Sulfonyl carbanions in synthesis. I. A novel route to α,β-unsaturated carbonyl compounds.

✍ Scribed by Kiyosi Kondo; Daiei Tunemoto

• Publisher: Elsevier Science
• Year: 1975
• Tongue: French
• Weight: 209 KB
• Volume: 16
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)72629-3

✦ Synopsis

Michael-type addition of nucleophiles to a,b-unsaturated carbonyl compounds is a well-known reaction. This means that the B-carbon of the system can only act as an electrophile and never as a nucleophile. We have found, however, that the situation can be changed by ( 1) the introduction of benzenesulfonyl group to the B-carbon by normal Michael addition, and (2) protection of the acyl group by acetalization or ketalization. The resulting sulfone acetal or ketal now