POP-Pincer Osmium-Polyhydrides: Head-to-Head (<i>Z</i>)-Dimerization of Terminal Alkynes
作者:Joaquín Alós、Tamara Bolaño、Miguel A. Esteruelas、Montserrat Oliván、Enrique Oñate、Marta Valencia
DOI:10.1021/ic400730a
日期:2013.5.20
both chloride ligands and the hexahydride OsH6xant(PiPr2)2} (7), containing a κ2-P-binding diphosphine, is formed under 3 atm of hydrogen at 50 °C. Complex 7 releases a H2 molecule to yield the tetrahydride OsH4xant(PiPr2)2} (8), which can be also prepared by reaction of OsH6(PiPr3)2 (9) with xant(PiPr2)2. Complex 8 reduces H+ to give, in addition to H2, the oxidized OsH4-species [OsH4(OTf)xant(PiPr2)2}]+
宽范围的锇polyhydride络合物的稳定化由POP-钳配体xant(P我镨2)2(9,9-二甲基-4,5-双(二异丙基)呫吨)已通过合成顺-OsCl 2 κ -小号- (DMSO)4 }(1,DMSO =二甲亚砜)。用二膦在回流下处理该加合物的甲苯溶液,得到OsCl 2 xant(P i Pr 2)2 }(κ- S- DMSO)(2)。在Et 3存在下2与H 2的反应N提供OsH 3 Cl xant(P i Pr 2)2 }(3),也可以通过将xant(P i Pr 2)2添加到不饱和d 4-三氢化物OsH 3 Cl(P )的甲苯溶液中来制备i Pr 3)2(5)。配合物3在90°C时可还原性除去甲苯中的H 2。在二甲亚砜的存在下,生成的一元氢化物被S-供体分子捕获,得到OsHCl xant(P i Pr 2)2 }(κ- S- DMSO)(6)。2与H 2的反应对Brønsted碱是明智的。因此,在对比的Et