udo RADIUS

16:00-16:20

Prof. Ian D. WILLIAMS, HKUST, HONG KONG

From Resolving to use Boron to Resolving with Boron: Spiroborate Anions for

Crystallization and Chiral Separation

16:20-16:40 Prof. Dr. Matthias WAGNER, Universität Frankfurt-am-Main, GERMANY

Boron-Doped Graphene Flakes

16:40-17:00 Dr. Jean-François HALET, Université de Rennes I, FRANCE

Sixty Reasons to Study Sixty Compounds with a Friend Who’s Sixty

17:20-17:40 Prof. Dr. Holger BRAUNSCHWEIG, Universität Würzburg, GERMANY

Boron-Boron-Bonds: Unexpected Results and New Insights

17:40-18:00 Prof. Dr. Todd B. MARDER

– A Few Short Remarks –

18:00-20:00 POSTER SESSION



xxii Symposium Information

SYMPOSIUM PROGRAM – Posters

INVITED POSTERS

1. Prof. Graeme HOGARTH - Bioinspired Catalysis: Low-Valent Iron Clusters as Efficient Electrocatalysts for

Clean Hydrogen Production

2. Ms. Audrey LEDOUX - Polyboramines as Hydrogen Reservoirs

3. Dr. Scott COLLINS - Modification of Methylaluminoxane as Studied by Electrospray Ionization Mass

Spectrometry (ESI MS); Does the Dog Wag the Tail or Vice Versa?

4. Prof. Ibraheem A. MKHALID - Synthesis and Molecular Structures of Palladium(II) Complexes Containing

Monodentate Phenylpyridine Derivatives and Their Activity in Suzuki Reactions

5. Prof. Marie-Hélène THIBAULT - Characterization of a New Shrimp Oil from Pandalus Borealis Produced in

New Brunswick, Canada

6. Ms. Julia K. SCHUSTER - Beryllium Joins the Game: Synthesis of Novel Linear Beryllium Complexes



Symposium Information xxiii

SYMPOSIUM PROGRAM – Posters (cont.)

INVITED POSTERS (cont.) 7. Ms. Ulrike WAIS - Nanoformulation of Poorly Water-Soluble Drugs with the Aid of Branched Polymers

8. Prof. Tolulope FASINA - Absorption and Emission Properties of Schiff Bases Derived from Diphenylacetylenes 9. Prof. Zhiqiang LIU - Functionalize Pyrene at Electrophilic Unfavorable Positions to Build Regioisomeric Thienoacenes as OFET Materials 10. Prof. Dongxia ZHU - New AIE-Active Dinuclear Ir(III) Complexes with Reversible Piezochromic Phosphorescence Behaviour 11. Prof. Kittiya WONGKHAN - Highly Efficient Blue LECs Using Charged Iridium Complexes 12. Mr. Marco STANOPPI - First Forays into the Investigation of Cu(I) Complexes as Sensitizers in Photocatalysis 13. Prof. Xunjin ZHU - Design and Synthesis of New Porphyrin-Centered Small Molecules for Photovoltaic Applications

INORGANIC INSTITUTE RESEARCH-GROUPS POSTERS 14. Dr. Rian DEWHURST, on behalf of the Staff and Students of the Institute - Inorganic Chemistry in

Würzburg: A Hub of Local, National and International Research Networks

15. Prof. Dr. Holger BRAUNSCHWEIG - Research Interests of the Braunschweig Group

16. Prof. Dr. Maik FINZE - Fluorinated and Boron-Based Building Blocks – From Molecules to Materials

17. Prof. Dr. Ekkehard GEIDEL - Contexts – Everyday Questions Trigger the Motivation to Learn Chemistry

18. Dr. Viktoria H. GESSNER - The Organometallic Chemistry of Unusual Carbon Bases

19. Prof. Dr. Todd B. MARDER - Inorganic Chemistry with a Twist!

20. Prof. Dr. Klaus MÜLLER-BUSCHBAUM - Inorganic-Organic Hybrid Materials

21. Prof. Dr. Udo RADIUS - NHCs and Related Molecules in Main Group Element and Transition Metal

Chemistry

22. Prof. Dr. Ulricht SCHATZSCHNEIDER - Bioinorganic Chemistry: Bioorthogonal “click” Reactions for Quick

Access to Metal-Based Antiparasitic and Antitumor Drug Candidates

23. Prof. Dr. Reinhold TACKE - Research Group Prof. Dr. Reinhold Tacke



xxiv Symposium Information

SYMPOSIUM PROGRAM – Posters (cont.)

STEFFEN RESEARCH GROUP POSTERS 24. Mr. Jörn NITSCH - Why not Tetrahedral? A DFT Study on the Stability of d10-M(NHC)n Complexes

25. Mr. Roberto MOLTENI - On the Way to Luminescence: Synthesis of the First Stable Cu(I)-Phenylpyridine

Complexes

26. Mr. Benjamin HUPP - Highly Efficient Mechanochromic Luminescence of Structurally Simple Cu(I) NHC

Complexes

MARDER RESEARCH GROUP POSTERS

27. Dr. Alexandra FRIEDRICH - Single-Crystal Structure Determination from High-Pressure X-Ray Diffraction

Data

28. Mr. Mitzuho TSUCHIYA - Photochemical Properties of BODIPY-Imine Hybrids

29. Dr. Chang-Jiang YAO - Intermolecular Formyloxy-Arylation of Alkenes by Photoredox Meerwein Reaction

30. Dr. Shubhankar K. BOSE - Zinc-Catalyzed Borylation of Alkyl and Aryl Halides with Alkoxy Diboron

Reagents: An Efficient Synthetic Route to Alkyl and Aryl Boronates

31. Mr. Anthonius EICHHORN - Copper(I)-Catalyzed Suzuki-Miyaura Type Cross-Coupling Reactions

32. Ms. Amanda NELSON - Chemo-, Regio-, and Stereoselective Copper(II)-Catalyzed Conjugate Addition of

Bdan to Acetylenic Esters and Amides in an Aqueous Medium

33. Mr. Martin ECK - Copper-Catalyzed Borylation of Aryl Halides with Alkoxy Diboron(4) Reagents and

Reactivity Studies of Bis(ethylene glycolato)diboron (B2eg2)

34 Ms. Sabrina WÜRTEMBURGER-PIETSCH - Facile Ring Expansion Reactions of N-Heterocyclic Carbenes

with Diboron(4) Compounds

35. Dr. Emily C. NEEVE - Mechanistic Insight into Borylation Reactions with sp2-sp3 Anionic B2pin2 Adducts

36. Ms. Jing ZHOU - Nickel-Catalyzed Borylation of C-F Bonds

37. Mr. Lujia MAO - Highly Regioselective Allylic Borylation of Unactivated Alkenes: Allylic C-H

Functionalization at a Pd(IV) Center

38. Ms. Nicola SCHWENK - Seeing the Light: Reductive Coupling of Diarylundecatetraynes with [Rh(η2-

S2CNEt2)(PPh3)2] and [Rh(η2-S2CNEt2)(PMe3)2] Generates a Variety of Luminescent Materials

39. Ms. Carolin SIECK - The Light at the End of the Cycle: Reductive Coupling of Diynes at Rhodium Gives

Fluorescent Rhodacyclopentadienes or Phosphorescent Dibenzorhodacyclopentadienes

40. Dr. Martin HÄHNEL - Unusual Reactivity Gives Unusual Chromophores – From [3+2] Cycloaddition

Products to Highly Substituted Azulenes via Pt(II) Catalysis

41. Dr. Lei JI & Ms. Julia MERZ - Communication Between Pyrene and Substituents at its 2- and 7- Positions:

Altering the Fundamental Frontier Molecular Orbital Ordering of Pyrene

42. Ms. Stefanie GRIESBECK - 3-Coordinate Boron π-Acceptors in Water-Soluble Chromophores for Live Cell

Imaging

43. Dr. Johannes BRAND - Taming the Beast: Stability Enhancement of Boroles By Incooperation of

Fluoromesityl Groups



Symposium Information xxv

SYMPOSIUM PROGRAM – Exhibitors

A. Universität Würzburg, Alexander von Humboldt Foundation, Erasmus, etc.

B. Inert

C. Linden CMS GmbH

D. Biotage Sweden AB

E. Novaled GmbH

F. Agilent Technologies

G. TCI Deutschland GmbH

ABSTRACTS

Invited Lectures



Invited Lectures 5

Holger BRAUNSCHWEIG Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland, 97074 Würzburg, GERMANY E-mail: [email protected]

