211570-62-6Relevant academic research and scientific papers
Novel synthesis, X-ray crystal structures, and spectroscopic properties of metalated hypervalent phosphorus compounds, Cp(CO)LFe{P(OC6H4Y)OC6H4Z} (L = CO, P(OPh)3, P(OMe)3, PMe3; Y, Z = NH, NMe, O)
Kubo, Kazuyuki,Nakazawa, Hiroshi,Mizuta, Tsutomu,Miyoshi, Katsuhiko
, p. 3522 - 3531 (1998)
Iron phosphorane complexes, Cp(CO)2Fe{P(OC6H4Y)2} (1a, Y = NH; 1b, Y = NMe; 3, Y = O), have been prepared from [Cp(CO)2Fe{P(OPh)3}]PF6, o-HOC6H4YH, and a Lewis base. Cp(CO)2Fe{P(OC6H4O)(OC6H 4NR)} (2a, R = H; 2b, R = Me) having two different chelates on the phosphorus has been prepared from [Cp(CO)2Fe{P(OC6H4O)(OPh)}]PF6, o-HOC6H4-NRH, and a Lewis base. These reactions involve nucleophilic attacks of an organic nucleophile at a trivalent phosphorus coordinated to an iron and substitution on the phosphorus. During the course of preparation of 1b, [Cp(CO)2Fe{P(OC6H4NMe)-(OC6H 4NMeH)}]PF6 (4) was isolated, which corresponds to one of the intermediates on the reaction pathways to give 1-3. 4 reacts with a Lewis base to give 1b. The reaction of hydridophosphorane HP(OC6H4NH)2 with n-BuLi leads to NH proton abstraction to give the amide HP(OC6H4NH)(OC6H4N-), which then reacts with Cp(CO)LFeCl to yield Cp(CO)-LFe{P(OC6H4NH)2} (5, L = P(OPh)3; 6, L = P(OMe)3; 7, L = PMe3) by an apparent 1,2-proton migration. The X-ray structures of 1b, 2b, and 4 were determined. 1b and 2b have slightly distorted trigonal-bipyramidal geometries around the phosphorus with the iron fragment in the equatorial position and have P-Oeq bonds longer than those of organophosphoranes, indicating that the Cp(CO)2Fe fragment serves as a strong π donor. The Fe-P(phosphorane) bond rotates freely in solution even at -50°C. A Berry pseudorotation around the phosphorane phosphorus does not occur for 1a,b, 2a,b, and 5-7, whereas it does for 3.
