We discovered that highly regioselective H/D exchange can be achieved on the α-position of the pentafluorophenyl (Pfp) ester using Et₃N as the catalyst and D₂O as the deuterium source. Our computational and experimental results showed that the Pfp group can significantly increase the acidity of the α-hydrogen of the ester. This mild reaction condition tolerated a variety of functional groups. 90%∼98% yields and 91%∼98% deuterium incorporations were obtained with all the tested Pfp esters. Taking advantage of the high reactivity of Pfp esters, a series of valuable α-deuterio carboxylic acid derivatives, including herbicide, drugs and drug intermediates, have been synthesized using α-deuterio Pfp esters as precursors.

中文翻译：

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五氟苯基作为活化基团：通过 Et3N 催化 H/D 交换合成 α-氘代羧酸衍生物

我们发现，使用 Et ₃ N 作为催化剂和 D ₂ O 作为氘源，可以在五氟苯基 (Pfp) 酯的α位上实现高度区域选择性的 H/D 交换。我们的计算和实验结果表明，Pfp 基团可以显着增加酯的α-氢的酸度。这种温和的反应条件耐受多种官能团。用所有测试的 Pfp 酯获得了 90%~98% 的产率和 91%~98% 的氘掺入。利用Pfp酯的高反应活性，利用α合成了一系列有价值的α-氘代羧酸衍生物，包括除草剂、药物和药物中间体。-氘代Pfp酯作为前体。