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.