653601-59-3Relevant academic research and scientific papers
Synthesis, coordination chemistry and reactivity of cyano-functionalised N-pyrrolyl phosphines
Burrows, Andrew D.,Mahon, Mary F.,Varrone, Maurizio
, p. 152 - 162 (2008/10/08)
The cyano-functionalised N-pyrrolyl phosphines PPh2(NC 4H3CN-2) (L1) and P(NC4H 4)2(NC4H3CN-2) (L2) have been prepared from the reaction of PClR2 (R=Ph, NC4H 4) with lithium 2-cyanopyrrolide, itself generated in situ from 2-cyanopyrrole and BuLi. The reaction of L1 or L2 with [MCl2(cod)] gives [MCl2(L-κ1P) 2] (1, M=Pt, L=L1; 2, M=Pd, L=L1; 3, M=Pt, L=L2; 4, M=Pd, L=L2) and both cis-1 and trans-4 have been structurally characterised. The crystal structure of cis-1 reveals the presence of an unusually wide P-Pt-P angle [107.22(5)°], which has its origin in an intramolecular interaction between the two 2-cyanopyrrole rings. The reaction of L1 with [M(dmba)(μ-Cl)]2 (Hdmba=N,N- dimethylbenzylamine) results in formation of [MCl(dmba)(L1- κ1P)] (5, M=Pt; 6, M=Pd). Compounds 5 and 6 react with TlPF6 to give oligomeric P,N-coordinated compounds of empirical formula [M(dmba)(L1)][PF6]. The dimeric compound [Pt(dmba)(μ-L1-κ1P,κ1N)] 2(PF6)2 (7), has been isolated and structurally characterised, and coordination of the cyano groups leads to formation of a 12-membered ring. Compound 6 reacts with PhCH2 CH(NH2)CH2OH in the presence of TlPF6 to yield [Pd(dmba)(PPh2NC4H3{C=NCH(CH 2Ph)CH2O-2})]PF6 (8) in which the cyano group has been transformed into an oxazoline group. The molybdenum complex [MoCl(CO)3(η5-C5H5)] reacts with L1 to give [MoCl(CO)2(L1-κ 1P)(η5-C5H5)] (9) which has been structurally characterised. In contrast to the reaction of 5 or 6, compound 9 does not react with TlPF6 or AgBF4 to give tractable oligomeric products. Reaction of the rhodium complex [Rh(acac)(CO)2] with L1 occurs to give [Rh(acac)(CO)(L1-κ1P)] (10). The infrared spectrum of 10 indicates the electronic properties of L1 are very similar to those for PPh2(NC4H4).
