Direct Carbon-Carbon Bond Formation via Soft Enolization of Thioesters: An Operationally Simple Mannich Addition Reaction

Thioesters undergo soft enolization and direct Mannich additionto sulfonylimines on treatment with magnesium bromide ethyl etherateand N, N-diisopropylethylamine.The reactions proceed readily with a range of sulfonylimines and,in the case of 2,4,6-triisopropylphenyl thiopropionate, give moderateto good SYN dia-stereoselectivity.