Depending on the substituent α-substituted benzylidenecyclopropanes (32) react more or less readily with lithium dust (2% sodium) in diethyl ether whereby a regioselective scission of only the cyclopropane σ-bond cis to the phenyl ring takes place. Upon raising the temperature the primarily formed 1, 3-dilithiumorganic compound due to an agostic interaction rearranges by a 1, 6-proton shift into a doubly bridged 1, 4-dilithio compound. ...