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AromaticandHeterocyclicChemistry
65
Hetroaromatics
Pyridine
properties–pyridineispolarisedbythepresence
ofthenitrogenatom
both
throughthep-system
ands-
framework
thelonepaironnitrogenisorthogonalto
thep-system,andistheHOMOofpyridine;theLU
MOofpyridineisan
anti-bondingp-orbital
pyridineiselectronpoorandundergoesEARSonlyvery
slowly
synthesisofpyridinesandderivatives–generallyaim
tomake
dihydropyridineandthenoxidiseitto
the
correspondingpyridine
dihydropyridinesare
readilypreparedbythecondensationofammoniawith1,5-dicarbonylcompounds
1,5-dicarbonylcompoundsare
readilypreparedbyadditionofanaldehydeorketoneto
ana,b-unsaturated
carbonylcompound
N
![Page 2: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/2.jpg)
AromaticandHeterocyclicChemistry
66
Heteroaromatics
Hantzschpyridinesynthesis
Me
NH2
OMe
O
Ph
CO2Me
OH
Me
r.d.s
otheroxidantsto
convertdihydropyridinesto
pyridinesinclude:(NH4) 2Ce(NO3) 6(CAN),MnO2,DDQ
![Page 3: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/3.jpg)
AromaticandHeterocyclicChemistry
67
Heteroaromatics
Pyridinesynthesiswithhydroxylamine–nooxidantrequired
Electrophilicsubstitutionwithpyridines
E
N
E
![Page 4: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/4.jpg)
AromaticandHeterocyclicChemistry
68
Heteroaromatics
Nitrationofpyridine
nitrationofpyridinewithN2O5
plausiblemechanism
N
NO2NO3
NO
O
NSO3H
NO2
[2,3]-sigmatropic
rearrangement
H
![Page 5: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/5.jpg)
AromaticandHeterocyclicChemistry
69
Heteroaromatics
PyridineN-oxides–much
more
susceptibleto
electrophilicattack
at2and4positions(andto
nucleophilic
additionat2and4positions)
nitrationofpyridineN-oxide
N O
N O
promotesE+addition
at2and4positions
![Page 6: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/6.jpg)
AromaticandHeterocyclicChemistry
70
Heteroaromatics
pyridineN-oxides–N-deoxygenationwithrearrangement
pyridineN-oxides–conversionto
chloro
compounds
N
Me
H
O
Me
O
Cl
![Page 7: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/7.jpg)
AromaticandHeterocyclicChemistry
71
Heteroaromatics
pyridones
nitration
POCl 3
NO
NO2
PCl
OCl
H
![Page 8: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/8.jpg)
AromaticandHeterocyclicChemistry
72
Heteroaromatics
pyridines–nucleophilicsubstitution
Chichibabinreaction
![Page 9: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/9.jpg)
AromaticandHeterocyclicChemistry
73
Heteroaromatics
quinolinesandisoquinolines
Synthesis–Skraupsynthesis
HO
OH
OH2
NOH
H
tautomerise
+H
NOH2
H
![Page 10: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/10.jpg)
AromaticandHeterocyclicChemistry
74
Heteroaromatics
synthesisofisoquinolines
Bischler-Napieralski
POCl 3 N
Cl
R
H
Pictet-Spengler
quinolineandisoquinolineundergoEArS
more
readilythanpyridine,withreactionoccurringonthebenzenoidring
![Page 11: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/11.jpg)
AromaticandHeterocyclicChemistry
75
orderofaromaticity
is:thiophene>pyrrole>furan(enoletherlike)
sulfuristhelargestatom
andhence
isbettermatchedforbondingto
sp2-hybridisedcarbonatomsina5-m
embered
ringleadingto
thiophenebeingthemostaromatic
Heteroaromatics
Pyrrole,ThiopheneandFuran
allthreehave
aromaticproperties
!
"#$
%&"%
$'#
"(&
#")
*!
#"*
+"(&
#,"
-*!
#".
$ /
)',"
'".
$/$
--#
-"(*
"(&
#".
