109-46-6Relevant articles and documents
Malonic Acid Derivatives on Duty as Electron-Withdrawing Units in Push–Pull Molecules
Klikar, Milan,Jelínková, Veronika,R??i?ková, Zdeňka,Mikysek, Tomá?,Pytela, Old?ich,Ludwig, Miroslav,Bure?, Filip
, p. 2764 - 2779 (2017)
Based on the 2-(N-piperidinyl)thiophene central donor, 32 model push–pull molecules with systematically varied malonic acid-derived peripheral acceptors have been prepared. Further property tuning has been achieved by modifying the π-linker and the structural arrangement (linear vs. quadrupolar D–π–A systems). Malonic acid derivatives such as cyanoacetic acid, malondinitrile, diethyl malonate, Meldrum′s acid, and N,N′-dibutyl(thio)barbituric acid as well as 1,3-diketo analogues dimedone and indan-1,3-dione were employed as acceptor moieties. Knoevenagel condensation with four thiophene aldehydes afforded the target chromophores in satisfactory yields. The electron-withdrawing abilities of malonic acid acceptors were examined both by experiment including X-ray analysis, differential scanning calorimetry, electrochemistry, and UV/Vis absorption spectroscopy, and by DFT calculations. Details of the structure–property relationships have been elucidated. According to the increasing electron-withdrawing ability, the widely used malonic acid acceptor units can be ordered: diethyl malonate ≤ cyanoacetic acid malondinitrile Meldrum's acid dimedone ≤ N,N′-dibutylbarbituric acid indan-1,3-dione ≤ N,N′-dibutylthiobarbituric acid.
Nickle Catalysis Enables Access to Thiazolidines from Thioureas via Oxidative Double Isocyanide Insertion Reactions
Yuan, Wen-Kui,Liu, Yan Fang,Lan, Zhenggang,Wen, Li-Rong,Li, Ming
supporting information, p. 7158 - 7162 (2018/11/25)
An efficient synthesis of thiazolidine-2,4,5-triimine derivatives was developed via 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 insertion reactions.
Rapid and highly efficient synthesis of thioureas in biocompatible basic choline hydroxide
Azizi, Najmedin,Farhadi, Elham
, p. 548 - 554 (2017/09/27)
A straightforward and convenient synthesis of symmetrical thiourea derivatives by the reaction of primary amines and carbon disulfide in biocompatible basic choline hydroxide is presented. A variety of biologically important thiourea derivatives can be obtained in good to excellent yields without a tedious work-up under mild reaction conditions. A series of primary aliphatic and aromatic amines with different substituted functional groups have been converted to thiourea derivatives under milder reaction conditions and short reaction times.