Abstract
The reaction of [Li(Et 2O) 2][Cp′ 2MCl 2] (Cp′ = C 5Me 5; M = Nd, Sm) with 1 equivalent of Li(CH 2)(CH 2)PRR′( a, R = Me, R′ = Ph; b, R = R′= Ph; c, R = R′= Me; d, R = R′ = t-Bu) produces Cp′ 2M[(CH 2)(CH 2)PPR′]·(LiCl) 2 ( I, M = Sm; II, M = Nd) in moderate yield. Variable-temperature 1H NMR studies on Cp′ 2M[(CH 2)(CH 2)P(Me)R]·(LiCl) 2 (M = Nd, Sm; R = Me, Ph) show that the methyl protons on the phosphorus of the chelating ylide undergo rapid exchange with the bridging methylene protons even at −40°C. A mechanism which is based on a series of metal—carbon bond breaking, rotation and recombination processes has been proposed for the fluxional behaviour. The ylidic complexes react with hydrogen (1 atm) at ambient temperature producing C 5Me 5H and the corresponding phosphonium salts, [RR′PMe 2]Cl. 1H NMR studies on the reactivity of Ia towards hydrogen and acid review that the metal—carbon bond formed between the lanthanide metal and the chelating phosphorus ylide is more stable than that formed between the lanthanide metal and the pentamethylcyclopentadienyl ring.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
