Abstract: Novel aromatic diisocyanate and a method of producing the same. The method comprises reacting a diamine compound with a chloroformate to produce an urethane intermediate, and then reacting the urethane intermediate with a halogenated organosilicon compound or a halogenated organoboron compound, using an organic solvent capable of dissolving both the diamine compound and the urethane intermediate. This method enables to produce the aromatic diisocyanate by one-pot. The aromatic diisocyanate has excellent various properties such as high heat resistance and chemical resistance.
Abstract: Diisocyanates containing carboxylic acid ester groups corresponding to the formula: ##STR1## in which R and R.sup.1 represent specified groups are produced by phosgenation of the corresponding diamines, optionally present in the form of an ammonium salt. These diisocyanates are useful as starting materials in the production of plastics containing urethane and/or urea groups and as starting materials for the production of intermediate products used for the production of such plastics.
Type:
Grant
Filed:
May 3, 1995
Date of Patent:
September 3, 1996
Assignee:
Bayer Aktiengesellschaft
Inventors:
Christian Wamprecht, Klaus Jost, Stefan Penninger
Abstract: Aromatic polyisocyanates, e.g., toluene diisocyanate, are prepared by reacting/contacting at least one aromatic compound (A) bearing at least two primary amine substituents, e.g., toluenediamine, xylylenediamine and/or phenylenediamine,, with phosgene, in gaseous phase and in a reactor/reaction zone devoid of active mechanical stirring.
Abstract: The invention concerns a process for the preparation of acyl isocyanates which consists of reacting oxalyl chloride with a salt selected from the group consisting of hydrohalides and sulphates of carboxamides and/or carbamates, unsubstituted on nitrogen, then heating the reaction mixture at a temperature between 30.degree. and 150.degree. C. The process is suitable for preparation of acyl isocyanates with excellent yields in easy to control operational conditions.
Type:
Grant
Filed:
August 2, 1993
Date of Patent:
January 31, 1995
Assignees:
Societe Nationale des Poudres et Explosifs, Nippon Paint Co. Ltd.
Inventors:
Philippe Le Goff, Daniele Dewilde, Noriyuki Tsuboniwa, Satoshi Urano
Abstract: A process for preparing isocyanates comprising (a) contacting carbon dioxide and a primary amine in the presence of an aprotic organic solvent and a base selected from the group consisting of a phosphazene compound, an organic, nitrogenous base and mixtures thereof, wherein the organic, nitrogenous base selected from the group consisting of guanidine compounds, amidine compounds, tertiary amines, pyridine and mixtures thereof to produce the corresponding ammonium carbamate salt, and (b) reacting the ammonium carbamate salt with an electrophilic or oxophilic dehydrating agent to produce the corresponding isocyanate.
Abstract: A method for preparing isocyanates by the thermal decomposition of carbamates in the presence of a sintered oxide as catalyst under gaseous phase condition. The sintered oxide is composed of at least one element selected from the group consisting of boron, aluminum, silicon, tin, lead, antimony, zinc, yttrium, lanthanum, titanium, zirconium, niobium, tungsten, and iron. The sintered oxide may be composed of at least one element selected from the group consisting of phosphorus, alkali metal element, and alkaline earth metal element.
Abstract: The present invention relates to a process for preparation of an isocyanate comprising (a) reacting an amide with an aqueous solution of hypochlorous acid in the presence of an water-immiscible organic solvent to produce an N-chloro amide; and (b) reacting said N-chloro amide with a base in the presence of a phase transfer catalyst and a water immiscible organic solvent to produce an isocyanate.
Abstract: Multistep process for the preparation of alkyl mono and diisocyanates consisting in reacting the corresponding aliphatic amine or diamine with dimethylcarbonate and, substantially, in partially vaporizing and converting the urethane thus formed in an evaporator to subsequently terminate the cracking in a II.degree. reactor, and finally subjecting the cracking product to fractional distillation at reduced pressure, recycling the unconverted part to the partial vaporization step.
