8 - Carbonylation and Other Reactions

Abstract

A comparatively recent and extremely valuable extension of phase-transfer catalysis is to be found in its application to the chemistry of metal carbonyls, which crosses the boundaries of inorganic chemistry, through organometallic chemistry, and into organic chemistry. The basic chemistry of transition metal carbonyls has been reviewed extensively and many of the procedures, which are of value in synthetic organic chemistry, have been reported to be frequently tedious and invariably involve prolonged reaction times, high temperatures, and high pressures of carbon monoxide. The first significant reports of the use of phase-transfer catalysis with metal carbonyls describe the simple in situ formation of the cobalt tetracarbonyl anion from dicobalt octacarbonyl. Kinetic studies indicate that the conversion of the dicobalt octacarbonyl into the cobalt tetracarbonyl anion at room temperature and the subsequent formation of the n-allyl complex are complete within 15 minutes. In the absence of the phase-transfer catalyst, no Π-allyl complex is formed. In a similar manner, n-allyl complexes of manganese, iron, and molybdenum carbonyls have been obtained from the corresponding metal carbonyl halides.