A facile method for the preparation of carbodiimides from thioureas and (Boc) 2 O
作者:He Wu、Yan-Fang Sun、Chen Zhang、Chun-Bao Miao、Hai-Tao Yang
DOI:10.1016/j.tetlet.2018.01.025
日期:2018.2
A concise method for the preparation of carbodiimides from thioureas using di-tert-butyl dicarbonate [(Boc)2O] as the dehydrosulfurizative reagent has been developed. Using DMAP as the catalyst, a variety of symmetric and asymmetric 1,3-diaryl thioureas were converted into the corresponding carbodiimides efficiently in a short time.
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.
Synthesis and Mechanistic Study of Cyclic Oxoguanidines via Zn(OTf)<sub>2</sub>-Catalyzed Guanylation/Amidation from Readily Available Amino Acid Esters and Carbodiimides
作者:Yue Chi、Ling Xu、Shanshan Du、Haihan Yan、Wen-Xiong Zhang、Zhenfeng Xi
DOI:10.1002/chem.201500573
日期:2015.7.13
The Zn(OTf)2‐catalyzed guanylation/amidationfromreadilyavailableaminoacidesters and carbodiimides is achieved to provide efficiently various cyclicoxoguanidines, including 2‐amino‐1H‐imidazol‐5(4H)‐ones and 2‐aminoquinazolin‐4(3H)‐ones in medium‐to‐high yields. It is the first time that an ammonium salt has been used in a guanylation reaction. The application of cyclicoxoguanidines to provide
Cascade Nucleophilic Attack/Addition Cyclization Reactions to Synthesize Oxazolidin-2-imines via (<i>Z</i>)-2-Bromo-3-phenylprop-2-en-1-ols/3-phenylprop-2-yn-1-ols and Diphenyl Carbodiimides
Two concise strategies to synthesize oxazolidin-2-imines by cascade nucleophilic attack/addition cyclization reactions of (Z)-2-bromo-3-phenylprop-2-en-1-ols/3-phenylprop-2-yn-1-ols and diphenyl carbodiimides without a transition-metal catalyst have been developed. The reactions exhibited good substrate applicability tolerance, and a variety of substituted (Z)-4-((Z)-benzylidene)-N,3-diphenyloxazolidin-2-imines
( Z )-2-bromo-3-phenylprop-2-en-1-ols/3-phenylprop-2-yn-1-ols的级联亲核攻击/加成环化反应合成恶唑烷-2-亚胺的两种简明策略已经开发了没有过渡金属催化剂的二苯基碳二亚胺。该反应表现出良好的底物适用性,以中等至优异的收率合成了多种取代的( Z )-4-(( Z )-亚苄基) -N ,3-二苯恶唑烷-2-亚胺,具有良好的立体选择性。该报告还提供了一种方便的策略来合成 3-phenylprop-2-yn-1-ols ( Z)-2-bromo-3-phenylprop-2-en-1-ols。经济实用的方法为恶唑烷-2-亚胺的潜在工业合成提供了很大的优势。
Cobalt(II)-Catalyzed Directed C–H Functionalization/[3+2] Annulation of <i>N</i>-Arylguanidines with Alkynes
作者:Harish Parihar、Natesan Thirupathi
DOI:10.1021/acs.orglett.2c02503
日期:2022.11.11
A family of N,N′-diaryl-N″-(quinolin-8-yl)guanidines were prepared by two methods, and these guanidines were subjected to Co(II)-catalyzed C–H functionalization/annulation with terminal and internal alkynes under mild conditions to afford a family of indole guanidines. Substrates with a range of electronic and steric properties were tolerated. The fluxionalbehavior of two guanidines and molecular
通过两种方法制备了一系列 N , N ′-二芳基-N ″-(喹啉-8-基)胍,这些胍被 Co(II) 催化的 C-H 官能化/末端和内部炔环化在温和的条件下得到一族吲哚胍。具有一系列电子和空间特性的底物是可以接受的。报道了两种胍的流动行为和九种化合物的分子结构。进行了几个关键实验来支持所提出的炔烃环化机制。