121928-40-3Relevant academic research and scientific papers
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.
Ph3P/I2-mediated synthesis of N,N′,N″-substituted guanidines and 2-iminoimidazolin-4-ones from aryl isothiocyanates
Wangngae, Sirilak,Pattarawarapan, Mookda,Phakhodee, Wong
, p. 10331 - 10340 (2018/05/31)
A convenient one-pot procedure for the synthesis of acyclic and cyclic guanidines mediated by the Ph3P/I2 system is described. Sequential condensation of aryl isothiocyanates with amines followed by dehydrosulfurization and guanylation could lead to both symmetric and unsymmetric N,N′,N″-substituted derivatives. Through a tandem guanylation-cyclization, a series of 2-iminoimidazolin-4-ones could also be prepared in good yields from the reaction of aryl isothiocyanates with amino acid methyl esters.
2-AMINO-SUBSTITUTED DERIVATIVES OF BENZIMIDAZOLES FROM 2-ISOTHIOCYANATO CARBOXYLATES
Floch, Lubomir,Uher, Michal,Lesko, Jan
, p. 206 - 214 (2007/10/02)
2-isothiocyanato carboxylates react with o-phenylenediamine to give N,N'-substituted thioureas, which cyclize to yield 2-amino-substituted derivatives of imidazole.The structure of these compounds was corroborated by IR, UV, 1H, 13C NMR, and mass spectral
BASE CATALYZED CYCLIZATION OF SUBSTITUTED ESTERS OF HYDANTOIC AND THIOHYDANTOIC ACID
Kavalek, Jaromir,Machacek, Vladimir,Svobodova, Gabriela,Sterba, Vojeslav
, p. 375 - 390 (2007/10/02)
Base catalyzed cyclization rates have been measured of 22 derivatives of hydantoic and thiohydantoic acid esters in water and methanol.The cyclization of methyl and ethyl esters of hydantoic and 5-methylhydantoic acids is accompanied by hydrolysis of the ester group, whereas with the other derivatives the hydrolysis does not take place.Hydrolysis of the cyclization products (hydantoin and thiohydantoin derivatives) is not significant under the kinetic conditions.The cyclization of methyl ester of 5-phenylhydantoic acid in methanol is reversible; the equilibrium mixture contains 30percent of the starting ester.In all the cases the cyclization is subject to specific base catalysis; exceptions are esters of 5-phenylthiohydantoic and 5-phenyl-2-methylthiohydantoic acids whose cyclizations are subject to general base catalysis.Substituents always accelerate the cyclization.The 3-substituents have the greatest effects, the cyclization rate being considerably increased with bulk of the substituents; similarly large effect of 5-phenyl group consists mainly in its polar effects on the pre-equilibrium.The cyclizations are slower in methanol at the same concentration of the lyate ion: the greatest difference (up to 3 orders of magnitude) is observed with the 5-phenyl derivatives.
