Hydrochlorination of Ruthenaphosphaalkenyls: Unexpectedly Facile Access to Alkylchlorohydrophosphane Complexes
Organometallics(2017)
摘要
The novel ruthenaphosphaalkenyls [Ru{P═C(H)SiMe2R}Cl(CO)(PPh3)2] (R = p-C6H4CF3, nBu) have been prepared for the first time, and studied alongside precedent analogues (R = Me, Ph, p-tol) for their reactions with HCl. In contrast to chemistry defined for the tert-butyl congener [Ru{P═C(H)tBu}Cl(CO)(PPh3)2], which initially adds a single equivalent of HCl across the Ru–P linkage, all five silyl derivatives undergo spontaneous addition of a second equivalent to afford [Ru{η1-PHCl–CH2SiMe2R}Cl(CO)(PPh3)2], extremely rare examples of coordinated “PHXR” type ligands. Where R = SiMe3, a distorted octahedral geometry with a conformationally restricted “PHXR” ligand is observed crystallographically; this structure is appreciably retained in solution, as determined from multinuclear NMR spectroscopic features, which include a Karplus-like PPPh3–Ru–P–H spin–spin coupling dependence. Computational data suggest a silyl-induced increase in negative charge density at the phosphaalkenic carbon, rather than an intrinsic thermodynamic driver, as the likely origin of the disparate reactivity.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要