Boron-Boron-Bonds: Unexpected Results and New Insights

Due to its inherent electron deficiency, boron prefers non-classical bonding regimes when combined in molecules with itself - in other words, boron forms polyhedral boranes, made up of multicenter bonds, rather than chains or rings with electron-precise boron-boron bonds. In the case of the latter, only very few well-defined examples have been published over the past decades, which all suffer from low-yielding, non-selective syntheses that solely rely on reductive coupling of amino(halo)boranes. Consequently, the area of classical boron-boron single and multiple bonds is relatively undeveloped. Over the past few years, we have put significant effort into the development of new synthetic strategies to overcome this seemingly element-specific deficiency. Here, results on the following topics will be presented:

Single Bonds – Recent Developments: Dehydrocoupling, Catenation and Hydroboration;

Double Bonds – Recent Developments: Base-Free Diborenes @ Platinum;

Triple Bonds – Recent Developments: Stabilization of B2 with CAACs: A Different Class of Molecules;

Reactivity Studies.



6 Invited Lectures

Uwe H. F. BUNZ Organisch-Chemisches Institut Universität Heidelberg Im Neuenheimer Feld 270, 69120 Heidelberg, GERMANY E-mail: [email protected]

N-Heteroacenes: Syntheses and Properties as Electron Transport Materials

In this contribution we demonstrate that the substitution of CH-groups by pyridine or pyrazine-type nitrogens leads to a significant stabilization of the frontier molecular orbitals, leading to an Umpolung of the hole transporting properties of the larger acenes such as pentacene. The azaacenes are fair to excellent electron transporting materials. We have developed several different synthetic routes that access azapentacenes, azahexacenes and also the first isolable diazapentacene. The routes include classic condensation reactions, nucleophilic aromatic substitution, direct alkynylation of heterocyclic quinones, and Pd-catalyzed coupling reactions of aromatic dihalides with aromatic diamines. This Pd-catalyzed coupling works under very mild conditions, if 2,3-dichloroquinoxalines or 2,3-dichlorobenzo[g]quinoxalines are employed, as the two halide substituents adjacent to the pyrazine subunit are highly activated towards this Pd-catalyzed Buchwald-Hartwig-type coupling. If un-activated ortho-dihalides are coupled, more stringent reaction conditions including more sophisticated Pd-sources are necessary to effect the reaction. However, a significant number of azaacenes up to diazaheptacenes can be made using this versatile method. The N-heteroacene story has been told in several review-articles, which we cite here: [1] U. H. F. Bunz. "The Larger Linear N-Heteroacenes". Acc. Chem. Res. 2015, 48, 1676. [2] U. H. F. Bunz. J. U. Engelhart, B. D. Lindner, M. Schaffroth: "Large N-Heteroacenes: New Tricks for Very Old Dogs?". Angew. Chem. Int. Ed. 2013, 52, 3810. [3] U. H. F. Bunz. "The Larger N-Heteroacenes". Pure Appl. Chem. 2010, 82, 953. [4] U. H. F. Bunz. "N-Heteroacenes". Chem. Eur. J, 2009, 15, 6780.



Invited Lectures 7

Jean-François HALET Institut des Sciences Chimiques de Rennes UMR 6226 CNRS-Université de Rennes 1 Avenue du Général Leclerc, 35042 Rennes, FRANCE E-mail: [email protected] Sixty Reasons to Study Sixty Compounds with a Friend Who’s Sixty

Over the years collaborative interactions between Marder and Halet’s groups have aimed to link the experimental results (Marder) closely with those of theoreticians (Halet) in order to arrive at detailed understanding of the electronic structure and potential applications of specific conjugated systems, which display many remarkable properties, such as luminescence.[1-7] History of this collaboration will be painted using specific portraits chosen among three-coordinate boron molecules and diyne complexes. In particular, it will be shown how the DFT machinery can be used in synergy with experiments to calculate molecular structures, energies, as well as UV-Vis absorption properties of these systems. References: [1] Z. Yuan, J. C. Collings, N. J. Taylor, T. B. Marder, C. Jardin, J.-F. Halet. J. Solid State Chem. 2000, 154, 5. [2] Z. Yuan, C. D. Entwistle, J. C. Collings, D. Albesa-Jove, A. S. Batsanov, J. A. K. Howard, H. M. Kaiser, D. E. Kaufmann, S.-K. Poon, W.-Y. Wong, C. Jardin, S. Fathallah, A. Boucekkine, J.-F. Halet, T. B. Marder. Chem. Eur. J. 2006, 12, 2758. [3] J. S. Siddle, R. M. Ward, J. C. Collings, S. R. Rutter, L. Porrès, L. Applegarth, A. Beeby, A. S. Batsanov, A. L. Thompson, J. A. K. Howard, A. Boucekkine, K. Costuas, J.-F. Halet, T. B. Marder. New J. Chem. 2007, 31, 841. [4] C. D. Entwistle, J. C. Collings, A. Steffen, L.-O. Pålsson, A. Beeby, D. Albesa-Jové, J. M. Burke, A. S. Batsanov, J. A. K. Howard, J. A. Mosely, S.-Y.Poon, W.-Y. Wong, F. Ibersiene, S. Fathallah, A. Boucekkine, J.-F. Halet, T. B. Marder. J. Mater. Chem. 2009, 19, 7532.

[5] A. Steffen, K. Costuas, A. Boucekkine, M.-H. Thibault, A. Beeby, A. S. Batsanov, A. Charaf-Eddin, D. Jacquemin, J.-F. Halet, T. B. Marder. Inorg. Chem. 2014, 53, 7055.

[6] L. Ji, R. M. Edkins, L. J. Sewell, A. Beeby, A. S. Batsanov, K. Fucke, M. Drafz, J. A. K. Howard, O. Moutounet, F. Ibersiene, A. Boucekkine, E. Furet, Z. Liu, J.-F. Halet, C. Katan, T. B. Marder. Chem. Eur. J. 2014, 20, 13618. [7] C. Sieck, M. G. Tay, M.-H. Thibault, K. Costuas, J.-F. Halet, A. S. Batsanov, M. Hähnel, A. Steffen, T. B. Marder. Submitted.

mailto:[email protected]



8 Invited Lectures

Ashok KAKKAR Department of Chemistry McGill University 801 Sherbrooke St. West, Montreal, Quebec H3A 0B8, CANADA E-mail: [email protected] Designing Adaptive Nanostructures for Multi-Tasking in Nanomedicine

Considering the complexities of modern nanomedicine, challenges in therapeutics and theranostics have provoked the design of efficient nanocarriers that combine multiple functions into a single platform. For any therapeutic intervention, efficient delivery, targeting, tracking the fate and final outcome are essential parameters that need to be controlled. Chemists have taken this enormous task to develop versatile tools which can allow the design of tailor-made nanocarriers that can combine multiple complementary functions into the same scaffold of a nanostructure. We have recently developed facile synthetic methodologies in which orthogonally functionalized building blocks can be utilized to assemble a multivalent structure with desired spatial distribution of therapeutic, imaging and targeting capabilities. We shall elaborate on this macromolecule-based nanotechnology, and discuss its potential in smart and efficient drug therapy. We shall demonstrate how one can easily construct multivalent nanoconjugates which can perform multiple tasks and help visualize drug delivery.



