1,4-Asymmetric reduction of γ-keto sulfoxides bearing the 2,4,6-triisopropylphenyl group
Abstract
Reduction of γ-keto sulfoxides bearing the 2,4,6-triisopropylphenyl group with DIBAL gives γ-hydroxy sulfoxides with high stereoselectivity in the ratio 95∶5. In comparison with the lower stereoselectivities obtained in the reaction of γ-keto sulfoxides bearing p-tolyl or 2,4,6-trimethylphenyl groups, the sterically bulky (2,4,6-triisopropylphenyl)sulfinyl group is extremely efficient in effecting high 1,4-remote asymmetric induction.