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HMPA-Catalyzed Transfer Hydrogenation of 3-Carbonyl Pyridines and Other N-Heteroarenes with Trichlorosilane.

ABSTRACT: A method for the HMPA (hexamethylphosphoric triamide)-catalyzed metal-free transfer hydrogenation of pyridines has been developed. The functional group tolerance of the existing reaction conditions provides easy access to various piperidines with ester or ketone groups at the C-3 site. The suitability of this method for the reduction of other N-heteroarenes has also been demonstrated. Thirty-three examples of different substrates have been reduced to designed products with 45⁻96% yields.

SUBMITTER: Fu Y

PROVIDER: S-EPMC6384841 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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HMPA-Catalyzed Transfer Hydrogenation of 3-Carbonyl Pyridines and Other N-Heteroarenes with Trichlorosilane.

Fu Yun Y Sun Jian J

Molecules (Basel, Switzerland) 20190122 3

A method for the HMPA (hexamethylphosphoric triamide)-catalyzed metal-free transfer hydrogenation of pyridines has been developed. The functional group tolerance of the existing reaction conditions provides easy access to various piperidines with ester or ketone groups at the C-3 site. The suitability of this method for the reduction of other <i>N</i>-heteroarenes has also been demonstrated. Thirty-three examples of different substrates have been reduced to designed products with 45⁻96% yields. ...[more]

PMID: 30678314

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