High diastereoselective Michael and aldol additions of Fischer-type alkyl(hydrazino)carbene complexes: synthesis of new hydrazides

The addition of the enolate, generated from the tetracarbonylethyl(hydrazino)carbene chromium complex 6, to achiral enones and aldehydes gave the corresponding Michael and aldol adducts in very high chemical yield and d.e.. Some of the new δ-keto and β-hydroxy hydrazino carbene complexes have been oxidised to give the corresponding hydrazides in high yield. A spectroscopic study to establish the geometry of the enolate generated from 6 has also been performed.