Abstract: The invention describes a process for the preparation of N,o-substituted mono- and/or polyurethanes of formulaR.sup.1 [--NHCOOR.sup.2 ].sub.n,in whichR.sup.1 is an aliphatic, cycloaliphatic, aromatic, araliphatic, or heterocyclic radical, which may be substituted,R.sup.2 is an aliphatic, cycloaliphatic, or araliphatic radical which may be substituted with alkoxy or polyoxyalkylene groups, andn is a whole number from 1 to 5,through the reaction of N-substituted allophanates and/or polyallophanates with alcohols R.sup.2 OH in the presence or absence of catalysts at temperatures of at least 160.degree. C., preferably from 165.degree. to 250.degree. C.

Abstract: A process for the preparation of aliphatic, cycloaliphatic, arylaliphatic and aliphatic-cycloaliphatic di- and polyurethanes wherein primary aliphatic, cycloaliphatic, arylaliphatic or aliphatic-cycloaliphatic di- or polyamines are reacted with urea and a primary or secondary aliphatic alcohol at temperatures of above 190.degree. C. to 300.degree. C., following which ammonia and other by-products are separated from the aliphatic, cycloaliphatic, arylaliphatic or aliphatic-cycloaliphatic di- or polyurethane product.

Abstract: The invention describes a process for the preparation of N,o-substituted mono- and/or polyurethanes of formulaR.sup.1 [--NHCOOR.sup.2 ].sub.n,in whichR.sup.1 is an aliphatic, cycloaliphatic, aromatic, araliphatic, or heterocyclic radical, which may be substituted,R.sup.2 is an aliphatic, cycloaliphatic, or araliphatic radical which may be substituted with alkoxy or polyoxyalkylene groups, andis a whole number from 1 to 5,through the reaction of N-substituted allophanates and/or polyallophanates with alcohols R.sup.2 OH in the presence or absence of catalysts at temperatures of at least 160.degree. C., preferably from 165.degree. to 250.degree. C.

Abstract: Hexamethylene 1,6-diisocyanate and/or isomeric aliphatic diisocyanates where alkylene is of 6 carbon atoms, preferably 2-methylpentamethylene 1,5-diisocyanate and/or 2-ethyltetramethylene 1,4-diisocyanate, are prepared by a process wherein the corresponding dialkylurethanes are vaporized, without decomposition, at from 220.degree. to 300.degree. C., advantageously under reduced pressure, the dialkylurethane vapors are subjected to thermal cleavage under reduced pressure, preferably from 0.1 to 200 mbar, and at above 300.degree. C., preferably from 310.degree. to 480.degree. C. The cleavage products are fractionally condensed with the product obtained in the first condensation stage consisting predominantly of the diisocyanates, while that obtained in the second condensation stage is the alcohol.

Abstract: A method for the production of N-aryl substituted di- and polyurethanes in high yield, by the reaction of an aromatic di- or polyamine with urea and alcohol at high temperatures. The di- and polyurethanes thus produced have utility as isocyanate precursors.

Abstract: This invention discloses a non-phosgene process for the preparation of 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate by the reaction of the precursor diamine with urea and an aliphatic alcohol in the presence of a dialkyl carbonate and an alkyl carbonate. The intermediate diurethane is separated from starting materials and by-products and thermally cleaved to alcohol and diisocyanate which are separated by fractional condensation of the products from the vapor state. This process gives high yields of the desired diisocyanate and lends itself particularly to continuous processing.

Abstract: Hexamethylene diisocyanate and/or isomeric alkylene diisocyanates having 6 carbon atoms in the alkylene radical, preferably 2-methylpentamethylene 1,5-diisocyanate and/or 2-ethyltetramethylene 1,4-diisocyanate are prepared without the use of phosgene in a multiple-step process by means of(a) reacting hexamethylene 1,6-diamine and/or isomeric alkylene diamines having 6 carbon atoms in the alkylene radical with urea and alcohol in the presence of dialkyl carbonate and/or carbamic acid alkyl ester as well as, in some cases, catalysts to form hexamethylene 1,6-dialkylurethane and/or isomeric alkylene dialkylurethanes having 6 carbon atoms in the alkylene radical,(b) separation and return to reaction step (a) of alcohol, dialkyl carbonate, and/or carbamic acid alkyl ester from the reaction mixture(c) evaporation of the hexamethylene 1,6-dialkylurethane and/or isomeric alkylene dialkylurethanes having 6 carbon atoms in the alkylene radical,(d) cleavage of the vaporized diurethanes into hexamethylene diisocyanate an

Abstract: N- and O-substituted carbamates are prepared by reacting urea with an aminopropanol at 140.degree. C. or above. The compounds obtained by the novel process are useful starting materials for the preparation of textile finishing agents, stabilizers, plasticizers, dyes and crop protection agents.

Abstract: A process for the pyrolysis of mono-, di-, and polyurethanes to the corresponding mono-, di-, and polyisocyanates wherein the urethane to be cleaved is heated under pressure and sprayed through a nozzle into a pyrolysis chamber maintained at reduced pressure. The isocyanate and alcohol cleavage products are separated by fractional condensation.

