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Orthogonal Syntheses of 3.2.0 Bicycles from Enallenes Promoted by Visible Light.

ABSTRACT: Enallenes can be readily converted into two families of 3.2.0 (hetero)bicycles with high diastereoselectivities through the combination of visible light with a suitable Ir(III) complex (1 mol %). Two complementary pathways, namely, a photocycloaddition versus a radical chain, can then take place. Both manifolds grant complete regiocontrol of the allene difunctionalization. This is accompanied by an original 1,3-group shift using sulfonyl allenamides that deliver a congested tetrasubstituted headbridging carbon in the corresponding product.

SUBMITTER: Serafino A

PROVIDER: S-EPMC8010793 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Orthogonal Syntheses of 3.2.0 Bicycles from Enallenes Promoted by Visible Light.

Serafino Andrea A Balestri Davide D Marchiò Luciano L Malacria Max M Derat Etienne E Maestri Giovanni G

Organic letters 20200805 16

Enallenes can be readily converted into two families of 3.2.0 (hetero)bicycles with high diastereoselectivities through the combination of visible light with a suitable Ir(III) complex (1 mol %). Two complementary pathways, namely, a photocycloaddition versus a radical chain, can then take place. Both manifolds grant complete regiocontrol of the allene difunctionalization. This is accompanied by an original 1,3-group shift using sulfonyl allenamides that deliver a congested tetrasubstituted head ...[more]

PMID: 32806183

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