Baker, Paul K.; Flower, Kevin R.; Drew, Michael G. B., Organometallics, 1993, vol. 12, # 2, p. 276 - 282
作者:Baker, Paul K.、Flower, Kevin R.、Drew, Michael G. B.
DOI:——
日期:——
The synthesis and spectral properties of the new bis(but-2-yne) and mono(but-2-yne) complexes [w(co)l(s2CNC4H8)(η2-MeC2Me)2][BPh4] and [W(CO)L2(S2CNC4H8)(η2-MeC2Me)][BPh4] (where = imidazole, 2-methylimidazole and 4-methylimidazole)
作者:Paul K. Baker、Kevin R. Flower
DOI:10.1016/s0277-5387(00)83758-4
日期:1991.1
Reactions of the complex [W(CO)(NCMe)(S2CNC4H8)(eta-2-MeC2Me)2][BPh4] with one equivalent of L (L = imidazole, 2-methylimidazole or 4-methylimidazole) in the presence of excess but-2-yne at room temperature in CH2Cl2 affords good yields of the bis(but-2-yne) complexes [W(CO)L(S2CNC4H8)(eta-2-MeC2Me)2][BPh4] (1-3). Whereas, reaction of [W(CO)(NCMe)(S2CNC4H8)(eta-2-MeC2Me)2][BPh4] with two equivalents of L (L = imidazole, 2-methylimidazole or 4-methylimidazole) affords high yields of the new mono(but-2-yne) complexes [W(CO)L2(S2CNC4H8)(eta-2-MeC2Me)][BPh4] (4-6). C-13 NMR spectroscopy indicates that the but-2-yne ligands in 1 are donating a total of six electrons to the tungsten, whereas in 4-6 the but-2-yne is donating four electrons to the tungsten. Variable-temperature H-1 NMR studies have been carried out on 4-6 in order to calculate the barrier to but-2-yne rotation.