Abstract: | Reactions of α,β-unsaturated carbonyl compounds with Me3SiCH2MgCl, prepared from chloromethyltrimethylsilane [1], were examined. Unlike its lithium counterpart (Me3SiCH2Li), which adds to α,β-unsaturatedketones in the 1,2-sense, the Grignard reagent afforts γ silanes via a 1,4-addition sequence. This tendency is accentuated by the addition of Cu2Br2. Addition of the Grignard reagent to α,β-unsaturated aldehydes gives the simple 1,2-addition products. |