Invited Lectures 9

Christian KLEEBERG Institut für Anorganische und Analytische Chemie Technische Universität Braunschweig Hagenring 30, 38106 Braunschweig, GERMANY E-mail: [email protected] Boron-Element Compounds: From CuI Catalysis to Boryl Complexes

Boron-element compounds containing a B–E bond (E: group 14 element or boron) of the type (RO)2B–ER3 and (RO)2B–BX2 are widely making use of the unique reactivity of B–E bonds. Whilst these types of compounds are especially well established as reagents in transition metal catalysed reactions, they are also versatile precursors for the synthesis of transition metal triorgano-group 14 element or boryl complexes. Those complexes are relevant as reactive intermediates in catalytic processes, e.g. borylation or silylation reactions, but are also of interest in their own right due to their unique (coordination) chemical properties.[1]

Different aspects of the reactivity of boron-element compounds will be addressed, ranging from NHC-CuI-complexes as (model) catalysts in CuI catalysed silylation reactions with silylboranes, to the use of unsymmetrical diborane(4) derivatives as versatile sources for diaminoboryl ligands.[2,3]

References: [1] For selected reviews, see: (a) M. Oestreich et al. Chem. Rev. 2013, 113, 402. (b) H. Braunschweig. Angew. Chem. Int. Ed. 1998, 37, 1786. (c) I. A. I. Mkhalid et al. Chem. Rev. 2009, 110, 890. [2] (a) J. Plotzitzka, C. Kleeberg. Organometallics 2014, 33, 6915. (b) C. Kleeberg, E. Feldmann, E. Hartmann, D. J. Vyas, M. Oestreich. Chem. Eur. J. 2011, 17, 13538. (c) C. Kleeberg, M. S. Cheung, Z. Lin, T. B. Marder. J. Am. Chem. Soc. 2011, 133, 19060. [3] (a) C. Borner, C. Kleeberg. Eur. J. Inorg. Chem. 2014, 2486. (b) C. Borner, K. Brandhorst, C. Kleeberg. Dalton Trans. 2015, 44, 8600.



10 Invited Lectures

Ruming YUAN and Zhenyang LIN Department of Chemistry Hong Kong University of Science and Technology Clear Water Bay, Kowloon, HONG KONG E-mail: [email protected] Computational Insight into Mechanism of Nickel-Catalyzed Reductive Carboxylation of Styrenes Using CO2

The detailed mechanisms for the reductive carboxylation of styrenes using CO2 catalyzed by nickel complexes have been studied with the aid of DFT calculations. Two possible mechanisms, the oxidative-coupling mechanism and the nickel-hydride mechanism, were calculated and compared. In this talk, we will report the calculation results and discuss how the competitive nature between the two mechanisms affects the reaction outcome as a result of different reaction conditions (such as pressure) and different substrates and different ligands.

References: [1] C. M. Williams, J. B. Johnson, T. Rovis. J. Am. Chem. Soc. 2008, 130, 14936. [2] R. Yuan, Z. Lin. Organometallics 2014, 33, 7147.



Invited Lectures 11

Paul LOW School of Chemistry and Biochemistry University of Western Australia 35 Stirling Highway, Crawley, Perth, AUSTRALIA 6009 E-mail: [email protected] Building Bridges: New Aspects of the Chemistry and Spectroscopic Properties of 'Mixed-Valence' Complexes

Intramolecular electron transfer processes are perhaps the most fundamental of chemical processes, involving no more than the migration of an electron within the molecular framework. Nature has evolved remarkable systems to move precisely, and use, electrons through electron transfer cascades to power the processes essential to life. To help unravel these processes, model complexes of the type [{E}-bridge-{E}]+ have been exploited, and the seminal works of Marcus, Taube and Hush have led to well-established ‘two-state’ models based on the mixing of states describing the localisation of charge on the ‘left’ (reactant) or ‘right’ (product) electrophore, {E}. Through classical analysis, these systems allow extraction of various electronic terms from experimentally measurable spectroscopic parameters. Since the original expression of these ideas, many more sophisticated models have been developed, which include descriptions of vibronic coupling and the introduction of multiple states allowing explicit treatment of the bridge within the electron-transfer process. However, all of these models have been based on a treatment of the molecular framework in a single lowest energy conformation. In this presentation, we will describe the role that multiple, thermally accessible molecular conformations lying close in energy can have on the spectroscopic and electronic properties of such ‘mixed-valence’ systems. These results raise some questions about what we mean when we describe a fluxional molecular system in terms of the limiting descriptions of ‘localised’ or ‘delocalised’ electronic structures, and some concepts for the analysis of such systems based on DFT methods will be discussed.



12 Invited Lectures

Seth R. MARDER,a Junxiang ZHANG,a Anthony ROJAS,a Timothy PARKER,a Simon BLAKEYb and Jennifer BONb a School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, U.S.A. b Department of Chemistry, Emory University, Atlanta, GA, U.S.A. E-mail: [email protected] Advances, Challenges and Opportunities for Direct C-H Bond Functionalization in Materials Chemistry

Organic moieties with high electron affinities (EAs) may act as intra- and intermolecular acceptors in -conjugated materials for applications in non-linear optics, organic light emitting diodes, organic photovoltaic material systems,

and organic field-effect transistors. However, incorporation of strong -acceptors into either small molecule or polymer materials can be problematic since many high-EA precursors are resistant to electrophilic halogenation and lithiated derivatives that are typically used to form Stille and Suzuki reagents, which are often unstable. Direct

C-H bond functionalization on sp2 carbon centers has become a useful tool for the synthesis of -conjugated small molecules and polymers. Direct C-H arylation can be particularly useful in the synthesis of materials with high EA, where it may be used to circumvent some of the synthetic difficulties associated with strongly electron-accepting intermediates and with conventional cross-coupling partners. To explore the scope of direct C-H arylation of high EA materials, we have synthesized several heterocycles based on widely used 2,1,3-benzothiadiazole (BT), benzotriazole (BTz), and quinoxaline (Qx) acceptors with pendant electron withdrawing substituents to increase EA relative to the parent acceptors. Palladium-catalyzed direct heteroarylation of 5,6-dicyano[2,1,3]benzo-thiadiazole (DCBT), 5,6-dicyano[1,2,3]benztriazole (DCBTz), 6,7-dicyanoquinoxaline (DCQx), and 6,7-dinitro-quinoxaline (DNQx) was accomplished with high yields (>80%) of di-coupled products in most cases. Electron acceptor and transport materials for organic photovoltaics and transistors synthesized by these direct C-H arylation methods will be discussed.



Invited Lectures 13

Edward ROBINS Head of Radiochemistry, Singapore Bioimaging Consortium (SBIC), 11 Biopolis Way, #02-02 Helios, SINGAPORE 138667 Head of Preclinical Radiochemistry, Clinical Imaging Research Centre (CIRC), Yong Loo Lin School of Medicine, Centre for Translational Medicine (MD6), National University of Singapore, 14 Medical Drive #B1-01, SINGAPORE 117599. E-mail: [email protected] Palladium-Mediated Organometallic Chemistry of [18F]Fluorinated Intermediates for the Preparation of Radiolabeled Imaging Probes for Positron Emission Tomography (PET)

Clinical and pre-clinical imaging techniques, such as Positron Emission Tomography (PET), have the ability to visualize and monitor molecular events in vivo, providing a functional “picture” of fundamental biochemical and physiological processes.[1,2] The preparation of PET radiopharmaceuticals/tracers relies on the ability of chemists/radiochemists to rapidly and specifically incorporate cyclotron-produced, short-lived positron-emitting (β+ decay) radionuclides, such as 18F (t1/2 = 109.7 min) and 11C (t1/2 = 20.4 min), into drug-like molecules. PET radiochemistry is a challenging, multi-disciplinary field that frequently requires innovative synthetic solutions to prepare evermore structurally complex radiopharmaceuticals. Palladium-catalyzed cross-coupling reactions now play a significant role in the field of organic synthesis and have made possible the synthesis of many complex molecules and molecular architectures. Despite the significant impact of palladium-catalyzed cross-coupling reactions, as well as many other metal-mediated reactions, the application of organometallics and metal-mediated chemistry in the preparation of PET radiopharmaceuticals has been more limited, although is now becoming more prevalent.[3] Recently, we have reported the development of the Pd-m-terarylphosphine catalyst system, PdCl2(Cy*Phine)2, which has demonstrated high catalytic efficiency for copper-free Sonogashira,[4] Mizoroki-Heck,[5] and other Pd-mediated cross-coupling chemistries.[6] Herein, this presentation will highlight the design, preparation and the range of chemistries of the Pd-Cy*Phine system, its application to (hetero-)aryl cross-coupling chemistries, and our initial studies on the cross-coupling of radiolabeled fragments for the preparation of PET radiopharmaceuticals.

