Rapid Access to Benzoxaphospholes and Their Spiro Analogues by a Three-Component Coupling Involving Arynes, Phosphines, and Activated Ketones

An operationally simple multicomponent coupling involving in situ generated arynes from 2-(tri­methyl­silyl)­aryl triflates, phosphines, and various acyclic and cyclic activated carbonyl compounds has been developed. The reaction proceeds via a formal [3 + 2] cycloaddition mode giving access to differently substituted (spiro)­benzoxa­phos­phole derivatives in moderate to good yields. Mild reaction conditions, a broad scope, and the possibility of varying all the three-components are the notable features of the present reaction.