Work

Intermolecular 2 + 2 Carbonyl–Olefin Photocycloadditions Enabled by Cu(I)–Norbornene MLCT

Year: 2019

Type: article

Abstract: Photocycloadditions are often typified by the oxetane-forming Paternò-Büchi reaction. However, the mechanistic constraints of carbonyl excitation and olefin interception have limited this attractive oxetane-forming pathway. Here we describe the use of a Cu(I) precatalyst that achieves selective olefin activation via coordination to the metal center. Significantly, this intermolecular 2 + 2 carbonyl-olefin photocycloaddition engages alkyl ketones, which are more challenging to accommodate via direct irradiation pathways. Mechanistic investigations support the in situ formation of a Cu-norbornene resting state that undergoes a MLCT leading to oxetane formation.

Source: Journal of the American Chemical Society

DOI: 10.1021/jacs.9b03775

Authors: Daniel M. Flores, Valerie A. Schmidt

Institution: University of California San Diego

Language: English

Topic: Radical Photochemical Reactions

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: green

Funders: U.S. Department of Education, University of California, San Diego

Award: G485470145