Stereospecific Substitution of Silylated Bromoallenes with Organocopper Reagents

摘要

We have shown that the presence of a silicon nucleus controls the regiochemistry of the addition of alkyl cuprates to chiral silabromoallenes. A formal S_N2 nucleophilic substitution of the bromine on an sp~2 carbon is observed to give the corresponding polysubstituted chiral silaalkylallenes. This methodology should be of value for the synthesis of various homochiral compounds.