钯（II）催化的芳基脲 C-H 直接芳基化反应中的芳香性依赖区域选择性。

Aromaticity-Dependent Regioselectivity in Pd(II)-Catalyzed C-H Direct Arylation of Aryl Ureas.

机构信息

International Joint Research Laboratory of Nano-Micro Architecture Chemistry (NMAC), Department of Organic Chemistry, College of Chemistry, Jilin University , 2699 Qianjin Street, Changchun 130012, P. R. China.

出版信息

Org Lett. 2015 Dec 4;17(23):5918-21. doi: 10.1021/acs.orglett.5b03153. Epub 2015 Nov 17.

DOI:10.1021/acs.orglett.5b03153

PMID:26575848

Abstract

Palladium-catalyzed C-H direct arylation generally occurs on the ortho-position of directing groups. By comparing meta-arylated products of 2-naphthyl urea to ortho-arylated products of phenyl urea, the ortho- and meta-regioselectivity of aryl ureas were found to depend on the aromaticity of the corresponding aryl substituents. Thus, aromaticity is a new factor which can affect the regioselectivity in C-H direct arylation. The finding was further confirmed by regioselective direct arylation of indole and pyrrole derivatives.

摘要

钯催化的 C-H 直接芳基化通常发生在导向基团的邻位。通过比较 2-萘基脲的间位芳基化产物和苯基脲的邻位芳基化产物，发现芳基脲的邻位和间位选择性取决于相应芳基取代基的芳香性。因此，芳香性是一个新的因素，可以影响 C-H 直接芳基化的区域选择性。这一发现通过吲哚和吡咯衍生物的区域选择性直接芳基化进一步得到了证实。