Decatungstate-photocatalyzed transfer hydrogenation of unsaturated compounds using alcohol as the hydrogen source
Teng Zhang1, Zheng-Feng Zhang2, Xuan Lan3
1School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore, Singapore.
Abstract:
We present a simple and efficient photocatalytic method for the transfer hydrogenation of unsaturated compounds using alcohol as the hydrogen source and low-cost decatungstate as the photocatalyst. Our approach operates under mild and ambient conditions and demonstrates broad substrate compatibility, including alkyl, aryl, and heteroatom-substituted alkenes, alkynes, azo compounds and nitroarenes. To our knowledge, this study represents the first instance of using tungsten-based catalysts for the photocatalytic transfer hydrogenation of unsaturated compounds. Notably, the catalytic system, employing decatungstate as the catalyst and alcohol as the hydrogen source, exhibits high chemoselectivity, enabling selective hydrogenation of alkenes and alkynes even in the presence of reactive groups like ketones and carboxylic acids. These features highlight the considerable potential of this approach for practical and sustainable applications in organic synthesis.
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