CH= CHCtt Brl a The yields are, where not otherwise stated, based on the olefin. d Yield of total mixture of I11 and IV. adducts B, in order to study their reactions with alkyllithium. We had previously shown that alkyl-and aryl-substituted gem-dibroniocyclopropanes reacted readily with methyl-or n-butyllithiuni to give, in niost cases, good yields of allenes. K Similar results were also independently obtained by Moore and Ward. $
