Mechanistic studies of the reaction between α-cyclopropylbenzyl alcohol and methyl-lithium followed by hexamethyldisilane indicate that disproportionation of intermediate (4) with trimethylsilyl anion as catalyst provides cyclopropyl phenyl ketone; in situ 1, 4-addition of trimethylsilyl anion to the latter compound leads to the major product, γ- trimethylsilylbutyrophenone (2).