Reactions of 2-Chloroacyltrimethylsilanes with Grignard Reagents. Preparation of 3-(Trimethylsilyl)-2-alkanones and 2-(Trimethylsilyl)-1-alkanols

Reactions of 2-chloroacyltrimethylsilanes with Grignard reagents have been examined. Thus, treatment with methylmagnesium iodide affords the corresponding 3-(trimethylsilyl)-2-alkanones through an initial addition followed by removal of chloride anion and 1,2-rearrangement of silyl group. In contrast, the reaction proceeds with 2 equiv of the Grignard reagents bearing β-hydrogen to give 2-(trimethylsilyl)-1-alkanols, where initial reduction of the silylcarbonyl group followed by such rearrangement and addition of the Grignard reagents to the resulting 2-(trimethylsilyl)alkanals have been proposed.