Cerium ammonium nitrate-catalyzed aerobic oxidative coupling of dithiocarbamates: facile synthesis of thioureas and bis(aminothiocarbonyl)disulfides
作者:Tian-Tian Li、Xiang-Hai Song、Mei-Shuang Wang、Ning Ma
DOI:10.1039/c4ra04628e
日期:——
Diverse disubstituted and trisubstituted thioureas were synthesized by the condensation of dithiocarbamate TEA (or DABCO) salts and amines using cerium ammonium nitrate (CAN) as a catalyst in high yields at room temperature. It is a one-pot method and it is unnecessary to isolate isothiocyanates. This reaction probably took place through nucleophilic addition of amines to isothiocyanates, which were generated by oxidative coupling of dithiocarbamates and the following decomposition of bis(aminothiocarbonyl)disulfides. When secondary amines and CS2 served as the reactants, bis(aminothiocarbonyl)disulfides were obtained via tandem nucleophilic addition/oxidative coupling reactions in moderate to excellent yields. In all the coupling reactions, the oxidant was air and CAN possibly acted as an SET catalyst.
Synthetic Studies toward Aryl-(4-aryl-4<i>H</i>-[1,2,4]triazole-3-yl)-amine from 1,3-Diarylthiourea as Urea Mimetics
作者:Amarnath Natarajan、Yuhong Guo、Haribabu Arthanari、Gerhard Wagner、Jose A. Halperin、Michael Chorev
DOI:10.1021/jo0508189
日期:2005.8.1
4]triazole-3-yl-amines as urea mimetics from the corresponding 1,3-disubstituted thioureas has been studied, and the scope and limitations of this reaction are presented. The reaction proceeds through the formation of a carbodiimide, followed by a sequential addition−dehydration with acyl hydrazides. 1,3-Branched dialkylthioureas result in the formation of the corresponding ureas. The electronic and steric
A New Synthetic Protocol for the Preparation of Carbodiimides Using a Hypervalent Iodine(III) Reagent
作者:Yunyang Wei、Chenjie Zhu、Dan Xu
DOI:10.1055/s-0030-1258414
日期:2011.3
A new, simple, and efficient preparation of symmetrical and unsymmetrical carbodiimides from the corresponding thioureas via dehydrosulfurization using a hypervalent iodine(III) reagent is described. The oxidation afforded carbodiimides in excellent yields and high selectivity. A possible mechanism for the transformation is proposed. desulfurization - hypervalent iodine - oxidations - carbodiimides
Nickel Catalysis Enables Access to Thiazolidines from Thioureas via Oxidative Double Isocyanide Insertion Reactions
作者:Wen-Kui Yuan、Yan Fang Liu、Zhenggang Lan、Li-Rong Wen、Ming Li
DOI:10.1021/acs.orglett.8b03098
日期:2018.11.16
Ni-catalyzed oxidative double isocyanide insertion to thioureas under air conditions, in which thioureas play three roles as a substrate, a ligand, and overcoming isocyanide polymerization. The reaction is featured by employing a low-cost and low loading Ni(acac)2 catalyst, without any additives, and high atom economy. This is the first example to directly apply a Ni(II) catalyst in oxidative double isocyanide
An efficient and mild oxidative desulfurization procedure using o-iodoxybenzoic acid has been developed for the synthesis of carbodiimides starting from easily synthesizable 1,3-disubstituted thioureas.