Copper-catalyzed [2+3]-annulation of N–H imines with vinyl azides: access to polyaryl 2<i>H</i>-imidazoles
作者:Zhongzhi Zhu、Hanze Lin、Baihui Liang、Junjie Huang、Wanyi Liang、Lu Chen、Yubing Huang、Xiuwen Chen、Yibiao Li
DOI:10.1039/c9cc10042c
日期:——
A practical method for the synthesis of 2H-imidazoles via a [2+3] annulation of N-H imines with vinylazides using a copper catalyst is developed. In this conversion, environmentally friendly oxygen is used as the sole oxidant and N2 and H2O are the only by-products. The catalytic transformation, operating under mild conditions, is operationally simple and is considered as a readily available catalytic
Electrocatalytic Synthesis of gem-Bisarylthio Enamines and α-Phenylthio Ketones via a Radical Process under Mild Conditions
作者:Xiu-Jin Meng、Zu-Yu Mo、Yong-Zhou Pan、Shi-Yan Cheng、Qian-Yu Li、Hai-Tao Tang、Ying-Ming Pan
DOI:10.1055/a-1335-7902
日期:2021.4
The novel method for the synthesis of gem-bisarylthio enamines and α-phenylthio ketones was developed via the coupling of α-substituted vinyl azides with thiols in the presence of tetrabutylammonium iodide (TBAI) as a redox catalyst and electrolyte at room temperature. Electronic properties were crucial in the generated products. This protocol features metal- and oxidant-free materials, broad tolerance
AgN<sub>3</sub>-Catalyzed Hydroazidation of Terminal Alkynes and Mechanistic Studies
作者:Shanshan Cao、Qinghe Ji、Huaizhi Li、Maolin Pang、Haiyan Yuan、Jingping Zhang、Xihe Bi
DOI:10.1021/jacs.0c00836
日期:2020.4.15
hydroazidation of alkynes is the most straightforward way to access vinyl azides - versatile building blocks in organic synthesis. We previously realized such a fundamental reaction of terminalalkynes using Ag2CO3 as a catalyst. However, the high catalyst loading seriously limits its practicality, and moreover the exact reaction mechanism remains unclear. Here, on the basis of X-ray diffraction studies on the
Synthesis of β-Difluoroalkyl Azides via Elusive 1,2-Azide Migration
作者:Yongquan Ning、Paramasivam Sivaguru、Giuseppe Zanoni、Edward A. Anderson、Xihe Bi
DOI:10.1016/j.chempr.2019.12.004
日期:2020.2
development of azide migration reactions is a formidable challenge because of the potential competition of side processes driven by the release of molecular nitrogen. Here, we report a conceptually novel 1,2-azide migration in an unprecedented gem-difluorination of the readily available α-vinyl azides, a transformation that enables the synthesis of a range of novel β-difluorinated alkyl azides. The practicality
Transformation of Alkynes into α- or β-Difluorinated Alkyl Azides by an Efficient One-Pot Two-Step Procedure
作者:Huaizhi Li、Bhoomireddy Rajendra Prasad Reddy、Xihe Bi
DOI:10.1021/acs.orglett.9b03593
日期:2019.12.6
herein an unprecedented 1,2-azide migratory hydroazidation and subsequent gem-difluorination of alkynes accessing β-difluorinated alkylazides. Importantly, functional group controlled 1,2-azide or 1,2-aryl migration was observed in the case of aromatic alkynes. Moreover, the azide group is sustained up to the final product. The method can be easily adapted for large-scale preparation, and the resulting