- Green and efficient synthesis of thioureas, ureas, primary: O -thiocarbamates, and carbamates in deep eutectic solvent/catalyst systems using thiourea and urea
-
An efficient and general catalysis process was developed for the direct preparation of various primary O-thiocarbamates/carbamates as well as monosubstituted thioureas/ureas by using thiourea/urea as biocompatible thiocarbonyl (carbonyl) sources. This procedure used choline chloride/tin(ii) chloride [ChCl][SnCl2]2 with a dual role as a green catalyst and reaction medium to afford the desired products in moderate to excellent yields. Moreover, the DES can be easily recovered and reused for seven cycles with no significant loss in its activity. Besides, the method shows very good performance for synthesizing the desired products on a large scale.
- Bagherzadeh, Nastaran,Sardarian, Ali Reza,Inaloo, Iman Dindarloo
-
supporting information
p. 11852 - 11858
(2021/07/12)
-
- Triazinetriamine-derived porous organic polymer-supported copper nanoparticles (Cu-NPs@TzTa-POP): an efficient catalyst for the synthesis of: N -methylated products via CO2fixation and primary carbamates from alcohols and urea
-
In recent times, carbon dioxide fixation has received much attention for its potential application as an abundant C1 source and a range of important fine chemicals can be manufactured via this fixation. Here, a copper nanoparticle-decorated porous organic polymer-based (Cu-NPs@TzTa-POP) material was prepared by a simple in situ process. The catalyst was characterized by various techniques such as UV-vis spectra, FTIR spectra, HR-TEM, PXRD, N2 adsorption-desorption, TG-DTA, XPS, and AAS analysis. The synthesized heterogeneous catalyst showed excellent activity in an atmospheric carbon dioxide fixation reaction to produce N-methylated products from aromatic/heterocyclic amines in the presence of polymethyl-hydrosiloxane (PMHS) as the reducing agent at 80 °C within 12 h of the reaction. Through this catalytic N-methylation reaction, we obtained 98% yield of the product with turnover frequency ranging from 18 to 42 h-1. The catalyst is also very stable for the formation of primary carbamates from alcohols using the eco-friendly carbonylating agent, urea. Diverse alcohols (such as benzylic alcohols, phenols, heterocyclic alcohols, as well as aliphatic alcohols) showed much acceptance to this catalytic reaction and produced moderate to excellent yields of the respective carbamate products under ambient reaction conditions. Moreover, Cu-NPs@TzTa-POP is effortlessly recyclable and reusable without the extensive loss of active copper metal centres for many catalytic rounds (up to six catalytic rounds were examined).
- Haque, Najirul,Biswas, Surajit,Basu, Priyanka,Haque Biswas, Imdadul,Khatun, Resmin,Khan, Aslam,Islam, Sk Manirul
-
supporting information
p. 15446 - 15458
(2020/10/22)
-
- An efficient one-pot synthesis of industrially valuable primary organic carbamates and: N -substituted ureas by a reusable Merrifield anchored iron(ii)-anthra catalyst [FeII(Anthra-Merf)] using urea as a sustainable carbonylation source
-
An efficient synthesis of primary carbamates and N-substituted ureas is explored with a newly developed heterogeneous polymer supported iron catalyst in the presence of a sustainable carbonylation source. The Merrifield anchored iron(ii)-anthra catalyst [FeII(Anthra-Merf)] was synthesized by functionalization of Merrifield polymer followed by grafting of iron metal. The catalyst [FeII(Anthra-Merf)] was characterized by several techniques, like SEM, EDAX, TGA, PXRD, XPS, FTIR, CHN, AAS and UV-Vis analysis. The designed polymer embedded [FeII(Anthra-Merf)] complex is a remarkably successful catalyst for the synthesis of primary organic carbamates and N-substituted ureas by using safe carbonylation agent urea with different derivatives of alcohols and amines, respectively. The reported catalyst is a potential candidate towards contributing a satisfactory yield of isolated products under suitable reaction conditions. The catalyst is recyclable and almost non-leaching in nature after six runs with an insignificant drop in catalytic activity. Thus we found an economical and viable catalyst [FeII(Anthra-Merf)] for primary carbamates and N-substituted urea synthesis under moderate reaction conditions.
