Abstract: Alcohols are prepared by the catalytic hydrogenation of the corresponding carbonyl compounds at elevated temperatures and at superatmospheric pressure in the liquid phase by a process in which the catalyst used contains copper on an SiO2-containing carrier in the presence or absence of one or more of the elements magnesium, barium, zinc and chromium.

Abstract: (Cyclo)aliphatic polyisocyanate compositions which have a long shelf life, are obtainable by phosgene-free methods, preferably by thermal cleavage of (cyclo)aliphatic polycarbamates, and, for stabilization, contain at least one primary stabilizer (2a), preferably a sterically hindered phenol and/or an aromatic amine, or at least one secondary stabilizer (2b), preferably an organic phosphite and/or a thioether, or at least one acidic stabilizer (2c), preferably a carboxylic acid, an acyl chloride, an inorganic acid, an inorganic acid chloride and/or a diester of phosphoric acid, or a stabilizer system comprising at least 2 of the stabilizers (2a) to (2c), a process for the preparation of the (cyclo)aliphatic polyisocyanate compositions and their preferred use for the preparation of isocyanurate-containing polyisocyanates.

Abstract: Aldehydes with a higher number of carbon atoms and high selection are prepared by reacting olefins, in particular from petrochemical refinery products, by a hydroformylation with aldol condensation using a mixed catalyst of rhodium-carbonyl-phosphines and Mannich catalyst.

Abstract: In a reactor for the thermal cleavage of mono- and polyfunctional carbamic esters into the corresponding isocyanates and the hydroxyl component in the liquid phase, the geometry of the reactor, defined by the degassing area in relation to the volume and the arrangement of the heating surfaces, permits cleavage in a two-phase mixture which has a volumetric gas content of more than 50%.

Abstract: The preparation of 2-substituted but-2-ene-1,4-dial-4-acetals of the formula I ##STR1## in which the substituents R.sup.1 to R.sup.4 stand for hydrogen or C.sub.1 -C.sub.6 aliphatic radicals, and R.sup.2 and R.sup.3 or R.sup.1 and R.sup.2 are in each case common members of an aliphatic 4-membered to 7-membered ring, which can contain a hetero atom, and R.sup.

Abstract: Hemiacetals of glyoxal monoacetals are useful as intermediates to prepare 2-substituted but-2-en-1,4-dial-4-acetals of the general formula I; ##STR1##

Abstract: Novel 2,2 -dialkylpentane-1,5-diisocyantes, 2,2-dialkylpentane-1,5-diurethanes and 2,2-dialkylpentane-1,5-dicarbamoyl chlorides of the formula ##STR1## where R.sup.1 and R.sup.2 are identical or different linear C.sub.1 -to C.sub.12 -alkyl, branched C.sub.3 - to C.sub.12 -alkyl, branched C.sub.2 - to C.sub.12 -alkenyl or branched C.sub.4 - to C.sub.12 -alkenyl,or R.sup.1 and R.sup.2 together are alkylene having from 4 to 7 carbon atoms, which is unsubstituted or substituted by from 1 to 5 C.sub.1 - to C.sub.4 -alkyl groups, and X is NCO, NH--CO.sub.2 R.sup.3, NHCO.sub.2 R.sup.4 or NHCOCl, where R.sup.3 and R.sup.4 are identical or different and are linear C.sub.1 - to C.sub.20 -alkyl, branched C.sub.3 - to C.sub.20 -alkyl or C.sub.5 - to C.sub.12 -cycloalkyl, are described.

Abstract: 2-Methyl-1,4-butanediol and 3-methyltetrahydrofuran are prepared by reacting a compound of the general formula I or II ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or C.sub.1 -C.sub.8 -alkyl and the formyl group of II may also be present as acetal with a C.sub.1 -C.sub.8 -alkanol, is reacted with hydrogen in the presence of copper or of a metal of groups 7 to 10 of the Periodical Table of elements or of a compound of these metals.

Abstract: A process for the preparation of 3-cyano-3,5,5-trimethylcyclohexanone by the reaction of isophorone with hydrogen cyanide in the presence of quaternary ammonium catalysts at temperatures ranging from 80.degree. to 180.degree. C. and pressures ranging from 0.5 to 20 bar, in which the ammonium catalysts used are salts of the general formula I ##STR1## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4 denote C.sub.1 -C.sub.18 alkyl, C.sub.5 -C.sub.8 cycloalkyl, aryl, C.sub.7 -C.sub.18 aralkyl or C.sub.2 -C.sub.18 hydroxyalkyl andX denotes HCO.sub.3 or ##STR2## with the proviso that R.sup.4 stands for C.sub.1 -C.sub.

Abstract: Polyisocyanates containing isocyanurate groups are prepared by a partial trimerization of (cyclo)aliphatic diisocyanates in the presence of at least one trimerization catalyst selected from the group consisting of tetraalkylammonium alkyl carbonates of the formula (I) ##STR1## (quaternary ammonioalkyl) carbonates having a betaine structure of the formula (II) ##STR2## and the preferred use of the polyisocyanates containing isocyanurate groups which are obtainable in this way is aspolyisocyanate component in polyurethane finishes.

Abstract: A process for the preparation of aminopropionitriles of the general formula I ##STR1## in which R denotes hydrogen or methyl, wherein ammonia is caused to react with an acrylonitrile of the general formula II ##STR2## In which the substituent has the aforementioned meanings, in a molar ratio of from 1:1 to 500:1 over a heterogenic catalyst at temperatures ranging from 40.degree. to 180.degree. C. and pressures ranging from 10 to 350 bar.

