P NMR Chemical Shifts of Carbene-Phosphinidene Adducts as an Indicator of the π-Accepting Properties of Carbenes

摘要

Since the discovery of the first stable carbene in 1988 and the seminal report by Arduengo and co-workers in 1991 of the synthesis of a stable imidazol-2-ylidene, the number of stable carbenes has increased tremendously. Of particular interest is their use as ligands for transition metals, which has led to numerous breakthroughs in the field of homogenous catalysis.