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Chromium photocatalysis: accessing structural complements to Diels-Alder adducts with electron-deficient dienophiles.

ABSTRACT: A chromium-catalyzed, visible light-activated net [4 + 2] cycloaddition between dienes and electron-deficient alkenes is described. Gathered evidence, via control experiments, isolated intermediates, and measured redox potentials, points to several converging reaction pathways that afford the cyclohexene adducts, including a photochemical [2 + 2] cycloaddition/vinylcyclobutane rearrangement cascade and a substrate excitation/oxidation sequence to a radical cation intermediate. Notably, the accompanying mechanistic stipulations result in a process that yields regioisomeric compounds from those generated by traditional Diels-Alder cycloadditions.

SUBMITTER: Stevenson SM

PROVIDER: S-EPMC5297334 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Chromium photocatalysis: accessing structural complements to Diels-Alder adducts with electron-deficient dienophiles.

Stevenson Susan M SM Higgins Robert F RF Shores Matthew P MP Ferreira Eric M EM

Chemical science 20160912 1

A chromium-catalyzed, visible light-activated net [4 + 2] cycloaddition between dienes and electron-deficient alkenes is described. Gathered evidence, <i>via</i> control experiments, isolated intermediates, and measured redox potentials, points to several converging reaction pathways that afford the cyclohexene adducts, including a photochemical [2 + 2] cycloaddition/vinylcyclobutane rearrangement cascade and a substrate excitation/oxidation sequence to a radical cation intermediate. Notably, th ...[more]

PMID: 28451213

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