interaction between the bridgehead double bond (Cγ) and the opposite bridgehead carbon (Cα), being the homoallylic position of the double bond. From the product study and the kinetic results of the solvolysis of the bridgehead chlorides 1d–3d, it is indicated that the homoallylic participation of the strainedbridgehead double bond to the carbonium ion center located at the opposite bridgehead position operates