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Towards a general ruthenium-catalyzed hydrogenation of secondary and tertiary amides to amines.

ABSTRACT: A broad range of secondary and tertiary amides has been hydrogenated to the corresponding amines under mild conditions using an in situ catalyst generated by combining [Ru(acac)₃], 1,1,1-tris(diphenylphosphinomethyl)ethane (Triphos) and Yb(OTf)₃. The presence of the metal triflate allows to mitigate reaction conditions compared to previous reports thus improving yields and selectivities in the desired amines. The excellent isolated yields of two scale-up experiments corroborate the feasibility of the reaction protocol. Control experiments indicate that, after the initial reduction of the amide carbonyl group, the reaction proceeds through the reductive amination of the alcohol with the amine arising from collapse of the intermediate hemiaminal.

SUBMITTER: Cabrero-Antonino JR

PROVIDER: S-EPMC6006866 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Towards a general ruthenium-catalyzed hydrogenation of secondary and tertiary amides to amines.

Cabrero-Antonino Jose R JR Alberico Elisabetta E Junge Kathrin K Junge Henrik H Beller Matthias M

Chemical science 20160209 5

A broad range of secondary and tertiary amides has been hydrogenated to the corresponding amines under mild conditions using an in situ catalyst generated by combining [Ru(acac)3], 1,1,1-tris(diphenylphosphinomethyl)ethane (Triphos) and Yb(OTf)3. The presence of the metal triflate allows to mitigate reaction conditions compared to previous reports thus improving yields and selectivities in the desired amines. The excellent isolated yields of two scale-up experiments ...[more]

PMID: 29997838

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