PREPARATION OF DIOLEFINS FROM TERTIARY AND SECONDARY ALKYL HALIDES CONTAINING ONLY FOUR CARBON ATOMS IN THE MAIN CHAIN

摘要

There is disclosed a method for the preparation of certain diolefins such as 1,3-butadiene, isoprene and 2,3-dimethyl-1,3-butadiene which comprises simultaneously dehydrohalogenating and dehydrogenating alkyl halides such as 2-halo-butanes, 2-methyl-2-halo-butanes, 3-methyl-2-halo-butanes and 2,3-dimethyl-2-halo-butanes. The process requires the use of catalysts which are preferably metal oxides of groups Ib, IIa, IIb, IIIa, IVa, IVb, Va, Vb, VIb, VIIb, VIII and the lanthanum and actinium series of the Periodic System. Of these metal oxides it is preferred to employ silica and/or alumina.