Tethered Osmium Boryl Complexes from the Reaction of Os(BCl2)Cl(CO)(PPh3)2 with 2-Hydroxypyridine

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• 作者：Clifton E. F. Rickard ; Warren R. Roper ; Alex Williamson ; and L. James Wright
• 刊名：Organometallics
• 出版年：2002
• 出版时间：April 15, 2002
• 年：2002
• 卷：21
• 期：8
• 页码：1714 - 1718
• 全文大小：74K
• 年卷期：v.21,no.8(April 15, 2002)
• ISSN：1520-6041

文摘

Reaction between Os(BCl₂)Cl(CO)(PPh₃)₂ and 2-hydroxypyridine leads to the replacementof one chloride on the dichloroboryl ligand and coordination of the pyridine nitrogen atomto osmium, leading to the six-coordinate complex Os[BCl(OC₅H₄N)]Cl(CO)(PPh₃)₂ (1). Thefive-membered chelate ring so formed is stable and persists through reactions involvingreplacement of chloride both at osmium and at boron. When 1 is treated with anhydrousHI, replacement of chloride at osmium occurs exclusively, leaving the B-Cl bond intact andgiving Os[BCl(OC₅H₄N)]I(CO)(PPh₃)₂ (2). However, the following nucleophilic substitutionreactions at boron occur readily in 1: EtOH gives Os[B(OEt)(OC₅H₄N)]Cl(CO)(PPh₃)₂ (3),n-BuNH₂ gives Os[B(NHn-Bu)(OC₅H₄N)]Cl(CO)(PPh₃)₂ (4), and Et₃N·3HF gives Os[BF(OC₅H₄N)]Cl(CO)(PPh₃)₂ (5). Crystal structures of complexes 2 and 4 are reported.