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Photocatalytic reverse polarity Povarov reaction.

ABSTRACT: A visible light mediated iridium photocatalysed reverse polarity Povarov reaction of aryl imines and electron deficient alkenes is described. Operating via a putative nucleophilic ?-amino radical, generated by a proton coupled electron transfer process, addition to a range of conjugated electron deficient alkene substrates affords substituted tetrahydroquinoline products in high yields and with typically good to excellent diastereoselectivity in favor of the trans diastereoisomer. Sub-stoichiometric quantities of Hantzsch ester were found to be key to initiate the overall redox-neutral, free radical cyclization cascade. This new reaction complements existing two electron Lewis acid mediated variants and expands the capabilities of imine umpolung chemistry to synthetically relevant cyclisation methodology.

SUBMITTER: Leitch JA

PROVIDER: S-EPMC6115624 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Photocatalytic reverse polarity Povarov reaction.

Leitch Jamie A JA Fuentes de Arriba Angel L AL Tan Joanne J Hoff Oskar O Martínez Carlos M CM Dixon Darren J DJ

Chemical science 20180706 32

A visible light mediated iridium photocatalysed reverse polarity Povarov reaction of aryl imines and electron deficient alkenes is described. Operating via a putative nucleophilic α-amino radical, generated by a proton coupled electron transfer process, addition to a range of conjugated electron deficient alkene substrates affords substituted tetrahydroquinoline products in high yields and with typically good to excellent diastereoselectivity in favor of the trans diastereoisomer. ...[more]

PMID: 30310598

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