79908-21-7Relevant articles and documents
Triphenylphosphaalkenes in Chemical Equilibria
D'Imperio, Nicolas,Arkhypchuk, Anna I.,Mai, Juri,Ott, Sascha
, p. 1562 - 1566 (2019)
Triphenylphosphaalkenes 1a–c were prepared in good to excellent yields in a modified phospha-Peterson reaction between PhP(Li)TMS and benzophenones with different para-substituents at the C-phenyl groups (a: R = H, b: R = O-octyl, c: R = F). Owing to the
PhP=CPh2and Related Phosphaalkenes: A Solution Equilibrium between a Phosphaalkene and a 1,2-Diphosphetane
Wang, Shuai,Samedov, Kerim,Serin, Spencer C.,Gates, Derek P.
, p. 4144 - 4151 (2016/09/16)
The synthesis of phosphaalkenes, ArP=C(R)Ph (1, a: Ar = Ph, R = Ph; b: Ar = o-Tol, R = Ph; c: Ar = Mes, R = H), bearing sterically less hindered substituents is reported. Phosphaalkenes 1a–b were prepared by treating Ph2C=O with ArP(Li)SiMe3, whereas 1c was accessed from the AlCl3-mediated reaction of ArP(SiMe3)2and PhC(O)H. Both 1a and 1b dimerize to afford their respective 1,2-diphosphetanes (2a and 2b). Compound 2a was characterized by X-ray crystallography. Dissolution of pure 2a in THF resulted in a temperature dependent equilibrium with monomer 1a (ΔHo= –94.6 ± 14.6 kJ mol–1; ΔSo= –284 ± 48 J mol–1K–1). Although monomer E/Z-1c was identified in solution by its characteristic downfield31P NMR chemical shift (δ = 247.1, 231.5), it was accompanied by the formation of what we believe are oligomers (δ = –25 to 10 ppm, br.). Attempts to trap phosphaalkenes 1a and 1b by treatment with W(CO)5(MeCN) afforded mixtures of complexes W(CO)5(1a–b) (4a–b) and W(CO)4(1a–b)2(5a–b), the disubstituted species being subjected to X-ray crystallographic characterization (5a).
