Rapid access to benzoxaphospholes and their spiro analogues by a three-component coupling involving arynes,
Anup Bhunia1, Tony Roy, Rajesh G Gonnade
1Organic Chemistry Division, ‡Centre for Materials Characterization, CSIR-National Chemical Laboratory (CSIR-NCL) , Dr. Homi Bhabha Road, Pune - 411008, India.
Abstract:
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.
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