13105-53-8Relevant academic research and scientific papers
Polymer- and Carbon Nanotube-Supported Heterogeneous Catalysts for the Synthesis of Carbamates from Halides, Amines, and CO2
Krawczyk, Tomasz,Jasiak, Katarzyna,Kokolus, Aneta,Baj, Stefan
, p. 1163 - 1168 (2016)
Abstract: A series of tetraalkylammonium catalysts immobilized on polystyrene or carbon nanotubes were investigated in a reaction between alkyl halides, amines, and CO2. The yield of carbamates was up to 85?% at 100?°C and 1?MPa of CO2 after 3?h (first stage 25?°C, 1 h) in the presence of Cs2CO3 and DMF as a solvent. The best results were achieved in the case of large ammonium substituents (C4 and C6) in the catalyst, benzyl amine, and benzyl chloride as reagents. The catalysts retained their activity after at least five cycles when carefully dried between cycles. Both polymer and carbon nanotube supports were equally effective, but the latter were less prone to deactivation. Graphical Abstract: [Figure not available: see fulltext.]
Design, synthesis and SAR of antitubercular benzylpiperazine ureas
Satish, Sohal,Chitral, Rohan,Kori, Amitkumar,Sharma, Basantkumar,Puttur, Jayashree,Khan, Afreen A.,Desle, Deepali,Raikuvar, Kavita,Korkegian, Aaron,Martis, Elvis A. F.,Iyer, Krishna R.,Coutinho, Evans C.,Parish, Tanya,Nandan, Santosh
, (2021/01/04)
Abstract: N-furfuryl piperazine ureas disclosed by scientists at GSK Tres Cantos were chosen as antimycobacterial hits from a phenotypic whole-cell screen. Bioisosteric replacement of the furan ring in the GSK Tres Cantos molecules with a phenyl ring led to molecule (I) with an MIC of 1?μM against Mtb H37Rv, low cellular toxicity (HepG2 IC50 ~ 80?μM), good DMPK properties and specificity for Mtb. With the aim of delineating the SAR associated with (I), fifty-five analogs were synthesized and screened against Mtb. The SAR suggests that the piperazine ring, benzyl urea and piperonyl moieties are essential signatures of this series. Active compounds in this series are metabolically stable, have low cellular toxicity and are valuable leads for optimization. Molecular docking suggests these molecules occupy the Q0 site of QcrB like Q203. Graphic Abstract: Bioisosteric replacement of N-furfuryl piperazine-1-carboxamides yielded molecule (I) a novel lead with satisfactory PD, metabolism, and toxicity profiles.[Figure not available: see fulltext.]
Carbamate Synthesis Using a Shelf-Stable and Renewable C1 Reactant
Dobi, Zoltán,Reddy, B. Narendraprasad,Renders, Evelien,Van Raemdonck, Laurent,Mensch, Carl,De Smet, Gilles,Chen, Chen,Bheeter, Charles,Sergeyev, Sergey,Herrebout, Wouter A.,Maes, Bert U. W.
, p. 3103 - 3114 (2019/06/24)
4-Propylcatechol carbonate is a shelf-stable, renewable C1 reactant. It is easily prepared from renewable 4-propylcatechol (derived from wood) and dimethyl carbonate (derived from CO2) using a reactive distillation system. In this work, the 4-propylcatechol carbonate is used for the two-step synthesis of carbamates under mild reaction conditions. In the first step, 4-propylcatechol carbonate is treated with an alcohol at 50–80 °C in the presence of a Lewis acid catalyst, such as Zn(OAc)2?2 H2O. With liquid alcohols, no solvent is used and with solid alcohols 2-methyltetrahydrofuran is used as solvent. In the second step, the alkyl 2-hydroxy-propylphenyl carbonate intermediates obtained react with amines at room temperature in 2-methyltetrahydrofuran, forming the target carbamates and the byproduct 4-propylcatechol, which can be recycled into a carbonate reactant.
A Simple, efficient, Catalyst-Free and Solvent-Less Microwave-Assisted process for N-Cbz Protection of Several amines
Aouf, Zineb,Mansouri, Rachida,Lakrout, Salah,Berredjem, Malika,Aouf, Nour-Eddine
, p. 151 - 156 (2017/08/02)
A simple, green and chemo-selective method for the N-benzyloxycarbonylation of amines, β-amino alcohols, α-amino esters and sulfonamides has been developed under microwave irradiation. Good to excellent yields of the N-benzyloxy-carbamates compounds were obtained in short times without any side products.
