A facile and versatile method for the preparation of cyanoguanidines 7 from amines 3 and isothiocyanates 4 via a methylation, cyanamide-treatment sequence is described.
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.
申请人:DOW GLOBAL TECHNOLOGIES LLC 다우 글로벌 테크놀로지스 엘엘씨(520020158236)
公开号:KR20190060809A
公开(公告)日:2019-06-03
본 구현예는 화학식 I의 포스파구아니딘 금속 착체 및 a-올레핀 중합 시스템에서의 이들 착체의 이용에 관한 것이다.
本实施例涉及化学式I的钴基磷钼酸镍金属配合物及其在α-氧化酶聚合系统中的使用。
Gram Scalable Method to Synthesize Biscarbodiimides and Asymmetric Monocarbodiimides: A Platform to Access an Array of Phosphaguanidines, Amidines, and Guanidines
作者:Andrew M. Camelio、Arkady Krasovskiy、Brad Bailey、Anna Davis
DOI:10.1021/acs.joc.1c01281
日期:2022.2.18
variety of mono- and bis-carbodiimides in good yield and high purity on multigram scale. Direct addition into these versatile motifs facilitated the rapid synthesis of a library of novel amidinines, guanidines, and phosphaguandines.
Continuous-Flow Synthesis of Thioureas, Enabled by Aqueous Polysulfide Solution
作者:András Gy. Németh、Renáta Szabó、György Orsy、István M. Mándity、György M. Keserű、Péter Ábrányi-Balogh
DOI:10.3390/molecules26020303
日期:——
We have developed the continuous-flow synthesis of thioureas in a multicomponent reaction starting from isocyanides, amidines, or amines and sulfur. The aqueous polysulfide solution enabled the application of sulfur under homogeneous and mild conditions. The crystallized products were isolated by simple filtration after the removal of the co-solvent, and the sulfur retained in the mother liquid. Presenting
1-(Methyldithiocarbonyl)imidazole: a Useful Thiocarbonyl Transfer Reagent for Synthesis of Substituted Thioureas
作者:Pramod K. Mohanta、Sanchita Dhar、S.K. Samal、H. Ila、H. Junjappa
DOI:10.1016/s0040-4020(99)01026-1
日期:2000.1
1-(Methyldithiocarbonyl)imidazole 1 and its N-methyl quaternary salt 2 have been shown to be efficient methyldithiocarbonyl and thiocarbonyl transfer reagents for the synthesis of dithiocarbamates, symmetrical and unsymmetrical mono-, di- and tri-substituted thioureas in high yields under mild and simple non-hazardous reaction conditions.