0*/1
($
-'$
!2
".$
/("*
+"(&
#"3
0'4'(
#5
"
thearomaticheterocyclesare
electronrich
Reactions
electrophilicsubstitution–kineticreactionatthe2-positionisfavouredoverreactionatthe3-position
more
reactivethanbenzene–e.g.pyrrolesimilarreactivityto
aniline
![Page 12: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/12.jpg)
AromaticandHeterocyclicChemistry
76
Heteroaromatics
electrophilicsubstitutionofpyrrole,thiopheneandfuran
substituentsalreadypresentonthearomaticheterocycleexertlessdirectingeffectthanthecorresponding
substituentsinbenzene
nitration
![Page 13: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/13.jpg)
AromaticandHeterocyclicChemistry
77
Heteroaromatics
acylationandform
ylation
directedlithiation
![Page 14: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/14.jpg)
AromaticandHeterocyclicChemistry
78
Heteroaromatics
lithium
halogenexchange
metallationofpyrrole
N-m
etallatedpyrrolescanreacteitheratnitrogenorcarbon
generally,themore
ionicthemetal-nitrogenbondthemore
N-alkylationproductsare
form
ed
thiophene
![Page 15: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/15.jpg)
AromaticandHeterocyclicChemistry
79
Heteroaromatics
indole
more
enamine-likethanpyrrole
attack
ofelectrophilesatthebpositionisthelowestenergypathway
iftheb-positionisblockeda-attack
occurs
a-attack
canoccurviab-attack
followedbyrearrangement
N H
2
3
1
attack
atbpositionretains
aromaticsextetofbenzenoid
ring
![Page 16: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/16.jpg)
AromaticandHeterocyclicChemistry
80
Heteroaromatics
Synthesis
pyrrole-synthesisfrom1,4-dicarbonyls,Paal-Knorrsynthesis
froma-aminoketonesandcarbonylcompoundswithactivateda-m
ethylenegroups–Knorrsynthesis
![Page 17: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/17.jpg)
AromaticandHeterocyclicChemistry
81
Heteroaromatics
Hantzschpyrrolesynthesis–froma-chloroketonesandcarbonylcompounds
Furans–Paal-Knorrsynthesis
6
7/$
!'"
8+/
*5
"90&
$-*
%$/1
*!
4-'
$!
2"$
%( :
#"5
#(&
4-#
!#
%*5
.*
7!
2'
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AromaticandHeterocyclicChemistry
82
Heteroaromatics
thiophenes–from1,4-dicarbonylcompounds
from1,2-dicarbonylcompounds–Hinsberg
synthesis
from1,3-dicarbonylcompounds
![Page 19: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/19.jpg)
AromaticandHeterocyclicChemistry
83
Heteroaromatics
Indoles–theFischerindolesynthesis
H N
Ph
NH2
[3,3]-sigmatropic
rearrangement
unsymmetricalketonesgivemixturesofindoles:strongacidsfavourindoleform
ationfromtheless
substituted
ene-hydrazine;weakacidsfavourindoleform
ationfromthemore
substitutedene-hydrazine
![Page 20: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/20.jpg)
AromaticandHeterocyclicChemistry
84
H
HOEt
MeO
protonationatsite
ofhighestcharge
andlargestHOMOcoefficient
H
ReductionofAromatics
Birch
reduction–coveredwithDrSmith
SET
addelectron
•
•MeO
MeO
•
MeO
protonationatsite
ofhighestcharge
togivemoststableradical
protonationatsite
ofhighestcharge
andlargestHOMOcoefficient
CO2
H
HEtO
H
protonationatsite
ofhighestcharge
andlargestHOMOcoefficient
![Page 21: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/21.jpg)
AromaticandHeterocyclicChemistry
85
"H"
further
reduction
ReductionofAromatics
Birch
reductionexamples
Birch
reductionwithC-X
bondcleavage
"H"
naphthalene
![Page 22: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/22.jpg)
AromaticandHeterocyclicChemistry
86
ReductionofAromatics
Birch
reduction–heteroaromatics
pyridine-intheabsence
ofaddedalcoholdim
erisationoftheinterm
ediate
radicalanionoccurs
pyridine-inthepresence
ofaddedalcoholdim
ersare
notform
ed
withsufficientelectronwithdrawinggroups,theadditionofafurtherelectronto
theinitiallyform
edradicalanion
occursto
giveadianion
reactionatmost
basicsite
![Page 23: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/23.jpg)
AromaticandHeterocyclicChemistry
87
ReductionofAromatics
Birch
reduction–pyrroles,furans,thiophenes
electronrich
andhence
requireanelectronwithdrawinggroup
withenoughelectronwithdrawinggroupsfurtherreductionoftheinterm
ediate
radicalanionoccursto
givea
dianion
cf.dianionofalkylacetoacetates
reactswithelectrophilesatmostbasicsite
toleavemoststable,conjugatedenolate
