title: Syntheses of PBP pincer iridium complexes: a supporting boryl ligand.
abstract: We synthesized a PBP pincer ligand precursor 2 and demonstrated its complexation with iridium(I) to afford the coordinatively unsaturated [PBP](hydrido)chloroiridium complex 3 via B-H oxidative addition. The reaction of 3 with carbon monoxide produced [PBP](hydrido)chloro(carbonyl)iridium 7. The longer Ir-Cl bond length of 7 than that of 8 revealed a stronger sigma-donor ability of the PBP ligand than that of PCP. Complex 3 was also converted to [PBP](ethylene)iridium(I) complex 9 by the reaction with LiTMP under an ethylene atmosphere.
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo 7-3-1, Hongo, Bunkyo-ku, 113-8656 Tokyo, Japan.
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Segawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Yamashita
authors.forename: Kyoko
authors.initials: K
authors.lastname: Nozaki