ortho-Difunctionalization of arynes by LiZnEt2(TMP)-mediated deprotonative zincation/elimination of aryl triflates

Generation of arynes from aryl triflates has been achieved using lithium diethyl(tetramethylpiperidyl)-zincate base LiZnEt2(TMP), via a directed ortho-deprotonative zincation and subsequent elimination of the triflate group. The aryne formation has been demonstrated by the cycloaddition reaction with diene and insertion reactions with ureas. Furthermore, the nucleophilic addition of LiZnEt2(TMP) to arynes was observed in the absence of external aryne partners, offering a new cascade strategy for diverse difunctionalization of arynes. (C) 2018 Elsevier Ltd. All rights reserved.