Type:
Grant
Filed:
May 11, 1993
Date of Patent:
May 24, 1994
Assignee:
Enichem Synthesis S.p.A.
Inventors:
Franco Mizia, Franco Rivetti, Ugo Romano
Abstract: Saturated, liquid, low molecular weight and low-viscosity isobutylene polymers terminally functionalized by special groups, which correspond to the following formula ##STR1## are produced by solution ozonolysis of high molecular weight isobutylene/diene copolymers containing diene monomers, stabilization of the products obtained after the ozone treatment by addition of peroxide decomposers and subsequent reduction with hydrogen in the presence of hydrogenation catalysts under pressures of 10 to 300 bar and at temperatures of 20.degree. to 300.degree. C., optionally in the presence of sulfur or amines or ammonia.
Abstract: A process for preparing an isocyanate having at least two --N.dbd.C.dbd.O groups is provided which comprises preparing a substituted aromatic amine having at least two --NH.sub.2 groups, recovering the substituted aromatic amine having at least two --NH.sub.2 groups, and preparing an isocyanate from the substituted aromatic amine having at least two --NH.sub.2 groups by (1) contacting the substituted aromatic amine with CO.sub.2 under conditions sufficient to produce the corresponding ammonium carbamate salt, and reacting the ammonium carbamate salt with an electrophilic or oxophilic dehydrating agent under conditions sufficient to produce the corresponding isocyanate, or (2) contacting the substituted aromatic amine with CO.sub.
Type:
Grant
Filed:
October 15, 1992
Date of Patent:
August 3, 1993
Assignee:
Monsanto Company
Inventors:
William D. McGhee, Michael K. Stern, Thomas E. Waldman
Abstract: The present invention is directed to a process of preparing isocyanate-substituted isophthaloyl chloride by heating a mixture of amino-substituted isophthalic acid, catalyst, phosgene and halogenated solvent under autogeneous pressure.
Abstract: A process for preparing isocyanates comprising (a) contacting carbon dioxide and a primary amine in the presence of an aprotic organic solvent and an organic, nitrogenous base to produce the corresponding ammonium carbamate salt, and (b) reacting the ammonium carbamate salt with an electrophilic or oxophilic dehydrating agent to produce the corresponding isocyanate. A second embodiment comprises recovering the ammonium carbamate salt of step (a) prior to reacting the ammonium carbamate salt with an electrophilic or oxophilic dehydrating agent in the presence of an aprotic organic solvent and an organic, nitrogenous base.
Abstract: The present invention relates to a process for producing isocyanates which comprises reacting an N-halogenated amide with an organic base in an essentially water-free modified Hofmann reaction using a soluble silver salt promoter in the presence of an organic solvent. Also disclosed is a process for producing a carbamate which comprises reacting an N-halogenated amide with an organic base in an essentially water-free modified Hofmann reaction using a soluble silver salt promoter in the presence of an alcohol solvent.
Abstract: The present invention relates to a novel benzoylurea derivative represented by the formula, ##STR1## its production and insecticides containing it as an active ingredient.
Abstract: Disclosed herein is an improved process for the preparation of polymethylene polyphenyl polyisocyanate by reacting phosgene with a corresponding polyamine, followed by removing residual phosgene from the reaction mixture, the improvement comprising removing the residual phosgene by contacting the reaction mixture which is maintained at 150 degrees Centigrade or lower, with an inert solvent vapor stream at a temperature which is sufficient to effect a substantially complete removal of the residual phosgene.
Type:
Grant
Filed:
May 15, 1991
Date of Patent:
August 4, 1992
Assignee:
Miles Inc.
Inventors:
Irvin Van Horn, Ralph W. Hodges, Jr., Susan M. Strausser
Abstract: Isocyanates are prepared by catalytic cracking or pyrolysis of an amide according to the following reaction: ##STR1## wherein R is an alkyl or aryl group having 1 to 20 carbon atoms, R.sub.1 is a lower alkyl group having 1 to 4 carbon atoms and x is a whole number from 1 to 3.
