4223-24-9Relevant academic research and scientific papers
METHOD FOR PRODUCING CARBAMATE AND METHOD FOR PRODUCING ISOCYANATE
-
Paragraph 0367-0368; 0379-0381; 0399-0401; 0405-0408; 0410, (2021/06/22)
The present invention provides a method for producing a carbamate that includes a step (1) and a step (2) described below: (1) a step of producing a compound (A) having a urea linkage, using an organic primary amine having at least one primary amino group per molecule and at least one compound selected from among carbon dioxide and carbonic acid derivatives, at a temperature lower than the thermal dissociation temperature of the urea linkage; and(2) a step of reacting the compound (A) with a carbonate ester to produce a carbamate.
Using carbon dioxide diarylbutadiene isocyanate production method (by machine translation)
-
Paragraph 0129, (2017/01/02)
PROBLEM TO BE SOLVED: To provide a method in which there are not various problems shown in a prior art when isocyanate is manufactured without using phosgene, and that can stably manufacture isocyanate for the long period of time in good yield. SOLUTION: The manufacturing method of isocyanate includes: a process in which diaryl carbonate and an amine compound are made to react in the presence of an aromatic hydroxy compound as a reaction solvent, thereby a reaction mixture that includes carbamic acid aryl having an aryl group originated from diaryl carbonate, an aromatic hydroxy compound originated from diaryl carbonate, and diaryl carbonate is obtained; a process in which the reaction mixture is transported to a thermal cracking reactor; and a process in which the carbamic acid aryl is subjected to a thermal decomposition reaction to obtain isocyanate, wherein a reactor in which the reaction of diaryl carbonate and an amine compound is performed and a thermal cracking reactor of carbamic acid aryl are different. COPYRIGHT: (C)2013,JPO&INPIT
PROCESS FOR THE PREPARATION OF N-SUBSTITUTED CARBAMIC ACID ESTER AND PROCESS FOR THE PREPARATION OF ISOCYANATE USING THE N-SUBSTITUTED CARBAMIC ACID ESTER
-
Page/Page column 257-258, (2011/06/10)
The present invention provides a method for producing N-substituted carbamic acid-O-aryl ester derived from a compound having an ureido group, the method comprising the step of carrying out esterification or esterification and transesterification from the compound having the ureido group and a hydroxy composition containing one type or a plurality of types of hydroxy compounds.
PROCESS FOR PRODUCING ISOCYANATE USING DIARYL CARBONATE
-
Page/Page column 50, (2011/02/18)
An object of the present invention is to provide a process that enables isocyanate to be produced stably over a long period of time and at high yield without encountering problems of the prior art during production of isocyanate without using phosgene. The present invention provides an isocyanate production process including the steps of: obtaining a reaction mixture containing an aryl carbamate having an aryl group originating in a diaryl carbonate, an aromatic hydroxy compound originating in a diaryl carbonate, and a diaryl carbonate, by reacting a diaryl carbonate and an amine compound in the presence of a reaction solvent in the form of an aromatic hydroxy compound; transferring the reaction mixture to a thermal decomposition reaction vessel; and obtaining isocyanate by applying the aryl carbamate to a thermal decomposition reaction, wherein the reaction vessel in which the reaction between the diaryl carbonate and the amine compound is carried out and the thermal decomposition reaction vessel for the aryl carbamate are different.
PROCESS FOR PRODUCING ISOCYANATES USING DIARYL CARBONATE
-
Page/Page column 39-40, (2011/04/14)
An object of the present invention is to provide a process that enables isocyanate to be produced stably over a long period of time and at high yield without encountering problems of the prior art during production of isocyanate without using phosgene. The present invention provides an isocyanate production process including the steps of: obtaining a reaction mixture containing an aryl carbamate having an aryl group originating in a diaryl carbonate, an aromatic hydroxy compound originating in a diaryl carbonate, and a diaryl carbonate, by reacting a diaryl carbonate and an amine compound in the presence of a reaction solvent in the form of an aromatic hydroxy compound; transferring the reaction mixture to a thermal decomposition reaction vessel; and obtaining isocyanate by applying the aryl carbamate to a thermal decomposition reaction, wherein the reaction vessel in which the reaction between the diaryl carbonate and the amine compound is carried out and the thermal decomposition reaction vessel for the aryl carbamate are different.
Mixed anhydrides: Key intermediates in carbamates forming processes of industrial interest
Aresta, Michele,Dibenedetto, Angela
, p. 685 - 690 (2007/10/03)
Mixed anhydrides of carbonic acid with phosphonic or carbamic acid, are mimic of relevant biological systems, and behave as key intermediates in transesterification processes that afford carbamates of industrial interest. They are formed in the phosphonic acids mediated or direct transesterification reaction of organic carbonates with amines to afford carbamates and have been isolated and characterised in the solid state and solution. Their conversion into the products has been demonstrated to occur with high regioselectivity. The application of such intermediates in some synthetic processes is discussed.
Process for producing aryl carbamates
-
, (2008/06/13)
PCT No. PCT/JP98/00592 Sec. 371 Date Oct. 13, 1998 Sec. 102(e) Date Oct. 13, 1998 PCT Filed Feb. 13, 1998 PCT Pub. No. WO98/35936 PCT Pub. Date Aug. 20, 1998A process for producing an aryl carbamate of a high purity at a high yield by reacting a diaryl carbonate with an amine compound having one or more hydrogen atoms bonded to the N position in the presence of carboxylic acid(s) of the following general formulae (I): R1-COOH and/or (II): R2-COOH (wherein R1 represents an alkyl or cycloalkyl group having an alpha -positioned carbon atom bonded to only one hydrogen atom, an alkyl group having an alpha -positioned carbon atom bonded to no hydrogen atom, or an aryl or heterocyclic group, and R2 represents an alkyl group having an alpha -positioned carbon atom bonded to two or more hydrogen atoms).
Reaction of aromatic diamines with diphenylcarbonate catalyzed by phosphorous acids: A new clean synthetic route to mono- and dicarbamates
Aresta, Michele,Dibenedetto, Angela,Quaranta, Eugenio
, p. 14145 - 14156 (2007/10/03)
In the presence of organophosphorus acids [Ph2P(O)OH, (PhO)2P(O)OH, (BuO)2P(O)OH, (BuO)P(O)(OH)2], aromatic diamines, such as 4,4'- methylendianiline (MDA) or 2,4-diaminotoluene (TDA), react with diphenylcarbonate (DPC) to afford in a very selective way mono- and dicarbamate phenyl esters. The carbamation process is strongly influenced by the temperature and solvent. The influence of both these factors on carbamate yield and selectivity has been investigated and we present in this study the kinetics of formation of both mono- and dicarbamate esters.
Scorch inhibited vulcanizable rubber compositions containing carbamic acid esters
-
, (2008/06/13)
A novel class of N-sulfenyl derivatives of di(carbamic acid esters) are described. The new compounds inhibit premature vulcanization of rubber.