References: [1] M. E. Phelps. Proc. Nat. Acad. Sci. U.S.A. 2000, 97, 9226. [2] (a) S. M. Ametamey, M. Honer, P. A. Schubiger. Chem. Rev. 2008, 108, 1501. (b) D. W. Townsend. J. Nucl. Med. 2008, 49, 938. [3] For recent examples see: (a) F. Ku ̈gler, J. Ermert, P. Kaufholz, H. H. Coenen. Molecules 2015, 20, 470. (b) X. Huang, W. Liu, H. Ren, R. Neelamegam et al. J. Am. Chem. Soc. 2014, 136, 6842. [4] (a) Y. Yang, X. Chew, C. W. Johannes, E. G. Robins et al. Eur. J. Org. Chem. 2014, 7184. (b) Y. Yang, J. F. Y. Lim, X. Chew, E. G. Robins et al. Catal. Sci. Technol. 2015, 5, 3501. [5] D. W. Tay, H. Jong, Y. H. Lim, W. Wu, X. Chew, E. G. Robins et al. J. Org. Chem. 2015, 80, 4054. [6] E. G. Robins, C. W. Johannes et al. Unpublished results.



14 Invited Lectures

Webster SANTOS Department of Chemistry Virginia Tech 306 Hahn Hall North, Blacksburg, VA 24061, U.S.A. E-mail: [email protected] Copper-Catalyzed Borylation of Alkenes: Towards Sustainable Chemistry

Organoboron compounds are excellent substrates for the Suzuki-Miyaura cross-coupling reaction and play a key role in medicinal compounds and materials science. Therefore, development of methods for their synthesis is important. While many protocols have been disclosed, the majority employ transition metals as catalysts, typically in organic solvents as the reaction medium. A major disadvantage of these methods is the cost and negative environmental impact. Thus, the development of sustainable and environmentally friendly reaction conditions are desirable. In this symposium, we will discuss our effort on the development of a user- and environmentally friendly protocol for the generation of borylated organic compounds. In general, activated alkenes, alkynes, and allenes are converted to the corresponding borylated derivatives using a copper(II) catalyst, base additive, and diboron reagent using water as the reaction medium and open to the atmosphere. The products are isolated in high yields with good to excellent regio- and stereoselectivity. References: [1] S. B. Thorpe, J. A. Calderone, W. L. Santos. Org. Lett. 2012, 14, 1918. [2] J. A. Calderone, W. L. Santos. Org. Lett. 2012, 14, 2090. [3] J. A. Calderone, W. L. Santos. Angew. Chem. Int. Ed. 2014, 53, 4154. [4] G. Xi, A. Nelson, W. L. Santos. ACS Catal. 2015, 5, 2172. [5] C. L. Peck, J. A. Calderone, W. L. Santos. Synthesis 2015, 47, 2242.



Invited Lectures 15

Shigeru SHIMADA Interdisciplinary Research Center for Catalytic Chemistry National Institute of Advanced Industrial Science and Technology (AIST) Tsukuba, Ibaraki 305-8565, JAPAN E-mail: [email protected] Organodibismuthines: Unique Reactivity and Application in Organic Synthesis

The high reactivity of Bi-Bi single bonds makes dibismuthines potentially useful precursors for various bismuth compounds as well as reagents for organic synthesis.[1] However, such applications are very limited so far, partly because of their instability. We have been working on cyclic organobismuth compounds, 5,6,7,12-tetrahydrodibenz- [c,f][1,5]azabismocines 1. The cyclic structure of compounds 1 has high thermal stability. We expected that dibismuthines possessing azabismocine frameworks would have enough stability for the above-mentioned applications. We have found an efficient and unique synthetic procedure for dibismuthines 2.[2] As expected, compounds 2 have high thermal stability, while keeping the high reactivity of the Bi-Bi bond. Here, synthesis, unique reactivity and some application in organic synthesis will be presented. Dibismuthines 2 (R1 = tBu, tOct, Me) can be easily synthesized by the reaction of bismuth hydroxides 3 with 9,10-dihydro-9-oxa-10-phosphaphenan-threne-10-oxide, a commercially available and relatively cheap compound. Compounds 2 are easily transformed to alkylbismuth compounds 1 (R = alkyl) by simply heating a mixture of 2 and alkyl halides. Resulting compounds 1 can be cross-coupled with aryl halides in the presence of Pd catalysts. The two-step reaction shown in Scheme 1 can be performed in a one-pot manner without isolation of compounds 1. This reaction is tolerant to various functional groups including hydroxy and carboxy groups. Further scope of dibismuthine reagents 2 will be discussed.

Scheme 1. One-Pot Cross-Coupling Reaction Using Dibismuthines 2

References: [1] L. Balázs, H. J. Breunig. Coord. Chem. Rev. 2004, 248, 603. [2] S. Shimada, J. Maruyama, Y.-K. Choe, T. Yamashita. Chem. Commun. 2009, 6168.

NR1 Bi R

1

2 R X 1 R Ar

[Bi] X

[Bi] Br+ +

Ar Br+

Pd cat

N R1BiN BiR1

2

[Bi] N R1Bi=

R = Alkyl, X = Cl, Br, I

NR1 Bi OH

3



16 Invited Lectures

Patrick STEEL Department of Chemistry University of Durham, Durham DH1 3LE, U.K. E-mail: [email protected] Enhancing the Borylation Experience: Extending and Applying Ir-Catalysed C-H Borylation

Organoboronic acids and esters are a class of compounds of great importance in organic synthesis and material science with a growing role in medicinal chemistry/chemical biology. They represent ideal reagents, being non-toxic, tolerant to air and water, stable in the absence of a catalyst, and react under mild conditions in a diverse range of transformations. Traditionally, boronic acids are generated via the reaction of air and moisture sensitive organolithium or Grignard reagents with a trialkylborate followed by hydrolysis or transesterification. However, this restricts the scope of the reaction to substrates free of reactive functional groups, or adds costly protection/deprotection steps. Whilst milder methods involving the reaction of alkoxyborane reagents with arylhalides have been developed, these rely on prefunctionalised substrates. Over the last decade, the direct C-H borylation of aromatic C-H bonds catalysed by tris-boryl-iridium complexes has become the method for the synthesis of aromatic boronic acids. Whilst there are many commercially available boronic acids (>7,000 on SciFinder), these are mainly benzenoid, and access to heterocyclic analogues, of greater relevance to the pharmaceutical and agrochemical industries, is challenging. This presentation will describe strategies based on the iridium-catalysed C-H borylation of aromatic C-H bonds that enable the synthesis of otherwise difficult to access azinyl boronate esters, together with applications in ‘one-pot’ transformations that offer greater synthetic efficiency.



Invited Lectures 17

Kálmán J. SZABÓ Department of Organic Chemistry, Arrhenius Laboratory Stockholm University, SE-106 91 Stockholm, SWEDEN E-mail: [email protected] Web: http://www.organ.su.se/ks/ Transition Metal Catalyzed C-H Borylation of Alkenes

Catalytic C-H borylation has become a useful synthetic tool in organic chemistry. Although most efforts are concentrated on synthesis of arylboronates by transition metal catalysis, borylation of alkenes also received considerable attention. For alkenes, both the sp2 (vinylic) and the sp3 (allylic) C-H bonds can be selectively borylated. Our studies have shown that, by Ir-catalyzed reactions, both the vinylic and allylic C-H bonds of the cyclic alkenes can be borylated (eq. 1).[1] In the case of acyclic alkenes, only the vinylic boronates can be obtained.

Subsequent studies have shown that, under strongly oxidative conditions, palladium catalysis can also be suitable for vinylic C-H borylation of alkenes (eq. 2). In these processes, the reactions can be conducted under mild conditions at room tempretaure.[2]

Recently, we have found[3] that the reaction can be conducted via allyl-palladium complexes, which allows formation of allylboronates, even for alkenes without exocyclic double bonds (such as in eq. 1). These reactions can be conducted in the presence of aldehydes. The one-pot borylation–allylboration reaction results in stereodefined homoallyl alcohols from alkenes (eq. 3).

