Addition of prochiral sulfonyl anions to N-sulfinyl ketimines and aldimines

ORGN 75

Francisco Velazquez, francisco.velazquez@spcorp.com1, Ashok Arasappan, ashok.arasappan@spcorp.com1, Kevin Chen, kevin.chen@spcorp.com1, M. Sannigrahi1, Srikanth Venkatraman, Srikanth.Venkatraman@spcorp.com1, Andrew T. McPhail2, Tze-Ming Chan1, Neng-Yang Shih1, and F. George Njoroge, george.njoroge@spcorp.com1. (1) Chemical Research Department, Schering-Plough Research Institute, 2015 Galloping Hill Road, K-15-3 3545, Kenilworth, NJ 07033-1300, (2) Department of Chemistry, Duke University, P. M. Gross Chemistry Laboratory, Durham, NC 27708
The addition of lithiated sulfones and sulfonamides to N-sulfinyl ketimines and aldimines was investigated. Prochiral sulfonyl anions were obtained by deprotonation of the corresponding sulfones and sulfonamides and were added to N-sulfinyl aldimines at low temperature to give addition products with excellent stereocontrol. However, addition of prochiral sulfonyl anions to N-sulfinyl ketimines gave the addition products with moderate selectivity. The stereochemical assignments for the newly created stereogenic centers were made by single crystal X-ray analysis. The stereochemical outcome of the addition reactions will be discussed. The N-sulfinyl group in the addition products was cleaved under acidic conditions to yield optically active beta-amino sulfones and sulfonamides which are present in various pharmaceutical agents.

 

Asymmetric Reactions and Syntheses
1:00 PM-5:00 PM, Sunday, 10 September 2006 Moscone Center -- Room 131, Oral

Division of Organic Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006