화학공학소재연구정보센터
Inorganic Chemistry, Vol.52, No.16, 9583-9589, 2013
Multimetallic Complexes Featuring a Bridging N-heterocyclic Phosphido/Phosphenium Ligand: Synthesis, Structure, and Theoretical Investigation
By incorporating an N-heterocyclic phosphenium/phosphide (NHP) ligand into a chelating pincer ligand framework (PPP+/PPP-), we have elucidated several different and unprecedented binding modes of NHP ligands in homobimetallic, heterobimetallic, and trimetallic metal complexes. One-electron reduction of the previously reported (PPP)(-)/M-II complexes (PPP)M-Cl (M = Pd (1), Pt (2)) results in clean formation of the symmetric homobimetallic M-I/M-I complexes [(mu-PPP)Pd](2) (5) and [(mu-PPP)Pt](2) (6). The tridentate NHP ligand has also been utilized as a bridging linker in the M/Co heterobimetallic compounds (OC)(3)Co(u-PPP)M(CO) (M = Pd (7), Pt (8)), synthesized via salt elimination from mixtures of 1 and 2 and Na[Co(CO)(4)]. Furthermore, an NHP-bridged trimetallic complex (PPP)(2)Pd3Cl2 (9) can be synthesized in a manner similar to precursor 1 (Pd(PPh3)(4) + (PPP)Cl) via careful adjustment of reaction stoichiometry. Examination of the interatomic distances and angles in complexes 5-9, in tandem with density functional theory calculations have been used to evaluate and characterize the bonding interactions in these complexes.