References: [1] (a) V. J. Olsson, K. J. Szabó. Angew. Chem. Int. Ed. Engl. 2007, 46, 6891. (b) V. J. Olsson, K. J. Szabó. Org. Lett. 2008, 10, 3129. [2] N. Selander, B. Willy, K. J. Szabó. Angew. Chem. Int. Ed. 2010, 49, 4051. [3] H.-P. Deng, L. Eriksson, K. J. Szabó. Chem. Comm. 2014, 50, 9207.



18 Invited Lectures

Matthias WAGNER Institut für Anorganische und Analytische Chemie Goethe-Universität Frankfurt am Main Max-von-Laue-Str.7, 60438 Frankfurt am Main, GERMANY E-mail: [email protected] Boron-Doped Graphene Flakes

Polycyclic aromatic hydrocarbons (PAHs) are highly promising optoelectronic materials. Key parameters, such as the electron affinity or the fluorescence wavelength, can be adjusted through the introduction of substituents at the perimeter of the PAH. An even greater effect is created when selected carbon atoms within the PAH scaffold are replaced by other p-block atoms. Our group is particularly interested in boron as the electronically perturbative element. As a rule of thumb, boron doping leads to the lowering of the LUMO energy level of a PAH, thereby providing access to excellent electron acceptors, which also tend to be strongly luminescent in the visible range of the electronic spectrum. The actual preparation of boron-containing PAHs is still a considerable challenge. In the recent past, we have developed synthesis routes based on B−B-coupling reactions, photocyclisation reactions, and the transition-metal mediated late-stage derivatisation of boron heterocycles. This enables us to modify systematically the molecular structure of a given target molecule, which is the prerequisite for an understanding of structure-property relationships.



Invited Lectures 19

Lawrence W.-Y. WONG, Herman H.-Y. SUNG, Gemma S.-S. TAM and Ian D. WILLIAMS Department of Chemistry Hong Kong University of Science and Technology Clear Water Bay, Kowloon, HONG KONG E-mail: [email protected] From Resolving to Use Boron to Resolving with Boron: Spiroborate Anions for Crystallization and Chiral Separation

Spiroborates are a family of anionic boronic esters which are cheap and readily formed in situ for the purpose of crystallization of organic and metal-organic salts. Since a number of chiral spiroborates can also be prepared, they are also versatile resolving agents. In this paper, we explore the main advantages and limitations of their use and give a number of examples of resolution from simple industrial chiral amines to natural alkaloids to metal-organic coordination compounds. One advantage is that the size, shape, chemical functionality and solubility of the spiroborate is readily modified. A general characteristic is that they are semi-rigid, which seems to assist the crystallinity of many of their salts first recognized and explored in the 1990s by Marder et al.[1,2] Chirality may be conferred by use of chiral chelating groups, such as S,S-hydrobenzoinate shown below, or at boron itself from asymmetric chelates, as found for bis(salicylato)borates. The chirality at boron is labile in protic media, but quite stable in aprotic solution. Spiroborate resolutions can be conducted as facile one-pot solvothermal crystallizations, or from metathesis crystallization from useful pre-prepared reagents such as Na[B(S-Man)2], where Man = mandelate.[3]

References: [1] W. Clegg, A. J. Scott, F. J. Lawlor, N. C. Norman, T. B. Marder, C. Y. Dai, P. Nguyen. Acta Cryst C 1998, 54, 1875. [2] W. Clegg, M. R. J. Elsegood, A. J. Scott, T. B. Marder, C. Y. Dai, N. C. Norman, N. L. Pickett, E. G. Robins. Acta Cryst. C 1999, 55, 733. [3] L. W-Y. Wong, W-H. Kan, T. Nguyen, H. H-Y. Sung, D. Li, A. S-F. Au-Yeung, R. Sharma, Z. Lin, I.D. Williams. Chem. Commun. 2015, in press.



20 Invited Lectures

Jingping ZHANG Faculty of Chemistry Northeast Normal University Changchun 130024, CHINA E-mail: [email protected] Mechanistic Understanding Towards Economic Synthesis of Pyrrole Derivatives

DFT investigations are carried out to improve the domino cyclization between gem-dialkylthio vinylallenes and benzylamine (BnNH2) forming pyrroles.[1] Economic reaction approaches were explored, namely, this reaction can occur under organic solvent-free conditions either catalyzed by trace water or self-catalyzed by BnNH2. Three types of reactions (DMSO-assisted, trace water-catalyzed, and self-catalyzed by BnNH2) shared the same reaction mechanism with the nucleophilic attack of BnNH2 on the allenic carbon of the thioamide intermediate. For trace water-catalyzed reaction, another mechanism was also found that is the BnNH2 attacks the carbonyl carbon of the conformational isomer of Re. Among the investigated mechanisms, the trace water-catalyzed one is suggested to be the most efficient and convenient synthetic method for pyrroles. Our calculated results were further confirmed by the experimental observation, which opens a new strategy for the synthesis of pyrroles.

Reference: [1] H. Y. Yuan, Y. Y. Zheng, Z. X. Fang, X. H. Bi, J. P. Zhang. Green Chem. 2014, 16, 26



Invited Lectures 21

Sessions Chairs

Prof. Dr. Maik FINZE

Prof. Dr. Klaus MÜLLER-BUSCHBAUM

Prof. Dr. Udo RADIUS

Prof. Dr. Ulrich SCHATZSCHNEIDER

Invited Posters



Invited Posters 25

Scott COLLINS,a,b Mikko LINNOLAHTI,c J. Scott McINDOE b and Odilia PEREZ a a Centro de Investigación en Química Aplicada, Saltillo, MEXICO b Department of Chemistry, University of Victoria, CANADA c Department of Chemistry, University of Eastern Finland, Joensuu, FINLAND E-mail: [email protected] Modification of Methylaluminoxane as Studied by Electrospray Ionization Mass Spectrometry (ESI MS). Does the Dog Wag the Tail or Vice Versa?

Recent experimental (mainly involving ESI MS)[1] and theoretical work[2] has established that the mechanism of methylaluminoxane (MAO) in metallocene catalyst activation for olefin polymerization is different than that proposed based on studies of higher homologues.[3] Specifically, MAO is a source of the electrophilic [Me2Al]+ moiety,[1a-b,2] and activation of Cp2ZrCl2 may proceed via competitive alkylation, and ionization involving this species.[1c] The by-product of alkylation, Me2AlCl, modifies the neutral components of MAO, as well as the ion-pairs formed in situ, by displacement of bound Me3Al, leading to (poly)chlorination of the anions. This should be contrasted with the behaviour of Cp2ZrMe2, requiring only ionization, and intermediate behaviour of Cp2ZrMe(Cl), where chlorination is far less extensive. The net result is that the ion-pairs (both the cations and anions) formed on activation of Cp2ZrCl2 are changing as a function of the Al:Zr ratio, while with Cp2ZrMe2, the anions formed are invariant to this ratio, though the cations formed are sensitive to it. These studies suggest that the polymerization behaviour of these two catalyst precursors (i.e. Cp2ZrCl2 vs. Cp2ZrMe2) should differ significantly as a function of the Al:Zr ratio, as ion-pairing is known to be important for catalyst activity. Definitive literature studies on this issue are lacking – catalyst activity is strongly dependent on both absolute [Zr] and, to a lesser extent, [Al] concentration during polymerization, at least in the case of Cp2ZrCl2.[4] In this presentation, we will discuss polymerization experiments as well as ESI MS data that allow one to address these issues for MAO-activated systems. References: [1] (a) T. K. Trefz et al. Organometallics 2013, 32, 3149. (b) F. Ghiotto et al. Organometallics 2013, 32, 3354. (c) T. K. Trefz et al. Chem. Eur. J. 2015, 21, 2980. [2] (a) J. T. Hirvi et al. Chem. Phys. Chem. 2014, 15, 2732. (b) M. S. Kuklin et al. Organometallics 2015, 34, 3586. [3] Recent review: H. S. Zijlstra, S. Harder. Eur. J. Inorg. Chem. 2015, 19. [4] B. Rieger, C. Janiak. Makromol. Chemie 1994, 215, 35.



