101348-82-7Relevant academic research and scientific papers
Synthesis and structure of three (tricyclohexylphosphine)rhodium complexes and their interconversion with carbon monoxide and hydrogen
Freeman, Michael A.,Young, David A.
, p. 1556 - 1560 (2008/10/08)
The reaction of Rh(CO)2acac with CO and H2 in the presence of excess tricyclohexylphosphine (PCy3) gave an easily separated mixture of HRh(CO)(PCy3)2 (3) and (PCy3)2Rh(μ-CO)2Rh(CO)PCy3 (7). The structures of 3 and 7 were determined by X-ray crystallography and related to appropriate structures previously reported. Crystal data for 3: monoclinic, P21/c (C2h5, No. 14), a = 10.066 (2) A?, b = 15.910 (4) A?, c = 23.438 (6) A?, a = 90.00°, β = 94.13 (2)°, γ = 90.00°, Z = 4. Crystal data for 7: triclinic, P1 (Ci1), a = 13.681 (3) A?, b = 14.261 (4) A?, c = 19.235 (5) A?, a = 104.15 (2)°, β= 99.70 (2)°, γ = 84.98 (2)°, Z = 2. 3 has a trans square-planar configuration. 7 contains a square-planar Rh(CO)PCy3 and a distorted-tetrahedral Rh(PCy3)2. The 31P NMR spectra of 7 indicated an intramolecular geminal phosphine site exchange process on Rh(PCy3)2. 3 and 7 both react with CO, forming PCy3(CO)2Rh(μ-CO)2Rh(CO)2PCy 3 (8), which was stable only in the presence of CO, reverting back to 7 in the absence of CO. 7 reacted with H2, re-forming 3.