- Basu, Priyanka,Dey, Tusar Kanto,Ghosh, Aniruddha,Biswas, Surajit,Khan, Aslam,Islam, Sk. Manirul
-
p. 2630 - 2643
(2020/02/20)
-
- An Fe3O4@SiO2/Schiff base/Cu(ii) complex as an efficient recyclable magnetic nanocatalyst for selective mono: N-arylation of primary O-alkyl thiocarbamates and primary O-alkyl carbamates with aryl halides and arylboronic acids
-
An efficient, convenient and novel method for the selective mono N-arylation of primary O-alkyl thiocarbamates and primary O-alkyl carbamates with aryl halides and arylboronic acids in the presence of a recyclable magnetic Cu(ii) nanocatalyst is described. A variety of mono N-arylated O-alkyl thiocarbamates and O-alkyl carbamates were prepared in good to excellent yields with a broad range of aryl coupling partners. The magnetic nanocatalyst can be easily recovered with an external magnetic field and reused at least five times without noticeable leaching or loss of its catalytic activity. This cost-effective and eco-friendly methodology has some other advantages, such as easy preparation of the catalyst, simple workup procedure, and easy purification, which makes this protocol interesting for the users in various fields of pharmacology and biotechnology systems.
- Sardarian, Ali Reza,Dindarloo Inaloo, Iman,Zangiabadi, Milad
-
p. 8557 - 8565
(2019/06/14)
-
- Superparamagnetic Fe3O4 Nanoparticles in a Deep Eutectic Solvent: An Efficient and Recyclable Catalytic System for the Synthesis of Primary Carbamates and Monosubstituted Ureas
-
Superparamagnetic Fe3O4 nanoparticles were used to synthesize various primary carbamates as well as monosubstituted and N,N-disubstituted ureas. This efficient phosgene-free process used urea as an eco-friendly carbonyl source in the presence of a biocompatible deep eutectic solvent (DES) to provide an inexpensive and attractive route that afforded the products in moderate to excellent yields. The employed DES serves both a catalytic role and as the green reaction medium. The magnetic nanocatalyst and DES can been reused several times without a significant loss of activity.
- Inaloo, Iman Dindarloo,Majnooni, Sahar,Esmaeilpour, Mohsen
-
p. 3481 - 3488
(2018/07/29)
-
- Selective Synthesis of Secondary Arylcarbamates via Efficient and Cost Effective Copper-Catalyzed Mono Arylation of Primary Carbamates with Aryl Halides and Arylboronic Acids
-
Abstract: An efficient, selective and cost-effective procedure has been developed for mono N-arylation of primary alkyl and benzyl carbamates with aryl iodides and bromides by incorporating CuI as an inexpensive and commercially available catalyst. Despite previous reports on C–N coupling reactions, this process does not need expensive ligands and takes advantage of readily available and inexpensive ethylenediamine (EDA) as the ligand. Reaction times were relatively short and related N-arylated carbamates were obtained in excellent yields. Interestingly, replacing CuI with Cu(OAc)2 allowed us to use arylboronic acids as coupling partner for this reaction. All products are well characterized by 1H- and 13C-NMR, MS, melting point, IR and CHNS techniques.
- Sardarian, Ali Reza,DindarlooInaloo, Iman,Zangiabadi, Milad
-
p. 642 - 652
(2018/01/11)
-
- Fe3O4@SiO2/Schiff base/Pd complex as an efficient heterogeneous and recyclable nanocatalyst for chemoselective: N -arylation of O -alkyl primary carbamates
-
An efficient, heterogeneous and cost effective method has been developed using an Fe3O4@SiO2/Schiff base/Pd complex as a magnetic and easily recyclable nanocatalyst for rapid and effective N-arylation of carbamates in good to excellent yield. The catalyst can be easily recovered and reused over six runs without significant decrease in the activity. Further highlights of this protocol are operational simplicity, versatility and relatively short reaction times.
