Mechanisms and Synthetic Strategies in Visible Light‐Driven [2+2]‐Heterocycloadditions. Issue 8 (12th January 2023)

• Record Type: Journal Article
• Authors: Franceschi, Pietro; Cuadros, Sara; Goti, Giulio; Dell'Amico, Luca
• Is Part Of: Angewandte Chemie international edition. Volume 62:Issue 8(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-01-12
• Subjects: Cycloaddition -- Oxetane -- Photocatalysis -- Photochemistry -- Synthetic Methods; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.202217210
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The synthesis of four membered heterocycles usually requires multi‐step procedures and prefunctionalized reactants. A straightforward alternative is the photochemical [2+2]‐heterocycloaddition between an alkene and a carbonyl derivative, conventionally based on the photoexcitation of this latter. However, this approach is limited by the absorption profile of the carbonyl, requiring in most of the cases the use of high‐energy UV‐light, that often results in undesired side reactions and/or the degradation of the reaction components. The development of new and milder visible light‐driven [2+2]‐heterocycloadditions is, therefore, highly desirable. In this Review, we highlight the most relevant achievements in the development of [2+2]‐heterocycloadditions promoted by visible light, with a particular emphasis on the involved reaction mechanisms. The open challenges will also be discussed, suggesting new possible evolutions, and stimulating new methodological developments in the field. Abstract : The [2+2]‐heterocycloaddition between alkenes and carbonyls is a formidable strategy for the synthesis of complex strained 3D architectures. This Review provides an overview on the recent development of [2+2]‐heterocycloadditions driven by visible light. The diverse synthetic approaches are presented with special emphasis on the involved reaction mechanisms along with possible future directions of the field.