Recent Advances in Photoinduced Oxidative Cleavage of Alkenes

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 visiblelight- 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. 1 Introduction 2 Photochemical Methods for Oxidative Cleavage of Alkenes under Aerobic Conditions 2.1 Transition-Metal-Catalyzed Oxidative Cleavage of Alkenes under Visible Light 2.2 Photopromoted Organocatalyzed Oxidative Cleavage of Alkenes 2.3 Oxidative Cleavage of Alkenes with Molecular Iodine under Visible Light 2.4 Polymer-Catalyzed Oxidative Cleavage under Visible Light Irradiation 2.5 Oxidative Cleavage via Direct Visible Light Excitation with Molecular Oxygen 3 Anaerobic Oxidative Cleavage of Alkenes under Visible Light 4 Conclusion.