107556-75-2Relevant academic research and scientific papers
Properties and x-ray structure of PPN+[cis-HFe(CO)3P(OPh)3]-: An unexpected structural isomer
Ash, Carlton E.,Kim, Christine M.,Darensbourg, Marcetta Y.,Rheingold, Arnold L.
, p. 1357 - 1361 (2008/10/08)
The preparation of [PPN][HFe(CO)3P(OPh)3] (1) has been carried out by using an alcoholic hydroxide reaction with Fe-(CO)4P(OPh)3; the same synthesis was reported earlier for trans-HFe(CO)3PR3- salts. After spectral and chemical differences were observed between the anion of 1 and all other HFe(CO)3PR3- anions, which have been shown to exist in a trans configuration of H and PR3 (TBP geometry), an X-ray structural determination was performed. 1 crystallizes in the triclinic system, space group P1, with cell parameters a = 10.491 (3) ?, b = 13.963 (4) ?, c = 18.687 (6) ?, α = 108.19 (2)°, β = 105.47 (2)°, γ = 93.16 (2)°, V = 2478 (1) ?3, and Z = 2. The hydride ligand was located in the axial position of a distorted trigonal bypyramid, but curiously the P(OPh)3 ligand is in the equatorial plane, cis to the hydride. Unique properties of 1 include its air stability and its rigidity as the cis isomer. The spectral properties of 1 including ion pairing and isotopic H/D exchange effects were examined. In contrast to other anion trigonal-bipyramidal complexes that show equatorial CO?Na+ interaction, an axial CO?Na+ site interaction was observed for 1. Hydrogen/deuterium substitution in this anion revealed a large v(MH) to v(CO) coupling to the trans carbonyl group.