26 Invited Posters

Tolulope FASINA and Abimbola OLUWALANA Chemistry Department University of Lagos Akoka, Lagos, NIGERIA E-mail: [email protected] Absorption and Emission Properties of Schiff Bases Derived from Diphenyl Acetylenes

Substituent and solvent effects on the absorption and emission properties of ten Schiff bases derived from 4-amino,4’-(substituted) diphenylacetylenes were studied in five solvents of different polarities. The effects of substituents on the spectra are correlated with the Hammett constants. The solvent effects are interpreted using the linear salvation energy relationship. Results indicate that electron-withdrawing substituents produce hypsochromic shift in the absorption maximum. The compounds are fluorescent in polar solvents, with the fluorescence quenched in non-polar solvents.



Invited Posters 27

Graeme HOGARTH and Shishir GHOSH Department of Chemistry Kings College London Britannia House, 7 Trinity Street, London SE1 1DB, U.K. E-mail: [email protected] Bioinspired Catalysis: Low Valent Iron Clusters as Efficient Electrocatalysts for Clean Hydrogen Production

The large scale production of hydrogen via economically and environmentally sustainable methods is a major societal challenge, and the electrocatalytic reduction of protons by cheap, sustainable and biodegradable catalysts is a pragmatic approach to the issue, as the electrons required can be derived from renewable sources. Nature does this by using hydrogenases which contain low-valent binuclear centres at their core, with the ability to bind protons to both electronegative (nitrogen) and electropositive (iron) atoms, and thus facilitate both hydrogen activation and formation. In this contribution, we describe two of our recent bioinspired efforts at using low-valent iron clusters containing potential hydride and proton binding sites as proton reduction catalysts. The first centres

around the novel oxo butterfly cluster, Fe4(CO)10(4-O)(2-dppn), which catalyses proton reduction at its second reduction potential. However, here, DFT calculations suggest that the oxo ligand plays no direct role as a proton binder.[1] More recently, we have focused on trinuclear clusters with 2-aminopyridinate (X = CH) capping ligands (Figure) in which the pre-catalyst already has pre-bound protic and hydridic hydrogen atoms, and we aimed to activate their catalytic combination electrochemically. Further, use of related pyrimidinate (X = N) potentially provides a synthetic proton-channel to the catalytic centre. We have also investigated their ruthenium analogues in order to gain mechanistic information regarding their modes of action.

Reference: [1] S. Ghosh, K. B. Holt, S. E. Kabir, M. G. Richmond, G. Hogarth. Dalton Trans. 2015, 44, 5160. In the spirit of international collaboration, we thank Professor Mike Richmond (University of North Texas) for DFT calculations, Dr Katherine Holt (UCL) for expert electrochemical advice, and collaborators in this venture Professors Ebbe Nordlander (Lund University) and Shariff Kabir (Jahangirnagar University).



28 Invited Posters

Audrey LEDOUX,a Paolo LARINI,b Christophe BOISSON,a Vincent MONTEIL,a Jean RAYNAUDa* and Emmanuel LACOTEa* a Université Claude Bernard Lyon 1, Institut de Chimie de Lyon–CPE Lyon C2P2, Lyon, FRANCE b Institut de Chimie et Biochimie Moléculaires et Supramoléculaires 43, Bd du 11 Novembre 1918, 69616 Villeurbanne cedex, FRANCE E-mail: [email protected] Polyboramines as Hydrogen Reservoirs

Boron-based polymers have been the focus of growing attention because they exhibit outstanding properties, such as photoluminescence, electroluminescence, nonlinear optical properties, n-type semiconductivity, etc. that make them well-suited as materials for organic electronics, imaging, or ion and molecule sensing.[1,2] Dihydrogen storage and controlled release has become an essential area of research aspiring to answer the ever-growing energetic demand. If ammonia-borane (NH3BH3) was early on identified as a premium candidate to constitute a H2 reservoir, due to its maximum storage capacity (19.6 wt %. H2),[3,4] researchers have then identified its shortcomings such as poor processability and troublesome material recycling.[5,6] We have proposed to address these issues throughout the synthesis of new amine-borane polymers, via a polycondensation methodology, harnessing the reactivity and joint H2-storing capacity of amine and borane moieties. We aimed at an ease of preparation, an enhanced processability and a mapping of structure-property relationship, but also at a straightforward access to recyclable materials via simple re-hydrogenation techniques, offsetting their lower hydrogen storage capacity compared to ammonia-borane. We have synthesized polyboramines from simple protected organic building blocks. H2-storing polymers could be obtained featuring molar masses up to 105 g/mol (Mn). They possess a Tg (~60°C) and are soluble in THF. H2 equivalents are readily available by transfer hydrogenation as well as thermal dehydrogenation. Interestingly, they release H2 thermally with a unique profile, which is a direct consequence of the polymeric nature of the material. Herein we present the first results on a new class of polyboramines as well as computational studies that bring us informations to understand the key role of the polymer backbone on the reactivity.

References: [1] F. Jäkle. Chem. Rev. 2010, 110, 3985. [2] W. Wan, F. Cheng, F. Jäkle. Angew. Chem. Int. Ed. 2014, 53, 8934. [3] a) C. A. Jaska, K. Temple, A. J. Lough, I. Manners. J. Am. Chem. Soc. 2003, 125, 9424.

b) T. B. Marder. Angew. Chem. Int. Ed. 2007, 46, 8116. [4] A. Staubitz, A. P. M. Robertson and I. Manners. Chem. Rev., 2010, 110, 7. [5] Z. Liu and T. B. Marder. Angew. Chem. Int. Ed. 2008, 47, 242. [6] W. Luo, L. N. Zakharov, and S. Y. Liu. J. Am. Chem. Soc., 2011, 133, 13006.



Invited Posters 29

Zhiqiang LIU,a Shiqian ZHANG,a Xiaolan QIAO,b Hongxiang LIb and Qi FANGa a State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, CHINA b Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, CHINA E-mail: [email protected] Functionalize Pyrene at Electrophilic Unfavorable Positions to Build Regioisomeric Thienoacenes as OFET Materials

Pyrene-based materials for organic electronics have been the subjects of tremendous investigation. However, most of pyrene derivatives were synthesized from the direct electrophilic substitution of pyrene itself at the active sites 1, 3, 6, 8-positions. The finding of Marder et al. that Ir-catalyzed direct borylation of pyrene is highly selective for the 2- and 7-positions has opened up a new way to functionalize pyrene. Further work of Marder and us indicated this borylation could also take place at the K-region of pyrene. Recently, we mainly focus on the application of pyrene as a key scaffold of new organic opto-electronic materials. Considering the nature of both extensive intramolecular π-conjugation and strong intermolecular π-stacking of pyrene itself, well-designed pyrene-based thienoacenes should be able to fit the structural requirements of organic semiconductors. Herein, we present the syntheses, crystal structures, and photophysical properties of six isomeric PTAs and related precursors and late-stage oxidized derivatives, which are greatly dependent on the position of substitution on the pyrene skeleton. Up to now, three approaches to the synthesis of new sulfur-bridged multisubstituted pyrene derivative pyrene−thienoacenes (PTAs) were successfully developed. Extensive structural and photoelectronic measurements indicated that cyclization resulted in greatly enhanced intramolecular π-conjugation and intermolecular π-stacking, as well as transistor mobility. Among single-sulfur regioisomeric PTAs, the [3,4]-extended isomer showed much more remarkable properties than [1,2]- and [2,1]- extended isomers. Further primary results indicate that introducing two sulfurs will enhance the OFET properties by at least one order of magnitude. Studies on multi-substituted and multisulfur containing pyrene−thienoacenes are underway in our group.



