Heterogeneous nickel-catalysed reversible, acceptorless dehydrogenation of N-heterocycles for hydrogen storage

Abstract

Nickel catalyst for hydrogen storage in N-heterocycles: a heterogeneous nickel catalyst promotes both hydrogenation and subsequent dehydrogenation of quinoline derivatives.

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

“…Some of them, including supported Pt, Pd, Rh, Co, Cu and Pd−Ni bimetallic nanoparticles encapsulated in MIL‐100(Fe), have been investigated in the acceptorless dehydrogenations (Scheme a) . Very recently, Beller and coworkers used intermetallic nickel silicide supported on fumed silica as catalyst to promote the acceptorless dehydrogenation of tetrahydroquinolines . For the aerobic dehydrogenation of N‐heterocycles (Scheme b), Pt, Au, Rh, Ru, Co, Fe‐based heterogeneous catalysts, mesoporous manganese oxide and Mn−Ni layered hydroxide, have been prepared.…”

“…[8] Very recently, Beller and coworkers used intermetallic nickel silicide supported on fumed silica as catalyst to promote the acceptorless dehydrogenation of tetrahydroquinolines. [9] For the aerobic dehydrogenation of N-heterocycles (Scheme 1b), Pt, Au, Rh, Ru, Co, Fe-based heterogeneous catalysts, [10] mesoporous manganese oxide [11] and MnÀ Ni layered hydroxide, [12] have been prepared. Besides, Gong's group reported the special graphene oxide as catalyst was successfully applied in this transformation.…”

“…As far as we know, heterogeneous catalyst solely based on nickel employed in this type of reaction was first reported by Beller's group. [9] However, this strategy still suffers from complex preparation of catalyst and need of high temperature. Hence, the development of nano-nickel catalysts with easy preparation, high stability and excellent catalytic activity for dehydrogenation of N-heterocycles under mild conditions is highly desirable in view of the principles of practical chemistry.…”

Understanding the mechanism of the competitive adsorption in 8-methylquinoline hydrogenation over a Ru catalyst

“…[4][5][6][7][8] Therefore, the role of reaction parameters in the selectivity of QLs hydrogenation is widely investigated for obtaining the required product. [9][10][11][12][13] Two hydrogenated intermediates, 1,2,3,4-4H-QL and 5,6,7,8-4H-QL, were generated along with the completely hydrogenated product, 10H-QL. It is found that the selectivity to 4H-QL or 10H-QL is affected dramatically by the catalysts and solvents used in QL hydrogenation.…”

A rare earth hydride supported ruthenium catalyst for the hydrogenation ofN-heterocycles: boosting the activityviaa new hydrogen transfer path and controlling the stereoselectivity

“…A rare earth hydride supported ruthenium catalyst for the hydrogenation of N-heterocycles: boosting the activity via a new hydrogen transfer path and controlling the stereoselectivity † Introduction N-Heterocycles have been attracting much attention because of their great versatility in many pharmaceuticals, alkaloids, agrochemicals, and ne chemicals. [1][2][3][4] Recently, liquid organic hydrogen carriers (LOHCs) have been proposed as convenient and safe candidates for hydrogen storage and N-heterocycles are very typical LOHCs for their high hydrogen capacities and relatively low operating temperatures. [5][6][7][8] One of the most wellstudied LOHCs is N-ethylcarbazole (NEC), whose hydrogen-rich state dodecahydro-N-ethylcarbazole (12H-NEC) is liquid at room temperature with a hydrogen capacity of 5.8 wt%.…”