![Page 24: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/24.jpg)
AromaticandHeterocyclicChemistry
88
ReductionofAromatics
Birch
reduction–pyrroles,furans,thiophenes
Hydridereductions–pyridinium
salts
major
minor
![Page 25: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/25.jpg)
AromaticandHeterocyclicChemistry
89
ReductionofAromatics
Hydridereduction–pyridines–bestwithanattachedEWG
Sim
plepyrrolesare
onlyreducedbyhydridereducingagentsinthepresence
ofacid
“Ionichydrogenation”offuranandthiophenegivesthesaturatedderivatives
![Page 26: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/26.jpg)
AromaticandHeterocyclicChemistry
90
ReductionofAromatics
Hydrogenation–complete
reductionofthearomaticring
hydrogenationofaromaticringoccursmostreadilywithPt,RhandRucatalysts;Pdislessactive
alkynes/alkenesandmanyotherfunctionalgroupscanbereadilyreducedinthepresence
ofaromaticrings
Pyridinesare
more
easilyhydrogenatedthanbenzenoidaromatics
hydrogenationofpyrroleandfuranisrelativelystraightforw
ard;hydrogenationofthiopheneiscomplicatedby
catalystpoisoningandthehydrogenolysisoftheC-Sbondwithcomplete
removalofsulfur
Hydrogenolysisofbenzylicheteroatomsreadilyoccursunderpalladium
catalysis;acartoonmechanism
isshown
![Page 27: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/27.jpg)
AromaticandHeterocyclicChemistry
91
AromaticChemistryinAction
SynthesisofLavendamycinanalogues
![Page 28: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/28.jpg)
AromaticandHeterocyclicChemistry
92
AromaticChemistryinAction
SynthesisofLavendamycinanalogues
![Page 29: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/29.jpg)
AromaticandHeterocyclicChemistry
93
AromaticChemistryinAction
SynthesisofLavendamycinanalogues
NHBocN
Me
F
Cl
Me
![Page 30: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/30.jpg)
AromaticandHeterocyclicChemistry
94
AromaticChemistryinAction
SynthesisofLavendamycinanalogues
![Page 31: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/31.jpg)
AromaticandHeterocyclicChemistry
95
AromaticChemistryinAction
Synthesisofathrombininhibitor
Route
1to
fluoro
pyridine
![Page 32: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/32.jpg)
AromaticandHeterocyclicChemistry
96
AromaticChemistryinAction
Synthesisofathrombininhibitor
Route
2to
fluoro
pyridine
![Page 33: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/33.jpg)
AromaticandHeterocyclicChemistry
97
AromaticChemistryinAction
Synthesisofathrombininhibitor
preparationofthepyrazone
![Page 34: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/34.jpg)
AromaticandHeterocyclicChemistry
98
AromaticChemistryinAction
preparationofthepyrazone
![Page 35: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/35.jpg)
AromaticandHeterocyclicChemistry
99
AromaticChemistryinAction
completionofthesynthesis
completedhandoutat:http://burton.chem.ox.ac.uk/teaching.htm
![Page 36: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/36.jpg)
AromaticandHeterocyclicChemistry
100
Problemsfrom
past1Apapers
Providemechanisms,andwhere
appropriate
products,forthefollowingreactions:
![Page 37: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/37.jpg)
AromaticandHeterocyclicChemistry
101
Problemsfrom
past1Apapers
Providemechanisms,andwhere
appropriate
products,forthefollowingreactions:
![Page 38: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/38.jpg)
AromaticandHeterocyclicChemistry
102
Problemsfrom
past1Apapers
Providemechanisms,andwhere
appropriate
products,forthefollowingreactions:
![Page 39: Heteroaromatic Chemistry - stuba.sk › ~szolcsanyi › education › files › Chemia...Heteroaromatic Chemistry Author Peter Szolcsányi Created Date 11/22/2012 4:25:55 PM](https://reader034.vdocuments.us/reader034/viewer/2022052500/5f268a6ce1dbc235bf08bfe1/html5/thumbnails/39.jpg)
AromaticandHeterocyclicChemistry
103
Problemsfrom
past1Apapers
Providemechanisms,andwhere
appropriate
products,forthefollowingreactions:
Forthreeofthefollowingcompounds,suggestasynthesisfromtheunsubstitutedaromaticparentstatedin
parentheses;more
thanonestepmayberequiredineach
case.In
onecase,providemechanismsto
explainthe
transform
ationsusedinyourproposedsynthesis.
Suggestsynthesesofthreeofthefollowingfromeitherbenzeneortoluene(from1Bpaper)