Synthesis and reactivity of aziridinocarbene complexes of chromium and tungsten: formation of nitrile and acetiminoester complexes

Abstract

2-Methylaziridine H NCH 2C HCH 3 reacts with alkyl- and aryl-(alkoxy)carbene complexes of chromium and tungsten to give alkyl- and aryl-aziridinocarbene complexes. The latter undergo a thermal transformation to give olefins and alkyl- or aryl-nitrilechromium pentacarbonyl complexes, e.g. (CO) 5CrNC- o-tolyl (which has been characterized by X-ray crystallography). 2-Phenylaziridine H NCH 2C HPh in turn reacts with the carbene complexes to give directly styrene and the acetiminoester complexes (CO) 5WHNC(CH 3)OCH 2CH 3 and (CO) 5CrHNC(CH 3)OCH 2-CH 3. The latter gives, upon hydrolysis (CO) 5CrNH 3. The structures of (CO) 5WHNC(CH 3)OCH 2CH 3 and (CO) 5CrNH 3 have been determined by X-ray diffraction. The mechanisms of the two reactions are discussed.