论文部分内容阅读
Two new phosphine-free Ru(Ⅱ)-NNN pincer complexes([RuCl(L1)(CH3CN)2]Cl(1)and [RuCl(L2)(CH3CN)2]Cl(2),L1 = 2,6-bis(1H-imidazole-2-yl)pyridine,L2 = 2,6-bis(1-hexyl-1H-imidazole-2-yl)-pyridine)were synthesized for homogeneously catalyzing the condensation of benzyl alcohol and benzene-1,2-diamine to 2-pheny-1H-benzo[d]imidazole and H2.It was found that the reactivity with an order of 1> 2 is lower than that of the phosphine-containing Ru(Ⅱ)-NNN pincer complex [RuCl2(L1)(PPh3)3](3),and thus a homogeneous system containing complex 1,1 equiv.of 1,2-bis(diphenyl-phosphanyl)ethane(dppe),and 10 equiv.of NaBPh4 was developed to improve the catalytic efficiency for the condensation of primary alcohols and benzene-1,2-diamine(or its derivatives)to 2-substituted 1H-benzo[d]imidazoles in excellent yields(up to 97%)and turnover number(TONs~388).