Work

Synthesis of Bicyclo[3.2.0]heptanes by Organophotoredox Catalytic Diastereoselective Anion Radical [2+2] Photocycloadditions of Arylenones under Batch and Flow Conditions

Year: 2024

Type: article

Abstract: In this study, the anion radical [2+2] photocycloaddition of aryl‐enones was investigated under batch and flow conditions. The reaction was promoted by LiBr as a Lewis acid and catalyzed by Eosin Y under visible light irradiation. Symmetrical enones and asymmetrical unsaturated ketoesters were effectively cyclized to yield substituted bicyclo[3.2.0]heptanes in high yield and diastereoselectivity. Through the exploration of different experimental setups and reaction conditions, a precise control over the diastereoselectivity of the process was achieved, favoring the formation of either cis or trans substituted bicyclo[3.2.0]heptanes. In‐flow experiments allowed to further improve the efficiency of the methodology, leading to higher productivity and space time yields. Furthermore, DFT investigations were conducted in order to elucidate the reaction mechanism.

Source: European Journal of Organic Chemistry

DOI: 10.1002/ejoc.202400816

Authors: Tommaso Benettin, Simonetta Resta, Alessandra Puglisi, Sergio Rossi

Institution: University of Milan

Language: English

Topic: Radical Photochemical Reactions

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,330

Funders: Università degli Studi di Milano, European Commission, Papua New Guinea University of Technology