Novel tridentate diamino organomanganese(II) complexes as homogeneous catalysts in manganese(II)/copper(I) catalyzed carbon–carbon bond forming reactions
作者:Johannes G Donkervoort、José L Vicario、Johann T.B.H Jastrzebski、Robert A Gossage、Gérard Cahiez、Gerard van Koten
DOI:10.1016/s0022-328x(97)00675-x
日期:1998.5
paramagnetic arylmanganese(II) complex Li[MnCl2(NCN)] (2, NCN [C6H3(CH2NMe2)2-2,6]−) has been obtained in high yield from the reaction of MnCl2 and [Li(NCN)]2 in a 2:1 molar ratio. In THF solution, 2 is likely an ionic species [Li(THF)n] [MnCl2(NCN)] (molecular weight determination and conductivity measurements), while magnetic measurements indicate that a high spin d5 manganese(II) center is present. Subsequent
新型的顺磁性芳基锰(II)络合物Li [MnCl 2(NCN)](2,NCN [C 6 H 3(CH 2 NMe 2)2 -2,6] -)是通过与MnCl 2和[Li(NCN)] 2的摩尔比为2:1。在THF溶液中,2可能是离子物质[Li(THF)n ] [MnCl 2(NCN)](分子量测定和电导率测量),而磁测量表明存在高自旋d 5锰(II)中心。随后反应2用RLi得到[MnR(NCN)](R = Me(3a),n- Bu(3b))。使用CuCl作为助催化剂的配合物2是有效的催化剂体系,可用于格利雅试剂与烷基溴的交叉偶联以及有机卤化镁在α,β-不饱和酮上的1,4-加成反应。无需其他添加剂或助溶剂。与标准锰/铜系统相比,对于这两种反应,均观察到反应时间的显着减少。具有不饱和或杂原子官能团的烷基溴化物可以交叉偶联。另外,在1,4-加成反应中观察到对通常不反应的β,β-二取代的酮具有优异的反应性。