69404-95-1Relevant articles and documents
Copper-catalyzed formal transfer hydrogenation/deuteration of aryl alkynes
Sloane, Samantha E.,Reyes, Albert,Vang, Zoua Pa,Li, Lingzi,Behlow, Kiera T.,Clark, Joseph R.
, p. 9139 - 9144 (2020/11/30)
A copper-catalyzed reduction of alkynes to alkanes and deuterated alkanes is described under transfer hydrogenation and transfer deuteration conditions. Commercially available alcohols and silanes are used interchangeably with their deuterated analogues as the hydrogen or deuterium sources. Transfer deuteration of terminal and internal aryl alkynes occurs with high levels of deuterium incorporation. Alkyne-containing complex natural product analogues undergo transfer hydrogenation and transfer deuteration selectively, in high yield. Mechanistic experiments support the reaction occurring through a cis-alkene intermediate and demonstrate the possibility for a regioselective alkyne transfer hydrodeuteration reaction.
Development of Carbon-Neutral Cellulose-Supported Heterogeneous Palladium Catalysts for Chemoselective Hydrogenation
Yamada, Tsuyoshi,Teranishi, Wataru,Park, Kwihwan,Jiang, Jing,Tachikawa, Takumu,Furusato, Shinichi,Sajiki, Hironao
, p. 4052 - 4058 (2020/07/13)
Palladium catalysts immobilized on cellulose particles (Pd/CLP) and on a cellulose-monolith (Pd/CLM) were developed. These composites were applied as hydrogenation catalysts and their catalyst activities were evaluated. Although both catalysts catalyzed the deprotection of benzyloxycarbonyl-protected aromatic amines (Ar-N-Cbz) and aromatic benzyl esters (Ar-CO2Bn), only Pd/CLM could accomplish the hydrogenolysis of aliphatic-N-Cbz and aliphatic-CO2Bn protective groups. The difference in the physical structure of the cellulose supports induced unique chemoselectivity. Aliphatic-N-Cbz and aliphatic-CO2Bn groups were tolerated under the Pd/CLP-catalyzed hydrogenation conditions, while Ar-N-Cbz, Ar-CO2Bn, alkene, alkyne, azido and nitro groups could be smoothly reduced.
Generalized Chemoselective Transfer Hydrogenation/Hydrodeuteration
Wang, Yong,Cao, Xinyi,Zhao, Leyao,Pi, Chao,Ji, Jingfei,Cui, Xiuling,Wu, Yangjie
supporting information, p. 4119 - 4129 (2020/08/10)
A generalized, simple and efficient transfer hydrogenation of unsaturated bonds has been developed using HBPin and various proton reagents as hydrogen sources. The substrates, including alkenes, alkynes, aromatic heterocycles, aldehydes, ketones, imines, azo, nitro, epoxy and nitrile compounds, are all applied to this catalytic system. Various groups, which cannot survive under the Pd/C/H2 combination, are tolerated. The activity of the reactants was studied and the trends are as follows: styrene'diphenylmethanimine'benzaldehyde'azobenzene'nitrobenzene'quinoline'acetophenone'benzonitrile. Substrates bearing two or more different unsaturated bonds were also investigated and transfer hydrogenation occurred with excellent chemoselectivity. Nano-palladium catalyst in situ generated from Pd(OAc)2 and HBPin extremely improved the TH efficiency. Furthermore, chemoselective anti-Markovnikov hydrodeuteration of terminal aromatic olefins was achieved using D2O and HBPin via in situ HD generation and discrimination. (Figure presented.).
