Reaction of a zero-valent ruthenium complex [Ru(cot)(cod)] 1 (cod = 1,5-cyclooctadiene; cot = 1,3,5-cyclooctatriene) with alkyl cyanoacetate in the presence of mono- and bi-dentate tertiary phosphines gave a series of hydrido(enolato)ruthenium(II) complexes: mer-[RuH(NCCHCO2Et)(NCCH2CO2Et)(PPh3)3] 2; trans-[RuH(NCCHCO2Et)(cod)(dppe)] 3 (dppe = Ph2PCH2CH2PPh2); trans-[RuH(NCCR1CO2R2)(dppe)2] (R1 = H, R2 = Et 4a: or Pri 4b; R1 = Me, R2 = Et 4c) and trans-[RuH(NCCMeCO2Et)(PMePh2)4] 5. The molecular structure of 3 shows that the enolato ligand co-ordinates to the ruthenium centre via the cyano group in an octahedral geometry. These hydrido(enolato)ruthenium(II) complexes catalyse Michael and Knöevenagel reactions under neutral and mild conditions.
零价
钌配合物[Ru(cot)(cod)] 1(cod =
1,5-环辛二烯;cot = 1,3,5-环辛
三烯)与
氰乙酸烷基酯在单齿和双齿叔膦存在下发生反应,生成了一系列氢rido(enolato)
钌(II)配合物:mer-[RuH(NCCHCO2Et)(NCCH2CO2Et)(PPh3)3]2;trans-[RuH(NCCHCO2Et)(cod)(dppe)]3(dppe = Ph2PCH2CH2PPh2);trans-[RuH(NCCR1CO2R2)(dppe)2](R1 = H,R2 = Et 4a:或 Pri 4b;R1 = Me,R2 = Et 4c)和反式-[RuH(NCCMeCO2Et)(PMePh2)4] 5。3 的分子结构显示,烯醇
配体通过
氰基以八面体几何形状与
钌中心配位。这些氢rido(enolato)
钌(II)配合物在中性和温和条件下可催化迈克尔反应和 Knöevenagel 反应。