Photochemical Synthesis of s-Triazolo[3,4-b]benzothiazole and Mechanistic Studies on Benzothiazole Formation
摘要:
A general photochemical synthesis of s-triazolo[3,4-b]benzothiazoles from 4,5-disubstituted 1,2,4-triazole-3-thione is described. Steady photolysis, quantum yield determination, and laser flash photolysis experiments have been carried out. An intramolecular electron transfer mechanism has been proposed.
Convenient synthesis of benzo[4,5]thiazolo[2,3-c][1,2,4]triazoles with 1 mol% CuCl<sub>2</sub>·2H<sub>2</sub>O as catalyst in water
作者:Li-Rong Wen、Shou-Lei Li、Jian Zhang、Ming Li
DOI:10.1039/c4gc02156h
日期:——
A convenient and efficient procedure for the synthesis of benzo[4,5]thiazolo [2,3-c][1,2,4]triazoles has been developed via a tandem intermolecular C–N bond and intramolecular C–S bond formation sequence from o-bromo-arylisothiocyanates and aroylhydrazides. A series of benzo[4,5]thiazolo[2,3-c][1,2,4]triazoles were provided in excellent overall yields with 1 mol% CuCl2·2H2O/1 mol% 1,10-phenanthroline
通过串联分子间C–N键和分子内CS键形成序列,开发了一种便捷高效的合成苯并[4,5]噻唑并[2,3- c ] [1,2,4]三唑的方法由邻-溴-芳基异硫氰酸酯和芳酰肼得到。以1 mol%CuCl 2 ·2H 2 O / 1 mol%1,10-菲咯啉提供了一系列优异的总收率的一系列苯并[4,5]噻唑并[2,3- c ] [1,2,4]三唑作为催化剂,水作为溶剂。
Study of Oxidative Cyclization Using PhI(OAc)2 in the Formation of Benzo[4,5]thiazolo[2,3-c][1,2,4]triazoles and Related Heterocycles – Scope and Limitations
the synthesis of benzo[4,5]thiazolo[2,3- c ][1,2,4]triazoles and related heterocycles under mild conditions was herein developed. The key step of this transformation is an oxidative cyclization employing PhI(OAc) 2 as reagent. Scope and limitations (group functionality tolerance and sterics) were studied showing the robustness of the present methodology which can be used as potential access to new fused
Thallium(III) Salts Mediated Oxidative Cyclization of Arenecarbaldehyde Benzothiazol-2-ylhydrazones to Bridged Head Nitrogen Heterocycles
作者:Om V. Singh、Varughese George
DOI:10.1080/00397919408010575
日期:1994.10
arenecarbaldehydebenzothiazol-2-ylhydrazones (4) with thallium (III) acetate in refluxing acetic acid, thallium (III) acetate and thallium (III) nitrate in acetonitrile in presence of p-toluene sulphonic acid afforded 3-aryl-1,2,4-triazolo[3,4-b]benzothiazoles (6) by intramolecular cyclization in high yield. A mechanistic scheme for this transformation has been proposed.