28147-81-1Relevant academic research and scientific papers
Method for preparing methyl carbamate by catalyzing methanol conversion
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Paragraph 0039, (2018/01/09)
The invention discloses a method for preparing methyl carbamate by catalyzing methanol conversion. The method specifically comprises: taking oxygen or air as an oxygen source, taking organic amine as a nitrogen source, taking methanol as a solvent, in the function of a catalyst, allowing methanol to undergo ammoxidation to generate methanamide, and allowing methanamide to undergo in-situ oxidation esterification to obtain methyl carbamate. The method is high in raw material utilization rate. The catalyst is cheap and available, is easy to recycle, can be reused, and is easy to separate from the product. The obtained methyl carbamate is excellent in performance and high in purity. The technical route is of great significance in releasing excess production capacity of methanol and reducing the dependence on highly toxic chemicals.
A novel and efficient strategy for the synthesis of various carbamates using carbamoyl chlorides under solvent-free and grinding conditions using microwave irradiation
Zare, Hassan,Ghanbari, Mohammad Mehdi,Jamali, Marzieh,Aboodi, Abdollah
experimental part, p. 883 - 886 (2012/08/28)
We present an efficient, fast and simple strategy of generating the intermediate carbamoyl chlorides from secondary amines using stoichiometric amounts of bis(trichloromethyl)carbonate (BTC) in solution and solvent-free conditions with excellent yields. The results obtained showed the yield increasing on whether a base was used. Finally, an efficient and rapid synthesis of variety carbamate derivatives was developed by the reaction with a high variety of different alcohols, phenols, diols and this intermediate at room temperature with grinding and in solvent-free conditions under microwave irradiation. The presence of various safe bases is shown to be effective in reducing the reaction times, increasing the yields and easing purification. The present method does not involve any hazardous phosgene.
Mild and convenient synthesis of organic carbamates from amines and carbon dioxide using tetraethylammonium superoxide
Singh, Krishna Nand
, p. 2651 - 2654 (2008/02/12)
A safe and simple method of preparing organic carbamates has been achieved from amines and carbon dioxide using tetraethylammonium superoxide generated in situ. Copyright Taylor & Francis Group, LLC.
METHOD FOR THE ORGANOMETALLIC PRODUCTION OF ORGANIC INTERMEDIATE PRODUCTS COMPRISING CARBON-HETEROATOM BONDS ACHIEVED BY THE DEPROTONATION OF HETEROATOMS
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Page/Page column 13, (2008/06/13)
The invention relates to a method for binding heteroatom-carbon bonds. According to said method, a lithium compound (II) is first generated by reacting aliphatic or aromatic halogen compounds (I) with lithium metal, said compound is then used for the deprotonation of the compounds (III) or (V). The lithium salts of formulas (IV) or (VI) obtained by said deprotonation are subsequently reacted with suitable carbon electrophiles (equation I), said process binding the heteroatom-carbon bond and forming the products (VIII) or (VIII), (equation I).
Correlation of the rates of solvolysis of the N,N-diphenylcarbamoylpyridinium ion
Kevill, Dennis N.,Bond, Michael W.,D'Souza, Malcolm J.
, p. 273 - 276 (2007/10/03)
Solvolyses of the N,N-diphenylcarbamoylpyridinium ion are subject to specific and/or general base catalysis, which can be eliminated by addition of perchloric acid or increased, especially in fluoroalcohol-containing solvents, by addition of pyridine. The uncatalyzed solvolyses in aqueous methanol and aqueous ethanol involve a weakly nucleophilically assisted (l=0.22) heterolysis and the solvolyses in the pure alcohols are anomalously slow.
Kinetics and Selectivities for the Solvolysis of N,N-Diphenylcarbamoyl Chloride
D'Souza, Malcolm J.,Kevill, Dennis N.,Bentley, T. William,Devaney, Angela C.
, p. 1632 - 1637 (2007/10/02)
Values for the specific rates of solvolysis of N,N-diphenylcarbamoyl chloride have been analyzed using the two-term Grunwald-Winstein equation, incorporating the NT solvent nucleophilicity scale and the YCl solvent ionizing power scale.The sensitivities of 0.23+/-0.04 to changes in NT and of 0.58+/-0.03 to changes in YCl are consistent with an SN1 pathway with extensive internal nucleophilic assistance and a weak nucleophilic solvation of the developing carbocation.Product studies have been performed in mixtures of water with methanol, ethanol, and 2,2,2-trifluoroethanol (TFE) and in TFE-ethanol mixtures.Giving further support to the proposed SN1 mechanism, both the sensitivity to changes in solvent nucleophilicity and the product selectivities in aqueous ethanol and methanol parallel closely those previously determined for solvolyses of p-methoxybenzoyl chloride.
APPROACH TO THE 1-METHOXY-2-BENZIMIDAZOLINONES
Perronnet, Jacques,Demoute, Jean-Pierre
, p. 507 - 512 (2007/10/02)
With t-butyl hypochlorite the 1-methoxy-3-arylureas are easily converted into the unstable corresponding 1-chloro-1-methoxy-3-arylureas.Cyclization of the latter under basic conditions gives the 1-methoxy-2-benzimidazolinones.The two steps can be carried
Reaktionen mit Aziridinen, XXII. Einstufensynthese von Pyrrolidonen durch Amidoethylierung einfacher Ester mit N-Acylaziridinen
Stamm, Helmut,Woderer, Anton,Wiesert, Wolfgang
, p. 32 - 48 (2007/10/02)
Sodium enolates of simple esters (2) react smoothly with N-acylaziridines (3) in THF forming 3-substituted 2-pyrrolidones 8.If the α-position of the ester carries more than one H-atom amidoethylated pyrrolidones can result.Whilst a simple butyrolactone behaves analogously amidoethylation of coumaranone furnished mono and bis amidoethyl derivatives of coumaranone besides a pyrrolidone. - In tert-butyl alcohol only extremly acidic esters like 1e and 1j could be amidoethylated.
