Enhancing the selectivity of imines for the oxidative self-coupling of primary amines was found to be challenging in the heterogeneous catalysis.Three different manganese oxides(M-3,M-4,M-5) were synthesized by contro...Enhancing the selectivity of imines for the oxidative self-coupling of primary amines was found to be challenging in the heterogeneous catalysis.Three different manganese oxides(M-3,M-4,M-5) were synthesized by controlling the calcination temperature using a simple template-free oxalate route.The prepared manganese oxides were systematically characterized using XRD,N2 sorption,SEM,TEM,XPS,H2-TPR techniques.M-4 gave 96.2% selectivity of imine at 100% conversion of benzylamine,which was far more superior than other existing protocols.Mn^3+/Mn^4+ ratio was found to affect the selectivity of the imines.The probable reaction pathway for amines oxidation catalyzed by manganese oxides was proposed for the first time.展开更多
基金Financial support from the National Natural Science Foundation of China (NSFC,Nos.21776258,21476207,91534113,21406199, 21566013,21875220)Program from Science and Technology Department of Zhejiang Province (Nos.2015C31042, LY17B060006)+1 种基金Education Science Planning Project of Jiangxi Province (No.18YB243)Natural Science Foundation of Jiangxi Province (No.20181BAB216032)
文摘Enhancing the selectivity of imines for the oxidative self-coupling of primary amines was found to be challenging in the heterogeneous catalysis.Three different manganese oxides(M-3,M-4,M-5) were synthesized by controlling the calcination temperature using a simple template-free oxalate route.The prepared manganese oxides were systematically characterized using XRD,N2 sorption,SEM,TEM,XPS,H2-TPR techniques.M-4 gave 96.2% selectivity of imine at 100% conversion of benzylamine,which was far more superior than other existing protocols.Mn^3+/Mn^4+ ratio was found to affect the selectivity of the imines.The probable reaction pathway for amines oxidation catalyzed by manganese oxides was proposed for the first time.