Abstract: Polyoxyalkylene glycols are prepared by a process in which tetrahydrofuran is polymerized with a total of not more than 95 mol %, based on the amount of tetrahydrofuran used, of one or more comonomers from the group consisting of the cyclic ethers and acetals in the absence of water and in the presence of a monohydric alcohol or of a monocarboxylic acid with the aid of an anhydrous heteropoly acid catalyst, and the polyoxyalkylene glycol is liberated from the resulting polyoxyalkylene glycol monoethers or polyoxyalkylene glycol monoesters by cleavage of the monoether or monoester bond.

Abstract: 1,1'-bis(3-aminopropyl)-2,2'-diimidazole of the formula I ##STR1## is prepared by a novel process in which 2,2'-diimidazole of the formula II ##STR2## is reacted with acrylonitrile of the formula III ##STR3## in the presence of basic catalysts at from 80.degree. to 150.degree. C., and hydrogenation is carried out with excess hydrogen in the presence of ammonia on catalysts which contain cobalt, nickel, ruthenium and/or noble metals at from 40.degree. to 200.degree. C. under from 10 to 200 bar.

Abstract: A multistep process for the continuous preparation of organic polyisocyanates, preferably aliphatic or cycloaliphatic diisocyanates, by reacting the corresponding organic polyamines with carbonic acid derivatives and alcohols to give monomeric polyurethanes and pyrolyzing the latter involves separating the resultant polyisocyanates and worthless residues in certain reaction steps and recycling the reusable by-products into earlier steps.

Abstract: 4-Acetoxystyrene of the formula I ##STR1## is prepared by a process in which a 1-(4-acetoxyphenyl)ethyl carboxylate of the formula II ##STR2## where R is C.sub.1 -C.sub.10 -alkyl, C.sub.3 -C.sub.6 -cycloalkyl, aryl or C.sub.7 -C.sub.10 -aralkyl, is converted in the presence of an acidic catalyst and of a polymerization inhibitor in an inert heat transfer medium at from 160.degree. to 250.degree. C. and from 0.1 to 300 mbar.

Abstract: A process for preparing neopentyl glycol hydroxypivalate by base-catalyzed disproportionation of hydroxypivalaldehyde, wherein the reaction is carried out in the presence of a readily water-soluble alkaline earth metal salt and of an alkali metal hydroxide.

Abstract: A process for the preparation of 3-aminomethyl-3,5,5-trimethyl-cyclohexylamine from 3-cyano-3,5,5-trimethyl-cyclohexanone, wherein the following stages are carried out in discrete reaction chambers:a) the 3-cyano-3,5,5-trimethyl-cyclohexanone is reacted in a first reaction chamber with excess ammonia over an acidic metal oxide catalyst at a temperature of from 20.degree. to 150.degree. C. and a pressure of from 15 to 500 bar, andb) in a second reaction chamber, the reaction product from stage a) is hydrogenated with hydrogen at a temperature of from 60.degree. to 150.degree. C. and a pressure of from 50 to 300 bar in the presence of excess ammonia over a catalyst containing cobalt, nickel, ruthenium, and/or some other noble metal, which catalyst optionally contains a basic component or is supported by neutral or basic supporting material.

Abstract: A process for preparing 5-cyanovaleramide by reacting adiponitrile with water at from 50.degree. to 200.degree. C. in the presence of a supported unionized-copper catalyst comprises employing from 1 to 15 mol of water per mole of adiponitrile and a residence time of from 5 to 60 minutes.

Abstract: Process for preparing a pentane-1,5-diamine of the formula ##STR1## where R.sup.1 represents a variety of organic radicals including alkyl which can bear substituents such as hydroxyl, halogen, alkoxy, carbalkoxy, carboxyl, alkylamino, cycloalkyl or aryl, andR.sup.2 and R.sup.3 independently of one another, represent hydrogen or have the same meanings as R.sup.1 or together are a C.sub.4 -C.sub.7 -alkylene chain which is unsubstituted or substituted by one to five C.sub.1 -C.sub.4 -alkyl groups,which comprises:(a) reacting a .gamma.-cyanoketone of the formula ##STR2## where R.sup.1, R.sup.2 and R.sup.3 have the meanings given above, with excess ammonia in a first reaction space on an acidic heterogeneous catalyst at 20.degree.-150.degree. C. and 15-500 bar, and(b) hydrogenating the resulting reaction product in a second separate reaction space in the presence of excess ammonia on a cobalt, nickel or noble metal catalyst at 50.degree.-180.degree. C. and 30-500 bar.

Abstract: 3-Aminopropionitriles of the general formula I ##STR1## where R.sup.1,R.sup.2,R.sup.3,R.sup.4 and R.sup.5 independently of one another are each hydrogen, C.sub.1 -C.sub.20 -alkyl, C.sub.1 -C.sub.8 -aminoalkyl, C.sub.1 -C.sub.8 -cyanoalkyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.7 -C.sub.20 -aralkyl or aryl,are prepared by a process in which an amine of the general formula II ##STR2## is reacted with an acrylonitrile of the general formula III ##STR3## where the substituents have the abovementioned meanings, in a molar ratio of from 0.9:1 to 100:1 over a heterogeneous catalyst at from 40.degree. to 200.degree. C. and from 1 to 350 bar.