双齿钌配合物(HO-C 5 H 3 N-CO-C 5 H 3 N-C 5 H 4 N)Ru(CO)2 Cl 2(2)可以转变为三齿产物(HO-C 5 H 3 N- CO-C 5 H 3 N-C 5 H 4 N)Ru(CO)Cl 2(3),其在PPh 3存在下进一步与CH 3 ONa反应,转化为两种络合物[(OC 5 H 3 N-CO- C 5高3NC 5 H 4 N)Ru(PPh 3)2(CO)] Cl –(4)和[(OC 5 H 3 N-CO-C 5 H 3 N-C 5 H 4 N)Ru(PPh 3)(CO) Cl](5),通过-OH去质子化。研究了仲醇与氨基醇的催化偶合环化反应,并且配合物3表现出最高的活性。偶联反应在空气中仅以0.2 mol%的催化剂负载量进行,并具有广泛的吡啶,喹诺酮和吡咯的合成范围。
Direct synthesis of pyridines and quinolines by coupling of γ-amino-alcohols with secondary alcohols liberating H2 catalyzed by ruthenium pincer complexes
A novel, one-step synthesis of substituted pyridine- and quinoline-derivatives was achieved by acceptorless dehydrogenativecoupling of gamma-aminoalcohols with secondaryalcohols. The reaction involves consecutive C-N and C-C bond formation, catalyzed by a bipyridyl-based rutheniumpincercomplex with a base.