Nanonickel Oxides Prepared by Atomic Layer Deposition as Efficient Catalyst for the Dehydrogenation of N‐Heterocycles

Abstract

An efficient heterogeneous catalyst nickel oxide supported on graphene nanoplatelets (NiO/Gr) has been developed for the aerobic and additive-free dehydrogenation of N-heterocycles. This catalyst was easily prepared by atomic layer deposition from nickel(II) diketonate-diamine and ozone, which has advantages of excellent activity, low metal loading, simple preparation, stability for multiple reuse. The reactions proceed in good yields with broad substrate scope under mild conditions by using tiny quantity of catalyst. Interestingly, pharmaceutically relevant tetrahydro-β-carboline derivative can also be oxidized successfully to afford the important intermediate. The control experiments suggest that this catalytic dehydrogenation experiences radical-type oxidation.

Aerobic and Additive‐free Oxidative Dehydrogenation of N‐heterocycles over Commercial MnCO3‐derived Manganese Oxides

“…Heterogeneous Rh [5,6] , Pd [7,8] , Pt [9,10] , Au [11] catalysts can overcome the recycling issues, and accomplish the reactions with high activity, but the cost of the noble‐metals is very high. Consequently, there is a great interest in finding high active heterogeneous non‐noble‐metal catalysts as they can solve both the recycling and the cost problems [12–18] . For example, the heterogeneous iron‐nitrogen‐doped graphene (FeO x /NGr‐C) prepared by Beller et al.…”

Co-N-Si/AC Catalyst for Aerobic Oxidation of Benzyl Alcohols to Esters under Mild Conditions

“…Therefore, the exploration and development of efficient catalytic systems for oxidative esterification under mild conditions are of increasing interest in both green chemistry and organic synthesis. Continuous effort has gone into research in the conversion of plentiful and sustainable alcohol resources into functional molecules [23][24][25][26][27][28] and the exploitation of heterogeneous base metal catalysts as well as the catalytical oxidant performance of related heterogeneous catalysts [29][30][31][32][33]. The natural amplitude of cobalt and its excellent performance in the oxidation reaction [34][35][36] as well as the capacity of silicon dioxide in regulating the micropore size of carbon material to facilitate mass transfer have been observed [37][38][39].…”

An elegant and efficient synthesis of heterocycles integrated with bis‐N‐acyl pyrazoline and bis‐1, 2, 3‐triazole via a green synthetic methodology

“…Nitrogen containing heterocycles play a pivotal role in drug designing and development [1][2][3]. Amidst, pyrazolines are considered as privileged candidates due to their existence in numerous biologically active natural products and synthetic pharmaceuticals [4,5].…”