Resumen:
n the dehydrohalogenation of 1,2-dihalo- I,I -diphenylethanes, I, to 2-halo- l,l-diphenylethene, 2, either at 760C or
at 500C, promoted by catalytic amount of the snhydrons bromides of Fe(IIl), Ru(llI) and AI(III) and Fe(lll) chloride the
~ical Irnnsformation of the metal halides was observed, In reactions carried out in vacuum or under nitrogen atmosphere,
the hydrogen halide eliminated from the organic substrate reacted with the metal halides rendering the unstable hydrogen
perhalometalates H÷.IMXsJ ". We demonstrate that these compounds behave as hydrogen halide donors in the
hydrohalogenation ofolefms at 4 GRADOS