Abstract
A one-pot procedure for the reductive alkylation of β-keto sulfones is described. The method proceeds by a lithium in liquid ammonia desulfurization of the starting β-keto sulfone, resulting in regiospecific generation of an intermediate enolate. Subsequent admixture of tributyltin chloride followed by addition of the alkylating agent in HMPA generates the C(α)-alkylated product in good yield and with excellent regiocontrol. Thus, 2-(phenylsulfonyl)-5-(2-propenyl)cyclopentanone gives 2,5-di(2-propenyl)cyclopentanone in 71% isolated yield with <1% of 2,2-di(2-propenyl)cyclopentanone detected in the crude reaction mixture. Experiments are presented which underscore the advantages of this procedure over traditional α-alkylation/desulfurization protocols.
Original language | English (US) |
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Pages (from-to) | 3846-3848 |
Number of pages | 3 |
Journal | Journal of Organic Chemistry |
Volume | 50 |
Issue number | 20 |
State | Published - 1985 |
ASJC Scopus subject areas
- Organic Chemistry