square-pyramidal [CoI(p2)2]+ complex. The catalytic activity for the Co-catalyzed coupling reaction of 2-iodobutane with n-butyl acrylate was compared using multidentate phosphines and phosphine sulfides as ligands, and the efficiency of the phosphine sulfides was shown. The tendency for multidentate phosphine to deactivate the Co-catalysis can substantiate an oxidative addition driven mechanism in which the multidentate
摘要利用[PdI(pp3)] I的选择性
硫化反应,制备了两个末端膦基被选择性
硫化的三[2-(
二苯基膦基)乙基]膦二
硫化物(pp3S2)。由无
水CoI2制备具有二齿,三齿和四齿膦和pp3S2的Co(II)配合物。X射线晶体分析表明, 与1当量的1,2-双(
二苯基膦基)
乙烷(p2)的反应引起p2的部分氧化,从而生成了双阳离子八面体[Co(p2O2)2(CH3CN)2]。 2+(p2O2 = p2
二氧化碳)和双阴离子p2O桥联的四面体双核[CoI3(p2O)CoI3] 2-(p2O = p2一氧化物)配合物,而与2当量p2的反应给出了方形
金字塔形[CoI(p2) 2] +复合体。以多齿膦和
硫化膦为
配体,比较了
2-碘丁烷与
丙烯酸正丁酯的共催化偶联反应的催化活性,并显示了
硫化膦的效率。多齿膦使共催化失活的趋势可以证实氧化加成驱动的机理,其中多齿
配体应干扰烷基卤化物Co(III)加合物的形成和随后烯烃的配位。