X-ray and NOE Studies on Trinuclear Iridium Hydride Phosphino Oxazoline (PHOX) Complexes

• Published in: Organometallics Vol. 22; no. 5; pp. 1000 - 1009
• Main Authors: Smidt, Sebastian P, Pfaltz, Andreas, Martínez-Viviente, Eloísa, Pregosin, Paul S, Albinati, Alberto
• Format: Journal Article
• Language: English
• Published: American Chemical Society 03-03-2003
• ISSN: 0276-7333; 1520-6041
• DOI: 10.1021/om020805a

Two trinuclear iridium hydride clusters of the type [Ir3(μ3-H)(H)6(PHOX)3]X1X2 (X1 = PF6, X2 = OTf; X1 = X2 = PF6; X1 = X2 = OTf; PHOX = (S)-4-tert-butyl-2-[2-(di-o-tolylphosphinyl)phenyl]-4,5-dihydrooxazole, (S)-2-[2-(diphenylphosphinyl)phenyl]-4-isopropyl-4,5-dihydrooxazole) have been prepared and characterized by X-ray diffraction and multidimensional NMR. They contain a single bridging hydride in pseudo-trans position to the P-donors. The complexed PHOX ligands reveal a chiral pocket involving one pseudoequatorial P-aryl substituent and one pseudoaxial (proximate to the oxazoline substituent) P-aryl group. These trinuclear complexes are shown to be inactive as hydrogenation catalysts.