Copper-Catalyzed One-Pot Synthesis of Unsymmetrical Arylurea Derivatives via Tandem Reaction of Diaryliodonium Salts with <i>N</i>-Arylcyanamide
作者:Pengfei Li、Guolin Cheng、Hong Zhang、Xianxiang Xu、Jingyuan Gao、Xiuling Cui
DOI:10.1021/jo501334u
日期:2014.9.5
efficient “one-pot” approach to multiple substituted ureas from N-arylcyanamide and diaryliodoniumsalts has been presented. The two-step procedure involved the weak base-promoted chemoselective arylation of secondary amines with diaryliodonium and Cu-catalyzed nucleophilic addition of N-arylcyanamide with second diaryliodonium. The diverse unsymmetrical arylureas were obtained in up to 91% yield for 29 examples
aldehydes to cyanamides was developed featuring a wide substrate scope and great functional group tolerability. This method allows for transformations of readily available, inexpensive, and abundant aldehydes to highly valuable cyanamides in a pot, atom, and step-economical manner with a green nitrogen source. This protocol will serve as a robust tool for the installation of the cyanamide moiety in various
A cascade process for directly converting nitriles (RCN) to cyanamides (RNHCN) <i>via</i> SO<sub>2</sub>F<sub>2</sub>-activated Tiemann rearrangement
作者:Guofu Zhang、Yiyong Zhao、Chengrong Ding
DOI:10.1039/c9ob01547g
日期:——
practical process for the direct conversion of nitriles to cyanamides was newly discovered and exhibited a wide substrate scope as well as great functional group-tolerability (36 examples). In this efficient strategy, the in situ generated amidoximes obtained from the reaction of nitriles with hydroxylamine subsequently underwent Tiemann rearrangement, producing the corresponding cyanamides with great
CF
<sub>3</sub>
SO
<sub>2</sub>
Na as a Bifunctional Reagent: Electrochemical Trifluoromethylation of Alkenes Accompanied by SO
<sub>2</sub>
Insertion to Access Trifluoromethylated Cyclic N‐Sulfonylimines
insertion/cyclization process has been achieved in an undivided cell in an atom-economic fashion. The protocol relies on tandem cyclization of N-cyanamide alkenes by using Langlois' reagent as a source of both CF3 and SO2 under direct anodically oxidative conditions, in which two C-C bonds, two C-X bonds (N-S and S-C), and two rings were formed in a single operation. This transformation enabled efficient construction
Nano Cerium Oxide as a Recyclable Catalyst for the Synthesis of <i>N</i>-Monosubstituted Ureas with the Aid of Acetaldoxime as an effective Water Surrogate
作者:S. Mohammad Sajadi、Mehdi Maham
DOI:10.3184/174751913x13787959859461
日期:2013.10
A new method for the synthesis of N-monosubstituted ureas has been developed by the reaction of cyanamides with acetaldoxime in the presence of nano cerium oxide as an efficient and recyclable catalyst.