30 Invited Posters

Yudha Prawira BUDIMAN and Ibraheem A. MKHALID Chemistry Department King Abdulaziz University Jeddah, SAUDI ARABIA E-mail: [email protected] Synthesis and Molecular Structures of Palladium(II) Complexes Containing Monodentate Phenylpyridine Derivatives and their Activity in Suzuki Reaction

Pd-catalyzed cross-coupling is believed to be one of the most important reactions in organic synthesis. Among the many types of C-C cross-coupling reactions, the Suzuki-Miyaura coupling is the most widely used due to the high catalytic efficiency, easily available starting materials, and low toxicity. Pyridine heterocyclic compounds are the most widely active compounds in the pharmaceutical field. Substrates containing heterocyclic nitrogen become a challenge in the development of subsequent Suzuki-Miyaura cross-coupling reactions. Nitrogen-based ligands, which have a higher rigidity and stability to air than phosphine and carbene ligands, would be interesting to apply. Preparation of Pd(II) complexes containing phenylpyridine derivatives as the ligands are described. Crystal structures of the catalysts show a square-planar geometry around the Pd atom, with monodentate ligand coordination to Pd, using N donor of pyridine ring. The square-planar palladium complex trans-[Pd(PyMes)2]Cl2 shows a high efficiency for catalyzing Suzuki-Miyaura cross-coupling reactions under aqueous conditions.

References: [1] N. Miyaura Cross-Coupling Reactions, Japan: Hokkaido University (2001). [2] C. A. Fleckenstein, H. Plenio. Green Chem. 2007, 9, 1287. [3] M. Suzuki. Angew. Chem. Int. Ed. 2011, 50, 6722. [4] A. R. Hajipour, F. Rafiee. Appl. Organometal. Chem. 2013, 27, 412. [5] S. Jindabot, K. Teerachanan, P. Thongkam, S. Kiatisevi, T. Khamnaen, P. Phiriyawirut, S. Charoenchaidet, T. Sooksimuang, P. Kongsaeree, P. J. Angtrirutnugul. J. Organomet. Chem. 2014, 750, 35.



Invited Posters 31

Julia K. Schuster, Holger BRAUNSCHWEIG Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland, 97074 Würzburg, GERMANY E-mail: [email protected] Beryllium Joins the Game: Synthesis of Novel Linear Beryllium Complexes

The synthesis of neutral linear beryllium complexes with different oxidation states has been achieved. Beryllium bis(diazaborolyl) (1) could be synthesized through the reaction of Yamashita´s lithium diazaborolide[1] and BeCl2.[2] To the best of our knowledge, this compound features the first non-cluster bond between beryllium and boron. In accordance with the established chemistry of beryllium,[3] the bonding is polar covalent in character, as determined by structural and spectroscopic analysis, as well as reactivity studies. Additionally, two different neutral compounds (2, 3) consisting of cyclic (alkyl)(amino)carbenes (CAACs)[4] stabilizing a beryllium atom have been isolated and characterized. These complexes show both, linear CAAC–Be–CAAC geometries and very short bond lengths between the central beryllium and the carbenes, which indicates the alignment of the nominally empty p-orbitals on the carbene-carbon of the CAAC ligand with one of the perpendicularly oriented p-orbitals on the beryllium center. Computational investigation of the electronic structure of these compounds indicates significant π-bonding between Be and CAAC, which would feature the first of its kind and confirms the element´s similarities to the remainder of the first full row (2s) of the Periodic Table.

References: [1] Y. Segawa, M. Yamashita, K. Nozaki. Science 2006, 314, 113. [2] T. Arnold, H. Braunschweig, W. C. Ewing, T. Kramer, J. Mies, J. K. Schuster. Chem. Commun. 2015, 51, 737. [3] V. Protchenko, K. H. Birjkumarm, D. Dange, A. D. Schwartz, D. Vidovic, C. Jones, N. Kaltsoyannis, P. Mountford, S. Aldridge. J. Am. Chem. Soc. 2012, 134, 6500. [4] V. Lavallo, Y. Canac, C. Präsang, B. Donnadieu, G. Bertrand. Angew. Chem. Int. Ed. 2005, 44, 5705.



32 Invited Posters

Marco STANOPPIa,b,1 and Andreas STEFFENb a Fachbereich Chemie, Universität Konstanz Fach 711, 78457 Konstanz, GERMANY b Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, GERMANY E-mail: [email protected] First Forays into the Investigation of Cu(I) Complexes as Sensitizers in Photocatalysis

Luminescent molecules, which show thermally activated delayed fluorescence (TADF), have proven to be suitable materials for light emitting devices and other photonics applications.[1] One requirement for this phenomenon to occur is a sufficiently small energy gap between the first triplet excited state T1 and the first singlet excited state S1

(EST). Molecules in the T1 excited state can then undergo an “up intersystem crossing” to S1, which can then radiatively relax to the S0 ground state. In the case of copper(I) complexes, little is known about the simple structural features that can enhance or inhibit TADF.[2] Therefore, a series of benzimidazole and benzothiazole based copper complex have been synthesized to investigate possible trends between structural features and the TADF effect.[3] The energy stored in an excited stated can be converted into light energy, but it can also be transferred to other species. In this case, luminescent molecules do not play the role of emitters but the one of sensitizers. Excited molecules display different properties, such as different oxidation/reduction potentials and diradical character, compared to their singlet ground state. Therefore, switching between the excited states and the ground state of the catalytic species makes control possible over the respective steps (i.e. oxidative addition, reductive elimination) during the catalytic cycle. Some of the benzimidazole based complexes have been used as a starting point to synthesize homo and hetero bimetallic systems in which a subunit is able to harvest the light, and then excite the subunit responsible for the catalysis.[4]

References: [1] A. Yersin. International Patent, 2010, WO2010/006681 A1. [2] M. J. Leitl et al. J. Am. Chem. Soc. 2014, 136, 16032. [3] M. Stanoppi, C. Lenczyk, K. Edkins, A. Lorbach, A. Steffen. (manuscript in preparation). [4] M. Stanoppi, M. Hähnel, A. Steffen. (manuscript in preparation).

1 Marco Stanoppi is a former member of the Research Group of Dr. Andreas STEFFEN, Habilitant candidate and senior researcher in Prof. Dr. Todd B. Marder's Research Group.



Invited Posters 33

Marie-Hélène THIBAULT,a,c Claude PELLETIER,a Josée BOUDREAU,a Mathieu FERRON,a Jacques GAGNON,a Guangling JIAO,a,b Junzeng ZHANG,b Balaji SUBRAMANIAN,c Yahia DJAOUEDc* and Nadia TCHOUKANOVAa* a Coastal Zones Research Institute Inc., 232B, Avenue de l’Église, Shippagan, New Brunswick E8S 1J2, CANADA b Natural Health Product Program, Aquatic and Crop Resource Development, National Research Council Canada, 1411 Oxford Street, Halifax, Nova Scotia B3H 3Z1, CANADA c Research Laboratory in Materials and Raman and FITR Micro-spectroscopy, Université de Moncton-Campus de Shippagan, 218, Boul. J.-D. Gauthier, Shippagan, New Brunswick E8S 1P6, CANADA E-mail: [email protected] Characterization of a New Shrimp Oil from Pandalus Borealis Produced in New Brunswick, Canada

Shrimp oil produced in the Acadian Peninsula, New-Brunswick, is a new product coming from the industrial transformation of shrimp (Pandalus borealis). While shrimps are harvested and transformed for human consumption, their by-products are further processed to extract the oil in a sustainable way. Being a new product, the chemical profiles of this shrimp oil have been studied using an array of analytical methods, ranging from HPLC-DAD/HRMS to NMR and Raman spectroscopies. Shrimp oil harbours a dark red colour due to the presence of astaxanthin, and its characteristics will be presented. Total fatty acids profile (TFAP) and lipid class analyses were performed. Triglycerides with good levels of omega-3 and -6 fatty acids were established as the shrimp oil’s main components. Other notable ingredients will be presented. In conclusion, the shrimp oil produced in New Brunswick Canada presents many qualities entitling it as a prospective functional ingredient for natural health products. Funding sources: Atlantic Innovation Fund, Atlantic Canada Opportunity Agency, New Brunswick Innovation Foundation, National Research Council of Canada’s NHP Program, Natural Sciences and Engineering Research Council of Canada.



