Reduction of acid chlorides using zirconium borohydride triphenylphosphine complex as a new, efficient and stable reducing agent

Zirconium borohydride triphenylphosphine complex (ZrBTP) is easily prepared in high yield from commercially available starting materials. It is stable under mild aqueous acidic conditions (pH 4 - 6) and survives in H2O for several days without losing its reducing abilities. Its application for the efficient reduction of aliphatic and aromatic acid chlorides is presented.