88453-33-2Relevant academic research and scientific papers
(Phosphinoalkyl)silyl complexes. 5. Synthesis and reactivity of congeneric chelate-stabilized disilyl complexes of rhodium(III) and iridium(III): Chlorobis[[(diphenylphosphino)ethyl]dimethylsilyl]rhodium and -iridium
Auburn, Mary J.,Stobart, Stephen R.
, p. 318 - 323 (2008/10/08)
Reaction of [M(COD)Cl]2 (M = Rh. Ir; COP = cycloocta-1,5-diene) with excess PPh2CH2CH2SiMe2H in THF solution affords the 5-coordinate M(III) complexes M(PPh2CH2CH2SiMe2)2Cl (1, M = Rh; 2, M = Ir), which are enantiomeric with the two P atoms trans; the common geometry for 1 and 2 deduced from spectroscopic data has been substantiated with X-ray diffraction that shows crystals of the two compounds to be isomorphous. Halide ion exchange reactions yield the analogues 3-6 M(PPh2CH2CH2SiMe2)2X in which X = Br or I. Treatment of [Ir(COD)Cl]2 with 2 mol equiv of PPh2CH2CH2SiMe2H allows the 6-coordinate intermediate Ir(PPh2CH2CH2SiMe2)(COD)(H)(Cl) (7) to be recovered, in which the chelating ligands occupy a plane with H and Cl mutually trans and from which chel (diphos, dpm, PPh2CH2CH2SiMe2H) displaces COD, yielding respectively Ir(PPh2CH2CH2SiMe2) (chel) (H) (Cl) (8, diphos; 9, dpm) or compound 2, although under similar reaction conditions a Rh analogue of 7 could not be obtained. The coordinatively unsaturated Ir complex 2 reacts rapidly with a variety of neutral molecules (CO, PF3, P[OR]3, RNC), generating 6-coordinate adducts as single isomers possessing a common structure with L entering cis to Cl, trans to Si; with L = t-BuNC, Me3CCH2CMe2NC, or Me2CHNC, Rh analogues 10-12 are also formed from 1. Compounds 1 and 10-12 offer the first fully characterized examples respectively of bis(silyl)rhodium, octahedral silylrhodium species, the stability of which contrasts remarkably with the sensitivity toward dissociative cleavage of unsupported Si-Rh bonds. Conversion of 1 or 2 to the corresponding hydrido complexes M(PPh2CH2CH2SiMe2)2H (23, M = Rh; 24, M = Ir) has been demonstrated in solution with NMR spectroscopy, and although the structures of these species remain uncertain since attempted isolation leads to decomposition, compound 24 has been intercepted to form 6-coordinate CO or t-BuNC adducts.
(Phosphinoalkyl)silyl Complexes. 3. "Chelate-Assisted" Hydrosilylation: Formation of Enantiomeric and Diastereoisomeric Iridium(III) Complexes With Chelating (Phosphinoethyl)silyl Ligands
Auburn, Mary J.,Holmes-Smith, Rupert D.,Stobart, Stephen R.
, p. 1314 - 1318 (2007/10/02)
Reaction of trans- with the functionalized silanes PPh2CH2CH2SiR1R2H (R1 = R2 = Me or Ph; R1 = Me, R2 = Ph; or R1 = Me or Ph, R2 = H) occurs immedia