34 Invited Posters

Ulrike WAIS,a Haifei ZHANGa and He TAOb a Chemistry Department, University of Liverpool Crown Street, Liverpool L69 7ZD, U.K. b Institute of Chemical and Engineering Sciences 1 Pesek Road, Jurong Island, SINGAPORE 627833 E-mail: [email protected] Nanoformulation of Poorly Water-Soluble Drugs with the Aid of Branched Polymers

Low bioavailability of new developed drugs is a major challenge the pharmaceutical industry is facing today. As organic drug molecules increase in molecular weight, their solubility in aqueous medium decreases and, as such, the ability to reach the target side via oral administration. Making drugs more soluble and readily available for oral administration, thus increasing patient comfort, is a large area of pharmaceutical research. A well-established solution for this is the downsizing of particles to the nanometre range. This technique has the advantages that the drug is changed physically and not chemically, as is done in the formation of prodrugs, hence possible toxic by-products and decomposition products are avoided. In nanodrugs, increased solubility is a direct consequence of size reduction and subsequent higher surface area. Common commercially applied techniques are top-down methods (downsizing by mechanical means) or bottom-up techniques (growth from solution). These techniques require the use of stabilizers, as well as potentially toxic solvents and high energy during production. In our research, we used a novel method of emulsion-freeze-drying to form drug nanoparticles, whereby an emulsion is formed and frozen in liquid nitrogen. Removal of solvents leads to the formation of droplet templated polymer scaffolds with incorporated drug nanoparticles, which dissolve by re-dissolution in water to form stable drug nanosuspensions. Thus, the storage stability is enhanced while the freeze drying process leads to an increase in porosity and as such increased wettability and dissolution. Our partners in Singapore synthesised a temperature sensitive super lightly crosslinked branched copolymer which acts as a surfactant as well as a polymer. Hence, it was possible to form drug nanoparticles of Indomethacin, Ketoprofen and Ibuprofen repeatedly, and independently of oil to water ratio in the ranges of 400 to 200 nm respectively, using only the polymer. It was furthermore possible to form nanoparticles by solvent evaporation from ethanol via a mild, non-toxic and cost effective method.



Invited Posters 35

Kittiya WONGKHAN and Rukkiat JITCHATI (RJ&KW Group) Organometallic and Catalytic Center Department of Chemistry, Faculty of Science Ubon Ratchathani University 85 Sathonlamark Road, Warinchamrap Ubon Ratchathani, 34190 THAILAND E-mail: [email protected] Highly Efficient Blue LECs Using Charged Iridium Complexes

Two heteroleptic charged iridium(III) species comprising two cyclometallating ligands and a neutral diimine ligand

were synthesized and characterized namely {(3,4,7,8-tetramethyl-1,10-phenanthroline-N-N)-bis-(2-(2,4-

difluorophenyl)-5-(trifluoromethyl)pyridine-C6,N)-iridium(III)} hexafluorophosphate (UM01) and {(3,4,7,8-

tetramethyl-1,10-phenanthroline-N-N)-bis-(2-(2,4-difluoro-phenyl)-1H-pyrazole-C6,N)-iridium(III)} hexafluoro-phosphate (UM02), see the structure in Figure 1. Both complexes were used as the blue emitter in OLED and LEC devices. We found that the optimize structure is ITO/PEDOT:PSS/complex:BMIMPF6(1:1)/Al. UM01 gave a current efficiency of 1.14 cdA−1. UM02 shows a blueish CIE coordination at the 0.19, 0.40.

Figure 1. The molecular structure of UM01 and UM02

Reference: [1] U. Mahanitipong, M. Srikaew, Y. Tantirungrotechai, S. Sahosithiwat, K. Wongkhan, R. Jitchati. Acta Physica

Polonica A 2015, 127, 1109.



36 Invited Posters

Dongxia ZHU Faculty of Chemistry Northeast Normal University Changchun 130024, CHINA E-mail: [email protected] New AIE-Active Dinuclear Ir(III) Complexes with Reversible Piezochromic Phosphorescence Behaviour

Phosphorescent transition metal complexes are widely exploited in various optoelectronic applications due to their rich excited-state properties, such as high luminescence quantum yields, long emission lifetimes, large Stokes shifts and high photo-stability compared to fluorescent dyes.[1] Piezochromic materials, the emissions of which can be repeatedly switched between different colours under external pressure or mechanical grinding, have received considerable attention in the construction of optical data recording and storage devices.[2] Aggregation-induced emission (AIE) in the solid or aggregated state, which is the opposite of ACQ, was first reported by Tang et al. in 2001.[3] The development of a new class of Schiff base piezochromic materials with AIE-activity is of fundamental importance in exploring the relationship between solid state structure and luminescence.

Inspired by this idea, herein, we describe two new dinuclear cationic Ir(III) complexes, [(2F-ppz)2Ir-(L1)-Ir(2F-ppz)2] [PF6]2 (1) and [(2F-ppz)2Ir-(L2)-Ir(2F-ppz)2] [PF6]2 (2) with Schiff base bridging ligands (L1) and (L2), respectively (Scheme 1). The results obtained demonstrate that both complexes 1 and 2 are AIE-active and simultaneously show piezochromism and vapochromic phosphorescence. We conclude that the flexible bridging ligands play a significant role in achieving these combined properties. Most importantly, the highly reversible piezochromic behaviour makes both complexes competitive candidates for practical applications. Indeed, we have shown that complex 2 provides a fast-responding re-writable phosphorescence data recording device.

Scheme 1. Chemical structure of the complexes 1 and 2, with a phosphorescence re-writable data recording device based on complex 2.

References: [1] M. A. Baldo, D. F. O’Brien, Y. You, A. Shoustikov, S. Sibley, M. E. Thompson, S. R. Forrest. Nature 1998, 395, 151. [2] M. Burnworth, L. Tang, J. R. Kumpfer, A. J. Duncan, F. L. Beyer, G. L. Fiore, S. J. Rowan, C. Weder. Nature 2011, 472, 334. [3] J. Luo, Z. Xie, J. W. Lam, L. Cheng, H. Chen, C. Qiu, H. S. Kwok, X. Zhan, Y. Liu, D. Zhu, B. Z. Tang. Chem. Commun. 2001, 1740.



Invited Posters 37

Xunjin ZHU, Song CHEN and Wai-Kwok WONG Institute of Molecular Functional Materials Department of Chemistry and Institute of Advanced Materials Hong Kong Baptist University Waterloo Road, Kowloon Tong, HONG KONG E-mail: [email protected]. Design and Synthesis of New Porphyrin-Centered Small Molecules for Photovoltaic Applications

Solution processed bulk heterojunction (BHJ) organic solar cells (OSCs) are considered one of the most promising alternatives to inorganic solar cells, because of their low cost, light weight, and flexibility.[1] Specifically, small molecule BHJ OSC have attracted much more attention recently, in which small molecule as donor material have defined molecular structures and molecular weights, high purity, and less batch-to-batch variations in comparison with their polymer counterparts.[2] Inspired by natural photosynthetic systems, which utilize chlorophylls to absorb light and carry out photochemical charge separation to store light energy, we herein designed and synthesized a series of new acceptor-donor-acceptor (A-D-A) type porphyrin-centered small molecules for photovoltaic applications. From the fact that the conventional 3,5-alkyl substituted phenyl ring protruded out of the porphyrin plane, it has been adopted to improve the solubility and suppress aggregation. However, the suppressed intermolecular π–π stacking results in low charge mobility and consequently a relatively poor photovoltaic performance.[3] In these studies, replacing the phenyl ring with direct alkyl chains in different patterns can effectively decrease the tendency of crystallization and enhance the solubility as well as intermolecular π–π stacking, leading to a new class of porphyrin-centered small molecules with high charge mobility. Using PC71BM as acceptor and those new porphyrin-based molecules as donor materials, the highest power conversion efficiency of 7.8% is achieved in the solution-processed bulk-heterojunction solar cells. References: [1] G. Li, R. Zhu, Y. Yang. Nat. Photonics 2012, 6, 153. [2] B. Kan, Q. Zhang, M. M. Li, X. J. Wan, W. Ni, G. K

new this symposium marks the 60th birthday professor dr. todd b. … · 2015. 11. 12. ·...

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