2-Amino-5,6-difluorophenyl-1<i>H</i>-pyrazole-Directed Pd<sup>II</sup> Catalysis: Arylation of Unactivated β-C(sp<sup>3</sup>)–H Bonds
作者:Jinyue Yang、Xiaopan Fu、Shibiao Tang、Kezuan Deng、Lili Zhang、Xianjin Yang、Yafei Ji
DOI:10.1021/acs.joc.9b01276
日期:2019.8.16
efficient and readily removable directing group. Two fluoro groups are installed at the 5- and 6-position of the anilino moiety in 2-aminophenyl-1H-pyrazole, clearly enhancing the directing ability of the auxiliary. In addition, the protocol employs Cu(OAc)2/Ag3PO4 (1.2/0.3) as additives, evidently reducing the stoichiometric amount of expensive silver salts. Furthermore, this process exhibits high β-site
首次描述了使用2-氨基-5,6-二氟苯基-1 H-吡唑作为有效且易于去除的钯衍生物催化羧酸衍生物中未活化的β-C(sp 3)–H键与芳基碘化物的芳基化指导小组。在2-氨基苯基-1 H-吡唑的苯胺基部分的5-位和6-位安装了两个氟基团,明显增强了辅助剂的导向能力。此外,该协议使用Cu(OAc)2 / Ag 3 PO 4(1.2 / 0.3)作为添加剂,明显减少了昂贵的银盐的化学计量。此外,该方法显示出高的β-位点选择性,与含有α-氢原子的各种底物的相容性以及优异的官能团耐受性。