Assembly of 2-Arylbenzothiazoles through Three-Component Oxidative Annulation under Transition-Metal-Free Conditions
摘要:
Highly efficient methods for the synthesis of 2-arylbenzothiazoles and 2-arylnaphtho[2,1-d]thiazoles have been developed. Readily available aromatic amines, benzaldehydes, and elemental sulfur were directly assembled through oxidative annulation and C-H functionalization under transition-metal-free conditions, where DMSO or oxygen served as the oxidant. NH4I or KI as the catalyst was found to be effective to promote the transformations to give the annulation products in good to excellent yields with wide functional group tolerance.
NH<sub>4</sub>I-promoted oxidative formation of benzothiazoles and thiazoles from arylacetic acids and phenylalanines with elemental sulfur
作者:Yujia Xia、Huawen Huang、Wei Hu、Guo-Jun Deng
DOI:10.1039/d1ob00671a
日期:——
NH4I/K3PO4-based catalytic system has been established to enable oxidative formation of thiazole compounds from arylacetic acids and phenylalanines with elemental sulfur. While the three-component reaction of anilines or β-naphthylamines with arylacetic acids and elemental sulfur affords benzo[2,1-d]thiazoles and naphtho[2,1-d]thiazoles, the annulation of phenylalanines with elemental sulfur produces 2-benzyl
已经建立了基于NH 4 I/K 3 PO 4的催化体系,以使得能够从芳基乙酸和苯丙氨酸与元素硫氧化形成噻唑化合物。虽然苯胺或 β-萘胺与芳基乙酸和元素硫的三组分反应产生苯并[ 2,1- d ]噻唑和萘并[ 2,1- d ]噻唑,但苯丙氨酸与元素硫的环化产生 2-苄基和 2-苯甲酰基噻唑。这项工作很好地补充了以前来自其他偶联伙伴的苯并噻唑的三组分环化。
Assembly of 2-Arylbenzothiazoles through Three-Component Oxidative Annulation under Transition-Metal-Free Conditions
作者:Xingzong Che、Jingjing Jiang、Fuhong Xiao、Huawen Huang、Guo-Jun Deng
DOI:10.1021/acs.orglett.7b02168
日期:2017.9.1
Highly efficient methods for the synthesis of 2-arylbenzothiazoles and 2-arylnaphtho[2,1-d]thiazoles have been developed. Readily available aromatic amines, benzaldehydes, and elemental sulfur were directly assembled through oxidative annulation and C-H functionalization under transition-metal-free conditions, where DMSO or oxygen served as the oxidant. NH4I or KI as the catalyst was found to be effective to promote the transformations to give the annulation products in good to excellent yields with wide functional group tolerance.