Synthesis and Characterization of 1,2‐Azaborine‐Containing Phosphine Ligands: A Comparative Electronic Structure Analysis

The synthesis and characterization of two 1,2-azaborine-containing phosphine ligands are described. The structural and electronic parameters of the two ligands were compared with those of their direct all-carbon analogues using X-ray crystallography and UV-photoelectron and IR spectroscopy. Our results indicate that the azaborine-containing ligands are significantly stronger electron donors than their corresponding carbonaceous counterparts, while the steric parameters remain similar.