Selective Synthesis of o-Acylbenzylphosphonates by Insertion Reactions of Arynes into β-Ketophosphonates

A mild method for selective synthesis of o-acylbenzylphosphonates has been developed by the reactions of arynes with beta-ketophosphonates. In the presence of CsF and THF, the carbon-carbon sigma-bonds of 2-oxopropylphosphonates were selectively cleaved and added to arynes providing the corresponding 2-acylbenzylphosphonates in moderate to good yields.