14803-72-6Relevant academic research and scientific papers
Unexpected Reaction of Oximinoacetoacetate with Amines: A Novel Synthesis of Carbamates
Elghamry, Ibrahim
, p. 3010 - 3015 (2009)
The synthesis of alkyl carbamates by a solvent-free reaction of oximinoacetoacetate and amine at 130C is reported. A preliminary mechanism to this unexpected reaction is also given.
Atomically Dispersed Copper on N-Doped Carbon Nanosheets for Electrocatalytic Synthesis of Carbamates from CO2 as a C1 Source
Li, Shi-Ming,Shi, Yi,Zhang, Jing-Jie,Wang, Ying,Wang, Huan,Lu, Jia-Xing
, p. 2050 - 2055 (2021)
The synthesis of carbamates by electrocatalytic reduction of CO2 is an effective method to realize the utilization of CO2 resources. The development of high-performance electrocatalysts to complete this process more efficiently is of great significance to sustainable development. Owing to their unique structural characteristics, single-atom catalysts are expected to promote the reaction process more efficiently. In this study, an atomically dispersed Cu species on N-doped carbon nanosheet composite material (Cu?N?C) was prepared by metal-organic framework derivatization. Compared with traditional Cu bulk electrodes, the Cu?N?C material has better catalytic performance for the synthesis of methyl N-phenylcarbamate; and the optimized yield reached 71 % at room temperature and normal pressure. The Cu?N?C material has good stability that the catalytic performance does not decrease after repeated use for 10 times. In addition, the Cu?N?C material has good applicability to this catalytic system, and a variety of amines can be smoothly converted into corresponding carbamates.
Preparation of methyl carbamates via a modified Hofmann rearrangement
Huang, Xicai,Keillor, Jeffrey W.
, p. 313 - 316 (1997)
Treatment of a series of para-substituted aromatic and primary aliphatic carboxamides with NBS and NaOMe in methanol heated to reflux for ten minutes results in the conversion of the carboxamides to their corresponding primary amino methyl carbamates in nearly quantitative yields. The mild oxidative conditions of this modified Hofmann rearrangement are shown to be particularly useful for the preparation of p-substituted anilines.
Carbamate synthesis from amines and dimethyl carbonate under ytterbium triflate catalysis
Curini, Massimo,Epifano, Francesco,Maltese, Federica,Rosati, Ornelio
, p. 4895 - 4897 (2002)
A facile synthesis of carbamates from amines and dimethyl carbonate has been achieved using ytterbium triflate as catalyst.
CuSe2/CeO2 as a novel heterogeneous catalyst for reductive carbonylation of nitroarenes for generating urethanes
Tran, Anh Vy,Nguyen, Thanh Tung,Lee, Hye Jin,Bae, Se Won,Baek, Jayeon,Kim, Hoon Sik,Kim, Yong Jin
, (2019)
The reaction of CuCl2, SeO2, and cetyltrimethylammonium bromide (CTAB) under the CO pressure in methanol produce a black solid, which is identified as cupric diselenide, CuIISe2 using various spectroscopic analyses. Impregnation of 5 wt% of CuSe2 onto CeO2 resulted in much more enhanced catalytic activity due to the uniform and highly dispersed particle. The reductive carbonylation of nitrobenzene (NB) as a model substrate has been examined in the presence of the CuSe2/CeO2 as a single component heterogeneous catalyst, which is found to exhibit excellent catalytic activity for generating methyl-N-phenyl carbamate (MPC) in a highly selective fashion. The effects of various reaction parameters such as temperature, pressure, and reaction time have been investigated. A plausible reaction mechanism using this cheap heterogeneous catalyst is also presented, especially invoking the importance of CuSe2(μ-CO) species.
L-Proline-TBAB-catalyzed phosgene free synthesis of methyl carbamates from amines and dimethyl carbonate
Kumar, Subodh,Jain, Suman L.
, p. 2935 - 2938 (2013)
The reaction of amines and dimethyl carbonate (DMC) in the presence of catalytic amounts of l-proline and tetrabutylammonium bromide (TBAB) afforded methyl carbamates in good to excellent yields under mild conditions. The presence of both l-proline and TBAB co-catalysts is vital for this transformation.
TBCA mediated microwave-assisted Hofmann rearrangement
Miranda, Leandro S.M.,Da Silva, Thayane Rabello,Crespo, Lívia Tenório,Esteves, Pierre Moth,De Matos, Louise F.,Diederichs, Carla C.,De Souza, Rodrigo Octávio Mendona Alves
, p. 1639 - 1640 (2011)
A protocol for the microwave-assisted Hofmann rearrangement mediated by TBCA/KOH/MeOH was developed. Under these conditions high yields and short reaction times were observed for aromatic benzamides.
Reductive Carbonylation of Nitroarenes Using a Heterogenized Phen-Pd Catalyst
Padmanaban, Sudakar,Ganesan, Vinothkumar,Yoon, Sungho,Lee, Yunho
, p. 1552 - 1561 (2022/01/27)
The reductive carbonylation of nitroarenes in the presence of MeOH and CO(g) is one of the interesting alternative routes without utilizing toxic phosgene and corrosive HCl generation for the synthesis of industrially useful carbamate compounds that serve as important intermediates for polyurethane production. Since homogeneous palladium catalysts supported by phen (phen = 1,10-phenanthroline) are known to be effective for this catalysis, the heterogenized Pd catalyst was developed using the phen-containing solid support. In this study, we report the synthesis of a phen-based heterogeneous Pd catalyst, Pd@phen-POP, which involves the solvent knitting of a phen scaffold via the Lewis-acid-catalyzed Friedel-Crafts reaction using dichloromethane as a source for linker in the presence of AlCl3 as a catalyst. The resulting solid material has been thoroughly characterized by various physical methods revealing high porosity and surface area. Similar to the homogeneous pallidum catalyst, this heterogeneous catalyst shows efficient reductive carbonylation of various nitroarenes. The catalytic reaction using nitrobenzene as a model compound presents a high turnover number (TON = 530) and a reasonable turnover frequency (TOF = 45 h-1), with a high selectivity (92%) for the carbamate formation. According to the recycling study, the heterogeneous catalyst is recyclable and retains ～90% of the original reactivity in each cycle.
METHOD FOR PRODUCING CARBAMATE
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Paragraph 0014-0024, (2021/08/13)
PROBLEM TO BE SOLVED: To provide a method that can produce carbamate with high yield and high selectivity, and excellent economical efficiency, using more different kinds of amines. SOLUTION: A method for producing carbamate has a reaction step where, in the presence of calcium carbide and potassium carbonate, a reaction is induced among amine, methanol, and carbon dioxide. The reaction step is preferably performed at a temperature of 165-180°C. The reaction step is preferably performed at a carbon dioxide pressure of 3-5 MPa. The reaction step is preferably performed using an acetonitrile solvent. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2021,JPOandINPIT
Copper-Catalyzed Coupling of Amines with Carbazates: An Approach to Carbamates
Wang, Song-Ning,Zhang, Guo-Yu,Shoberu, Adedamola,Zou, Jian-Ping
, p. 9067 - 9075 (2021/07/19)
A new approach for the preparation of carbamatesviathe copper-catalyzed cross-coupling reaction of amines with alkoxycarbonyl radicals generated from carbazates is described. This environmentally friendly protocol takes place under mild conditions and is compatible with a wide range of amines, including aromatic/aliphatic and primary/secondary substrates.
