The trans vinylog of benzpinacol in boiling acetic acid undergoes 1, 2-phenyl group migration to give the p,?-unsaturated ketone. The cis isomer is first cyclodehydrated to the 2, bdihydrofuran but is rearranged to the same ketone under more drastic acid catalysis. Rigorous proof of structure of the ketone includes degradations, reactions connecting it with a known compound, and nmr spectrum of its carbinol. Lithium aluminum hydride reduction ...
