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Cascade  Reactions  

Magnus  Pfaffenbach  Gaich-­‐Group  Seminar  November  12,  2012  

Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Overview and Definition

Definition (strict): A cascade reaction is a process in which several bonds are formed in sequence without isolating intermediates, changing conditions or adding reagents.

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Pro and Contra

Practical Advantages: -  Atom economy -  Reduction of time, labor, waste and resources -  „Green Chemistry“

Academic Considerations: -  Fast access to structures with increased complexity -  Aesthetic appeal to synthetic planning

Disadvantages: -  Synthesis of precursors often far from trivial -  Few examples of catalytic enantioselective cascade reactions

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Classic Examples

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Classic Examples

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Classic Examples

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Classic Examples

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Nucleophilic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Nucleophilic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Electrophilic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Electrophilic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Electrophilic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Radical Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Radical Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Pericyclic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Pericyclic Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Transition Metal-Catalyzed Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Diazo Compound Initiated Cascades

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Gaich-­‐Group  Seminar  Magnus  Pfaffenbach  

Thank you for your attention!

Questions?