Construction of Tetrasubstituted Carbon by an Organocatalyst: Cyanation Reaction of Ketones and Ketimines Catalyzed by a Nucleophilic N-Heterocyclic Carbene

Abstract

A method for cyanation reaction of ketones and ketimines having lower reactivity than aldehydes and aldimines with TMSCN in the presence of N-heterocyclic carbene prepared from 1,3-bis(2,4,6-trimethylphenyl)imidazolium chloride and potassium tert-butoxide, as a nucleophilic organocatalyst, is described. These cyanations of ketones and ketimines afford the corresponding products in good yields under mild reaction conditions.

Keywords

N-heterocyclic carbene - tetrasubstituted carbon - nucleophilic organocatalyst - cyanation - trimethylsilyl cyanide

References

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We have already found that DMF is a good solvent for accelerating the cyanation of aldehydes and aldimines. See ref. 2.