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Visible Light Photocatalysis of 6? Heterocyclization.

ABSTRACT: Photo-mediated 6? cyclization is a valuable method for the formation of fused heterocyclic systems. Here we demonstrate that irradiation of cyclic 2-aryloxyketones with blue LED light in the presence of an IrIII complex leads to efficient and high yielding arylation across a panoply of substrates by energy transfer. 2-Arylthioketones and 2-arylaminoketones also cyclize effectively under these conditions. Quantum calculation demonstrates that the reaction proceeds via conrotatory ring closure in the triplet excited state. Subsequent suprafacial 1,4-hydrogen shift and epimerization leads to the observed cis-fused products.

SUBMITTER: Munster N

PROVIDER: S-EPMC5575533 | biostudies-other | 2017 Aug

REPOSITORIES: biostudies-other

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Visible Light Photocatalysis of 6π Heterocyclization.

Münster Niels N Parker Nicholas A NA van Dijk Lucy L Paton Robert S RS Smith Martin D MD

Angewandte Chemie (International ed. in English) 20170704 32

Photo-mediated 6π cyclization is a valuable method for the formation of fused heterocyclic systems. Here we demonstrate that irradiation of cyclic 2-aryloxyketones with blue LED light in the presence of an Ir<sup>III</sup> complex leads to efficient and high yielding arylation across a panoply of substrates by energy transfer. 2-Arylthioketones and 2-arylaminoketones also cyclize effectively under these conditions. Quantum calculation demonstrates that the reaction proceeds via conrotatory ring ...[more]

PMID: 28640479

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