PhCHXX1 (I where X = H, X1 = F or Cl; X = X1 = Br; or X = B r, X1 = F) were treated with BuLi and cyclohexene (II) to give syn-7 - phenylnorcarane (III) and its anti isomer (IV). The III/IV ratio was detd. relative to the nature of I, the concn. of II, and the influence of a solvent. Phenylcarbene PhCH: may be the intermediate. [on SciFinder (R)]