Abstract: A process for the preparation of an aliphatic, cyclo-aliphatic, and/or aliphatic-cycloaliphatic di- and/or polyurethane comprising the steps ofA. reacting a primary aliphatic, cycloaliphatic, and/or aliphatic-cycloaliphatic di- and/or polyamine with a carbamate in the presence of alcohol at temperatures of 160.degree. C. to 300.degree. C., andB. separating the ammonia and other by-products from the aliphatic, cycloaliphatic, and/or aliphatic-cycloaliphatic di- and/or polyurethane.One or more catalysts may be added to the reactants to increase the reaction rate. The aliphatic, cycloaliphatic, and/or aliphatic-cycloaliphatic di- and/or polyurethanes produced are valuable end and intermediate products. They can be transferred into the corresponding isocyanates which can then be used for the preparation of polyurethanes.

Abstract: Organic isocyanates, preferably alkyl, mono-, di- and/or polyisocyanates or aryl-mono-, di- and/or polyisocyanates, are prepared by thermally cleaving the corresponding urethanes at temperatures of 175.degree. C. to 600.degree. C. in the presence of carbon, preferably in an agitated carbon bed or in a fluidized bed containing carbon.

Abstract: 1-Alkenyl isocyanates are prepared by reacting aldehydes with carbamates to give N-(1-alkenyl)-carbamates and splitting these compounds at elevated temperatures. The 1,2-unsaturated isocyanates obtained are valuable starting materials for the preparation of pest control agents, dyes, drugs, textile water repellents, detergents, plastics, bleaches and adhesives, since they possess an activated double bond or an activated .alpha.-carbon atom, in addition to a reactive isocyanate group.

Abstract: Carbonates are prepared by reacting carbamic acid esters with alcohols at above 140.degree. C., the ammonia formed being stripped from the reaction mixture during the reaction by passing an inert gas or vapor therethrough.The carbonates obtainable by the process of the invention are valuable starting materials for the preparation of dyes, crop protection agents and plastics.

Abstract: A process for the preparation of an aryl mono-, di-, and/or polyurethane comprising the steps of A. reacting a primary aromatic mono-, di-, and/or polyamine with an O-alkyl carbamate in the presence of an alcohol at temperatures greater than 160.degree. C., andB. separating the ammonia and other by-products from the aryl mono-, di-, and/or polyurethane.The reaction is preferably carried out in the presence of urea. The aryl mono-, di-, and/or polyurethanes produced are valuable end and intermediate products. They can be transferred into the corresponding isocyanates which can then be used for the preparation of polyurethanes.

Abstract: A process for the production of mixtures of diphenylmethane diisocyanates and polyphenyl polymethylene polyisocyanates comprising the steps ofA. reacting aniline and an O-alkyl carbamate to form N-phenylurethanes;B. isolating the N-phenylurethanes;C. condensing, in the presence of an acid, the N-phenylurethanes with formaldehyde or bifunctional compounds having the formulaX--CH.sub.2 --Xin which X stands for a RO--, RS-- or ROCO radical and R denotes an alkyl radical, to form mixtures of methylene bis(phenylurethanes) and polymethylene polyphenylurethanes;D. cleaving the mixtures of methylene bis(phenylurethanes) and polymethylene polyphenylurethanes at temperatures of 175.degree. C. to 600.degree. C.; andE. isolating the mixtures of diphenylmethane diisocyanates and polyphenyl polymethylene polyisocyanate resulting from step D.

Abstract: A process for making aryl isocyanates comprises thermally decomposing aryl urethanes at a temperature between 175.degree. C. and 600.degree. C. in the presence of a catalyst, present in the heterogeneous phase, said catalyst being a metal selected from the group consisting of zinc, aluminum, titanium, iron, chromium, cobalt and nickel.

Abstract: Isocyanates are prepared by thermal decomposition of oxalic acid ester amides at not less than 300.degree. C.The isocyanates obtainable by the process of the invention are valuable starting materials for the preparation of crop protection agents, pesticides, dyes, synthetic resins, plastics, textile waterproofing agents, detergents and adhesives.

Abstract: A process for the preparation of an aromatic urethane by the reaction in solution of an aromatic nitro compound or aromatic amine in the presence of an oxidation agent, with a hydroxyl compound and carbon monoxide in the presence of a noble metal catalyst, the improvement which comprises (a) treating the reaction solution, containing the noble metal catalyst, after the urethane formation is complete, with hydrogen (b) separating the noble metal in elementary form from the reaction solution, and (c) reusing the noble metal, together with a hydrohalic acid, as a catalyst.

Abstract: N-Aryloxazolidine-2,4-diones are prepared by reacting a nitrobenzene with a 2-hydroxycarboxylic acid ester and carbon monoxide in the presence of selenium and a basic compound under super-atmospheric pressure and at an elevated temperature.The N-aryloxazolidine-2,4-diones of the formula I, obtainable by the process of the invention are valuable active ingredients and starting materials for the preparation of crop protection agents, dyes and drugs.

Abstract: This invention pertains to a process for the preparation of an aromatic di- and/or polyisocyanate comprising the steps ofA. preparing an aromatic di- and/or polyurethane by1. reacting a primary aromatic di- and/or polyamine with an O-alkyl carbamate at temperatures greater than 100.degree. C.;2. separating the ammonia and other by-products from the aromatic di- and/or polyurethane;B. heating and the aromatic di- and/or polyurethane at temperatures of from 175.degree. C. to 600.degree. C.; andC. isolating the di- and/or polyisocyanate resulting from step B.