Nickel(ii) complexes of the new pincer-type unsymmetrical ligands PIMCOP, PIMIOCOP, and NHCCOP: versatile binding motifs
Résumé
Chelation/nickellation of an unsymmetrical meta-phenylene-based ligand featuring phosphinite and imidazolophosphine functionalities gives the corresponding pincer complex. N-Methylation of the latter generates a new complex featuring the ternary moiety NHC→Ph2P+→Ni, which can be converted subsequently into the binary moiety NHC→Ni by extrusion of Ph2P+, thus allowing a sequential synthesis of pincer complexes displaying varying degrees of dipolar character.