Event Information
Ketone α-functionalization via sulfonyl hydrazone and oxime mediated carbon–carbon bond formation
- Abstract:
The use of diazoalkenes and nitrosoalkenes derived from sulfonyl hydrazones and oximes repectively to effect α-functionalization of ketones is relatively unexplored method which solves many of the shortcomings associated with the traditional methods for ketone α-functionalization and could potentially provide a method for conducting the reaction in a catalytic asymmetric sense. Normally, α-functionalization of ketones is conducted via enolate intermediates where the carbon atom in question is nucleophilic and thus reacts with an appropriate electrophile. Our method for ketone α-functionalization utilizes umpolung reactivity wherein the carbon being derivatized is electrophilic in nature and is attacked by a suitable nucleophile. This methodology relies on the oxidation of sulfonyl hydrazones or oximes to the diazoalkene or nitroso compounds respectively followed by conjugate addition of a cuprate. This report describes our efforts to develop a general and operationally simplified approach to ketone α-functionalization.
Preliminary Examination Seminar
Student Exams Seminar