Conclusions We were the first to effect the enantioselective hydrogenation of a mixture of isomeric 2-phenylbutenes on chiral cobalt catalytic systems of the Ziegler-Natta type in an optical yield of 25%.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2621–2622, November, 1981.