Recent Advances in Photoinduced Oxidative Cleavage of Alkenes

Abstract

Oxidative cleavage of alkenes leading to valuable carbonyl derivatives is a fundamental transformation in synthetic chemistry. In particular, ozonolysis is the mainstream method for the oxidative cleavage of alkenes that has been widely implemented in the synthesis of natural products and pharmaceutically relevant compounds. However, due to the toxicity and explosive nature of ozone, alternative approaches employing transition metals and enzymes in the presence of oxygen and/or strong oxidants have been developed. These protocols are often conducted under harsh reaction conditions that limit the substrate scope. Photochemical approaches can provide milder and more practical alternatives for this synthetically useful transformation. In this review, we outline recent visible-light-promoted oxidative cleavage reactions that involve photocatalytic activation of oxygen via electron transfer and energy transfer. Also, an emerging field featuring visible-light-promoted oxidative cleavage under anaerobic conditions is discussed. The methods highlighted in this review represent a transformative step toward more sustainable and efficient strategies for the oxidative cleavage of alkenes.

Keywords: aerobic; alkenes; anaerobic; nitroarenes; oxidative cleavage; ozonolysis; photochemistry; visible light.

Scheme 1

(A) Mechanism of ozonolysis and (B) ozonolysis in the synthesis of complex bioactive molecules

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Mn-catalyzed, visible-light-driven alkene cleavage protocol (Xiao)

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Visible-light-promoted, transition-metal-catalyzed oxidative cleavage of styrenes under ambient atmosphere (Xie)

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Cadmium selenide quantum dots assisted photooxidative cleavage of alkenes under air (Meng)

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Diaryl disulfide catalyzed photooxidative alkene cleavage via a disulfide olefin complex formation (Wang)

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Rose Bengal catalyzed photooxidative alkene cleavage (Zhang)

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Visible-light-promoted aerobic oxidative alkene cleavage via charge transfer complex formation (Yang)

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Iodine-catalyzed photooxidative alkene cleavage (Itoh)

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CMP-assisted photooxidative cleavage of alkenes (Zhang)

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Solar energy promoted PCN catalyzed oxidative cleavage protocol (Das)

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(A) Ambient air oxidative cleavage protocol via photoactive pyridyl-containing substrates (Fu) and (B) Protocol for autooxidation promoted cleavage of alkenes (Zhang)

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Protocol for anaerobic oxidative cleavage of alkenes via photoinduced nitroarenes (Parasram)

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(A) Protocol for anaerobic oxidative cleavage of alkenes via photoinduced nitroarenes and (B) regioselectivity for competing C=C bonds (Leonori)