DEVELOPING THE PHYSICAL ORGANIC-CHEMISTRY OF FISCHER CARBENE COMPLEXES

Fischer carbene complexes have over the last 25 years become a major f ocus of many synthetic groups. On the other hand, until recently there have been only a few kinetic and/or thermodynamic studies of even the simplest reactions of these complexes. A number of such studies have now been carried out in my laboratory, This review summarizes the resu lts obtained thus far and focuses on three areas: (1) thermodynamic an d kinetic acidities of carbene complexes that contain an ionizable pro ton on the carbon adjacent to the carbene carbon; (2) mechanism and st ructure-reactivity relationships in the reactions of carbene complexes with nucleophiles; (3) mechanism of hydrolysis of carbene complexes w ith and without ionizable protons.