An effective method for controlling 3,4-stereochemistry of aldols. Direct preparation of optically active 2,3-anti-3-hydroxy-2-methyl carbonyl compounds

Abstract

Both 3,4-syn- and 3,4-anti-aldols can be prepared selectively from 2-methyl-3-trimethylsilylalk-3-enyl carbonyl compounds via 1,2-asymmetric induction; thus optically active 2,3-anti-3-hydroxy-2-methyl carbonyl compounds can be prepared by the reaction of optically active (R)-2-methyl-3-trimethylsilylbut-3-enal (1) with the lithium enolate of 2,6-di-t-butyl-4-methylphenyl propionate.