Catalytic C-C bond activation in biphenylene and cyclotrimerization of alkynes:: Increased reactivity of P,N- versus P,P-substituted nickel complexes
Catalytic C-C bond activation in biphenylene and cyclotrimerization of alkynes:: Increased reactivity of P,N- versus P,P-substituted nickel complexes
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DOI：
10.1021/om0110989
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发表时间：
2002-04-29
期刊：
影响因子：
2.8
通讯作者：
Jones, WD
中科院分区：
文献类型：
--
作者：
Müller, C;Lachicotte, RJ;Jones, WD
Ni(COD)(2) 与二齿杂化配体 (Pr-i)(2)CH2CH2NMe2 (PN) 和 PhCdropCR (R = Ph, Bu-t, CF3, C=CPh) 反应得到供体稳定的单核 Ni(0) 配合物 (PN)Ni(eta(2)-PhCdropCR) (R = Ph (1), Bu-t (4), 分别为CF3(5))和双核化合物(PN)Ni(eta(2);eta(2)-PhCdropC-CdropCPh)Ni(PN)(3)。在过量炔烃存在下，化合物 1、3 和 4 被证明是催化亚联苯中碳-碳键活化和形成相应 9,10-二取代菲的活性物质。然而，在过量CF3C=CPh和联亚苯基存在下，配合物5发生环三聚成苯衍生物而不是C-C键断裂。相比之下，相应的双膦基取代物质 (dippe)Ni(eta(2)-PhCetadropCR) (R = Ph (2), CF3 (9)) 显示出对菲形成或环三聚反应的催化活性显着降低。
Reaction of Ni(COD)(2) with the bidentate hybrid ligand (Pr-i)(2)CH2CH2NMe2 (PN) and PhCdropCR (R = Ph, Bu-t, CF3, C=CPh) afforded the donor-stabilized mononuclear Ni(0) complexes (PN)Ni(eta(2)-PhCdropCR) (R = Ph (1), Bu-t (4), CF3 (5)) and the dinuclear compound (PN)Ni(eta(2);eta(2)-PhCdropC-CdropCPh)Ni(PN) (3), respectively. In the presence of excess alkyne, compounds 1, 3, and 4 turned out to be active species for the catalytic carbon-carbon bond activation in biphenylene and formation of the corresponding 9,10-disubstituted phenanthrenes. However, cyclotrimerization to benzene derivatives instead of C-C bond cleavage occurred with complex 5 in the presence of excess CF3C=CPh and biphenylene. In contrast, the corresponding bis-phosphino-substituted species (dippe)Ni(eta(2)-PhCetadropCR) (R = Ph (2), CF3 (9)) showed substantially reduced catalytic activity toward phenanthrene formation or cyclotrimerization reactions.