Synthesis and characterization of a large bite angle xantphos iridium complex

Abstract

The xantphos iridium complex [Ir(xantphos)(H)(CO)(PPh3)] CH2Cl2 (3) was synthesized and structurally characterized by NMR, IR, and single-crystal X-ray diffraction. Complex 3 crystallizes with two molecules (A,B) in the asymmetric unit. The coordination around Ir is trigonal bipyramidal with all three P groups occupying equatorial positions. The carbonyl and hydride occupy axial sites. This mode of bonding results in a complex that exhibited large bite (P1–Ir–P2) angles of 109.12(6) and 110.50(6)° for the A and B molecules, respectively. NMR data further support the structural elucidation of 3 and IR data confirm the presence of Ir bound to both a carbonyl and a hydride. Thermal analyses of 3 indicate that it is thermally stable up to >400 °C under nitrogen.