Pincer Phosphine Complexes of Ruthenium: Formation of Ru(P−O−P)(PPh3)HCl (P−O−P = xantphos, DPEphos, (Ph2PCH2CH2)2O) and

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• 作者：Araminta E. W. Ledger ; Aitor Moreno ; Charles E. Ellul ; Mary F. Mahon ; Paul S. Pregosin ; Michael K. Whittlesey ; Jonathan M. J. Williams
• 刊名：Inorganic Chemistry
• 出版年：2010
• 出版时间：August 16, 2010
• 年：2010
• 卷：49
• 期：16
• 页码：7244-7256
• 全文大小：1277K
• 年卷期：v.49,no.16(August 16, 2010)
• ISSN：1520-510X

文摘

Treatment of Ru(PPh₃)₃HCl with the pincer phosphines 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene (xantphos), bis(2-diphenylphosphinophenyl)ether (DPEphos), or (Ph₂PCH₂CH₂)₂O affords Ru(P−O−P)(PPh₃)HCl (xantphos, 1a; DPEphos, 1b; (Ph₂PCH₂CH₂)₂O, 1c). The X-ray crystal structures of 1a−c show that all three P−O−P ligands coordinate in a tridentate manner through phosphorus and oxygen. Abstraction of the chloride ligand from 1a−c by NaBAr₄^F (BAr₄^F = B(3,5-C₆H₃(CF₃)₂)₄) gives the cationic aqua complexes [Ru(P−O−P)(PPh₃)(H₂O)H]BAr₄^F (3a−c). Removal of chloride from 1a by AgOTf yields Ru(xantphos)(PPh₃)H(OTf) (2a), which reacts with water to form [Ru(xantphos)(PPh₃)(H₂O)H](OTf). The aqua complexes 3a−b react with O₂ to generate [Ru(xantphos)(PPh₃)(η²-O₂)H]BAr₄^F (5a) and [Ru(DPEphos)(PPh₃)(η²-O₂)H]BAr₄^F (5b). Addition of H₂ or N₂ to 3a−c yields the thermally unstable dihydrogen and dinitrogen species [Ru(P−O−P)(PPh₃)(η²-H₂)H]BAr₄^F (6a−c) and [Ru(P−O−P)(PPh₃)(N₂)H]BAr₄^F (7a−c), which have been characterized by multinuclear NMR spectroscopy at low temperature. Ru(PPh₃)₃HCl reacts with 1,1′-bis(diphenylphosphino)ferrocene (dppf) to give the 16-electron complex Ru(dppf)(PPh₃)HCl (1d), which upon treatment with NaBAr₄^F, affords [Ru(dppf){(η⁶-C₆H₅)PPh₂}H]BAr₄^F (8), in which the PPh₃ ligand binds η⁶ through one of the PPh₃ phenyl rings. Reaction of 8 with CO or PMe₃ at elevated temperatures yields the 18-electron products [Ru(dppf)(PPh₃)(CO)₂H]BAr^F₄ (9) and [Ru(PMe₃)₅H]BAr₄^F (10).