Treatment of benzyl bromoacetate with 3-butenylgallium dichloride in ether in the presence of a catalytic amount of Et3B as a radical initiator provided benzyl 3-cyclopropylpropanoate in 64% yield via a radical addition–substitution sequence. The use of 3-butenylindium dichloride in place of the gallium reagent also afforded the same product in good yield.