Rh(III)-Catalyzed Three-Component <i>Syn</i> -Carboamination of Alkenes Using Arylboronic Acids and Dioxazolones

Abstract

Herein we report a Rh(III)-catalyzed three-component carboamination of alkenes from readily available aryl boronic acids as a carbon source and dioxazolones as nitrogen electrophiles. This protocol provides facile access to valuable amine products including <i>α</i>-amino acid derivatives in good yield and regioselectivity without the need for a directing functionality. A series of experiments suggest a mechanism in which the Rh(III) catalyst undergoes transmetalation with the aryl boronic acid followed by turnover limiting, alkene migratory insertion into the Rh(III)-aryl bond. Subsequently, fast Rh-nitrene formation provides the <i>syn</i>-carboamination product selectively after reductive elimination and proto-demetalation. Importantly, the protocol provides 3-component coupling products in preference to a variety of 2-component undesired by-products.