Bis (~ 5-cyclopentadienyl) zirconium (IV) complexes, Cp2ZrH2 (1) and Cp2Zr (Oi-Pr) 2 (4), in the presence of an appropriate hydrogen acceptor such as benzaldehyde or cyclohexanone catalyze the Oppenauer-type oxidation of allylic alcohols to a, P-unsaturated carbonyl compounds. For instance, primary allylic terpenoid alcohols, geraniol and nerol, were oxidized to a-and@ citrals, which are essential compounds in the perfumery industry, in ...
