Palladium-catalyzed double-bond migration of unsaturated hydrocarbons accelerated by tantalum chloride
作者:Masahito Murai、Kengo Nishimura、Kazuhiko Takai
DOI:10.1039/c9cc00223e
日期:——
The operationally simple palladium-catalyzed double-bond migration without heteroatom-containing coordinating functional groups is described. Addition of TaCl5 as a second catalyst greatly enhanced the migration efficiency to provide β-alkylstyrenes through migration of up to a five-carbon chain. Both catalysts were commercially available, and the reaction occurred without external ligands under neutral
Pentafluorophenyl Group as Activating Group: Synthesis of α‐Deuterio Carboxylic Acid Derivatives via Et
<sub>3</sub>
N Catalyzed H/D Exchange
作者:Mengqi Peng、Hengzhao Li、Zixuan Qin、Junyu Li、Yanhao Sun、Xiaoxu Zhang、Ling Jiang、Hainam Do、Jie An
DOI:10.1002/adsc.202200258
日期:2022.7.5
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%
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。