A facile protocol for N-Cbz protection of amines in PEG-600
Zhang, Chun Lin,Zhang, Dong Feng,Zhao, Hong Yi,Lin, Zi Yun,Huang, Hai Hong
experimental part, p. 789 - 792 (2012/08/08)
An efficient and eco-friendly protocol for the chemoselective N-benzyloxycarbonylation of amines was described. The reaction of amines with benzyl chloroformate (Cbz-Cl) in the presence of PEG-600 at room temperature afforded the corresponding N-Cbz derivatives in excellent yields. The method is applicable to the N-Cbz protection of aliphatic (acyclic and cyclic) and aromatic amines.
Pd-catalyzed N-arylation of secondary acyclic amides: Catalyst development, scope, and computational study
Hicks, Jacqueline D.,Hyde, Alan M.,Cuezva, Alberto Martinez,Buchwald, Stephen L.
supporting information; experimental part, p. 16720 - 16734 (2010/04/04)
We report the efficient N-arylation of acyclic secondary amides and related nucleophiles with aryl nonaflates, triflates, and chlorides. This method allows for easy variation of the aromatic component in tertiary aryl amides. A new biaryl phosphine with P-bound 3,5-(bis)trifluoromethylphenyl groups was found to be uniquely effective for this amidation. The critical aspects of the ligand were explored through synthetic, mechanistic, and computational studies. Systematic variation of the ligand revealed the importance of (1) a methoxy group on the aromatic carbon of the "top ring" ortho to the phosphorus and (2) two highly electron-withdrawing P-bound 3,5-(bis)trifluoromethylphenyl groups. Computational studies suggest the electron-deficient nature of the ligand is important in facilitating amide binding to the LPd(II)(Ph)(X) intermediate.
One-pot, three-step preparation of alkyl and aryl alkylcarbamates from S-methyl N-alkylthiocarbamates
Artuso, Emma,Degani, Iacopo,Fochi, Rita,Magistris, Claudio
experimental part, p. 1612 - 1618 (2009/04/03)
A general procedure for the synthesis of alkyl and aryl alkylcarbamates starting from the corresponding 5-methyl N-alkylthiocarbamates is described. This procedure consists of three steps that are carried out in a one-pot fashion, without isolating the intermediate N-alkylcarbamoyl chlorides or alkyl isocyanates. All the target products were obtained in high yields (16 examples, average yield 91%). To be noted is the recovery of a co-product of industrial interest, dimethyl disulfide, in a half mole amount for each mole of thiocarbamate, with complete exploitation of the reagent. The alkyl isocyanates, if required, can also be isolated in high yields. Georg Thieme Verlag Stuttgart.
A catalyst-free N-benzyloxycarbonylation of amines in aqueous micellar media at room temperature
Shrikhande, Janhavi J.,Gawande, Manoj B.,Jayaram, Radha V.
, p. 4799 - 4803 (2008/12/22)
N-Benzyloxycarbonylation of amines was carried out in aqueous micellar media. Aliphatic (open and cyclic), aromatic and heteroaromatic amines react with Cbz-Cl to give excellent yields of products. The reactions were carried out in water and at room temperature.
A mild and efficient chemoselective protection of amines as N-benzyloxycarbonyl derivatives in the presence of La(NO3)3·6H2O under solvent-free conditions
Chinni Mahesh,Narasimhulu,Srikanth Reddy,Suryakiran,Venkateswarlu
, p. 55 - 59 (2007/10/03)
A facile and versatile method for the chemoselective N-benzyloxycarbonylation of amines has been developed by treatment with benzyloxycarbonyl chloride (Cbz-Cl) in the presence of lanthanum(III) nitrate hexahydrate under solvent-free conditions. The metho
An efficient and chemoselective Cbz-protection of amines using silica-sulfuric acid at room temperature
Gawande, Manoj B.,Polshettiwar, Vivek,Varma, Rajender S.,Jayaram, Radha V.
, p. 8170 - 8173 (2008/03/13)
A simple, facile, and chemoselective N-benzyloxycarbonylation of amines using silica-sulfuric acid that proceeds under solvent-free conditions at room temperature has been achieved. These reactions are applicable to a wide variety of primary (aliphatic and cyclic) secondary amines, amino alcohols, and heterocyclic amines.
