CONVENIENT SYNTHESIS OF DIENE ZIRCONOCENES AND REGIOSELECTIVE PARTIAL REDUCTION OF THE MORE HIGHLY SUBSTITUTED DOUBLE-BONDS OF CONJUGATED DIENES VIA COMPLEXATION WITH ZIRCONOCENES AND PROTONOLYSIS

Conjugated dienes can be initially converted to their zirconocene complexes most conveniently by their reaction with (C5H5)2ZrCl2 and freshly ground Mg; the resultant complexes can then be protonolysed with 3 mol dm-3 HCl to give regioselectively monoenes corresponding to partial hydrogenation of the more highly substituted double bond.