Abstract: Process for the preparation of asymmetrically substituted ureas, carbamates, thiocarbamates or substituted isocyanates by reaction of an adduct of isocyanic acid and a tertiary amine with a primary and secondary amine, an alcohol, a thiol or a compound having one or two non-cumulated olefinic double bonds.
Type:
Grant
Filed:
July 12, 1990
Date of Patent:
February 25, 1992
Assignee:
Chemie Linz Gesellschaft m.b.H.
Inventors:
Martin Mullner, Gerhard Stern, Erich Schulz, Markus Rossler
Abstract: A process for oxidizing an organic compound selected from an aliphatic, aromatic, aliphatic/aromatic, cycloaliphatic and heterocyclic alcohol, thiol, sulfide, aldehyde, amine, amide, ketone, acid, ether, ester, and organic compounds containing an activated carbon-carbon double bond, which process comprises contacting said organic compound dissolved in an organic solvent with a hypochlorous acid solution.
Abstract: The invention provides an improved method for obtaining optically active amines, carbamates, and isocyanates by thermal fragmentation of optically active ureas through refluxing the ureas in C.sub.3 -C.sub.7 alcohol solution with or without catalytic amounts of alkali metal.
Type:
Grant
Filed:
August 28, 1987
Date of Patent:
August 13, 1991
Assignee:
The United States of America as represented by the Department of Health & Human Services
Abstract: .alpha.-(4-isocyanatophenoxy)-.psi.-(4-isocyanato-3-methyl-phenoxy)-alkanes and mixtures thereof with the corresponding methyl-free and/or dimethyl substituted diisocyanates are made by phosgenating the corresponding diamine(s). These diisocyanates do not form a precipitate when reacted with a polyol and produce polyurethanes having outstanding properties.
Abstract: A process for preparing alkenoyl isocyanates of the formula: ##STR1## wherein R is a hydrogen atom or a lower alkyl group which comprises subjecting an oxazolinedione hydrohalide of the formula: ##STR2## wherein X is a halogen atom and R is as defined above to decomposition under an ordinary pressure, in the presence of a hydrogen halide-eliminating agent and/or in a liquid medium having a dielectric constant of not more than 4.
Abstract: A continuous, close-coupled method for making N-methyl carbamate pesticides which comprises contacting the methyl isocyanate in a vapor phase mixture containing methyl isocyanate and water with a selected oxime or phenol, said mixture being the reaction product formed by oxidizing monomethylformamide. An optional intermediate step for preparing the methyl isocyanate/water vapor phase reaction mixture for contact with the oxime or phenol is to remove therefrom a portion of the water without liquefying the methyl isocyanate by cooling the mixture to a temperature below the dew point of water but above the dew point of the methyl isocyanate.
Type:
Grant
Filed:
February 11, 1986
Date of Patent:
October 6, 1987
Assignee:
E. I. Du Pont de Nemours and Company
Inventors:
Charles T. Blaisdell, Walter J. Cordes, George E. Heinsohn, John F. Kook, John R. Kosak
Abstract: Water is fed together with formamide in vapor form in the production of isocyanates by silver-catalyzed oxidative dehydrogenation of formamides.
Abstract: The process in which methyl isocyanate is prepared by the oxidative dehydrogenation of monomethyl formamide is improved by performing the reaction in a quartz reactor.
Abstract: Isocyanates produced by vapor-phase catalytic oxidative dehydrogenation of corresponding N-substituted formamides are readily separated from by-product water by contacting the reaction mixture, in the vapor phase, with a cold brine mixture comprising water and about 25% to about 35% by weight of a salt or salts selected from the group consisting of NaCl, CaCl.sub.2, and MgCl.sub.2, the brine mixture having been maintained at a temperature between about 0.degree. C. and its freezing point prior to contact with the reaction mixture containing isocyanates.