- Sardarian,Zangiabadi,Inaloo, I. Dindarloo
-
p. 92057 - 92064
(2016/10/11)
-
- 4-Dodecylbenzenesulfonic acid (DBSA) promoted solvent-free diversity-oriented synthesis of primary carbamates, S-thiocarbamates and ureas
-
A simple and highly efficient solvent-free method for the conversion of alcohols, phenols, thiols and amines to primary carbamates, S-thiocarbamates and ureas in the presence of 4-dodecylbenzenesulfonic acid (DBSA) as a cheap and green Bronsted acid reagent has been described. All products were obtained in good to excellent yields and characterized using FT-IR, 1H- and 13C-NMR, MS and CHNS techniques.
- Sardarian, Ali Reza,Inaloo, Iman Dindarloo
-
p. 76626 - 76641
(2015/09/22)
-
- Ultrasonic and photochemical degradation of chlorpropham and 3-chloroaniline in aqueous solution
-
Sonolysis and photolysis are compared for the transformation of chlorpropham, a systemic herbicide belonging to the carbamate group, and 3-chloroaniline, the main intermediate often observed in the degradation of chlorpropham. In both cases the ultrasonic degradation is much more efficient at 482 kHz than at 20 kHz. The main identified sonoproducts formed in the degradation of chlorpropham are 3-chloroaniline, formic acid, carbon monoxide and dioxide and chloride ions. The degradation of 3-chloroaniline also leads to Cl-, CO and CO2 but chlorohydroquine was also detected as an intermediate. Two different mechanisms are involved in the ultrasonic transformation: pyrolysis resulting from the implosion of cavitation microbubbles and oxidation by hydroxyl radicals formed by sonolysis of water. Photolysis is more specific: 3-chloroaniline is initially quantitatively transformed into 3-aminophenol. A heterolytic mechanism is suggested. Resorcinol and some unidentified photoproducts are formed in a second stage. The same type of reaction is involved in the photo-transformation of chlorpropham, but the reaction is not so specific. In both cases the photolysis at 254 nm leads to a complete disappearance of phenolic and quinonic compounds. Sonolysis and photolysis are compared for the transformation of chlorpropham, a systemic herbicide belonging to the carbamate group, and 3-chloroaniline, the main intermediate often observed in the degradation of chlorpropham. In both cases the ultrasonic degradation is much more efficient at 482 kHz than at 20 kHz. The main identified sonoproducts formed in the degradation of chlorpropham are 3-chloroaniline, formic acid, carbon monoxide and dioxide and chloride ions. The degradation of 3-chloroaniline also leads to Cl-, CO and CO2 but chlorohydroquine was also detected as an intermediate. Two different mechanisms are involved in the ultrasonic transformation: pyrolysis resulting from the implosion of cavitation microbubbles and oxidation by hydroxyl radicals formed by sonolysis of water. Photolysis is more specific: 3-chloroaniline is initially quantitatively transformed into 3-amino-phenol. A heterolytic mechanism is suggested. Resorcinol and some unidentified photoproducts are formed in a second stage. The same type of reaction is involved in the photo-transformation of chlorpropham, but the reaction is not so specific. In both cases the photolysis at 254 nm leads to a complete disappearance of phenolic and quinonic compounds.
- David,Lhote,Faure,Boule
-
p. 2451 - 2461
(2007/10/03)
-
- ALCOHOLYSIS OF 1,2-BIS(1-ISOCYANATO-1-METHYLETHYL)DIAZENE: UNEXPECTED FORMATION OF 5,5-DIMETHYL-1,2,4-TRIAZOLIN-2-ONE
-
From the reaction of the bis(isocyanatoalkyl)diazene 1 with alcohols the expected adducts 2 could not be isolated (though there is spectroscopic evidence of their formation).The main product obtained was the triazolin-3-one 3, and in addition, several complementing products 4-6 were formed.
- Schantl, Joachim G.,Gstach, Hubert,Lanznaster, Norbert
-
p. 1439 - 1444
(2007/10/02)
-
