Abstract: A process for working up residues from the preparation of pyrrolidone and/or N-vinylpyrrolidone comprises subjecting the residues to a thermolysis.

Abstract: The invention describes a process for the isolation of pure N-vinylpyrrolidone from N-vinylpyrrolidone-containing crude products, comprising a single-stage or multistage crystallization process, which comprises passing the mother liquor from the first crystallization stage either to a distillative and/or extractive purification, or returning it to an N-vinylpyrrolidone-containing product stream of the preparation process.

Abstract: The invention describes a process for the isolation of pure N-vinylpyrrolidone from N-vinylpyrrolidone-containing crude products, comprising a single-stage or multistage crystallization process, which comprises passing the mother liquor from the first crystallization stage either to a distillative and/or extractive purification, or returning it to an N-vinylpyrrolidone-containing product stream of the preparation process.

Abstract: A process for working up residues from the preparation of pyrrolidone and/or N-vinylpyrrolidone comprises subjecting the residues to a thermolysis.

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: A process for vinylation of an organic acidic-hydrogen compound, which entails reacting an organic acidic-hydrogen compound with acetylene or an acetylene-containing gas under elevated pressure and at elevated temperature in the presence of a base, wherein reactor regions initiating decomposition of acetylene are treated with an effective amount of a chemically inert oil of medium viscosity.

Abstract: Process for carrying out gas/liquid reactions at from (-50.degree.) to 300.degree. C. and from 0.1 to 100 bar by carrying out the reaction in the absence of a continuous gas phase, and, as a special case, a process for the batchwise reaction of acetylene in the liquid phase at from 0.degree. to 300.degree. C. and from 2 to 30 bar, in which acetylene is introduced a) in the absence of a continuous gas phase and b) under isobaric conditions to a degree of saturation of from 5 to 100%.

Abstract: The preparation of monovinyl ethers of the general formula I ##STR1## in which A stands for a chemical bond or for a methylene or ethylene group, the radicals R.sup.1 and R.sup.2 independently stand for hydrogen, alkyl, cycloalkyl, or aryl groups or R.sup.1 and R.sup.2 together form a C.sub.3 -C.sub.5 alkylene bridging member, by the reaction of a diol of the general formula II ##STR2## in which the variables have the above meanings, with acetylene in the presence of a base, in which the reaction is carried out at 150.degree.-250.degree. C. under an acetylene partial pressure of 5-25 bar until 40-80% of the diol has been converted, at which point the reaction is stopped and the monovinyl ether of the formula I is isolated.

Abstract: In a process for purifying N-vinylpyrrolidone by crystallization in a crystallizer, those surfaces of the crystallizer from which crystals grow during the crystallization are covered with an N-vinylpyrrolidone seed layer before the crystallization.

Abstract: Reaction mixtures obtained in addition reactions of OH-- or NH-- carrying compounds with acetylene or propyne in the presence of alkali metal alcoholates or alkali metal amides are worked up by distilling off the vaporizable components from the reaction mixture in a thin-film evaporator. Before removal of the vaporizable components from the reaction mixture, a particularly defined polyether is added thereto.

Abstract: N-Vinyllactams of the general formula I ##STR1## where n is from 1 to 3, are prepared by a process which comprises reaction of a lactam of the general formula II ##STR2## where n is from 1 to 3, with from 10 to 90 percent by weight of an aqueous alkali metal hydroxide solution with distillation at from 50.degree. to 250.degree. C. and from 1 to 100 mbar and with a residence time of from 0.1 to 5 hours and subsequent reaction with acetylene at from 60.degree. to 250.degree. C. and from 1 to 100 bar.

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 preparing 3-(hydroxyphenyl)propionaldehydes of the formula I ##STR1## and, where appropriate, for preparing 3-(hydroxyphenyl)propanols of the formula II ##STR2## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each hydrogen, C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.20 -cycloalkyl, C.sub.4 -C.sub.20 -alkylcycloalkyl, C.sub.4 -C.sub.20 -cycloalkylalkyl or C.sub.5 -C.sub.20 -alkylcycloalkylalkyl,R.sup.3 and R.sup.4 are each aryl, C.sub.7 -C.sub.20 -aralkyl, heterocycloalkyl or C.sub.3 -C.sub.20 -heterocycloalkylalkyl, entailsa) reacting phenols of the formula III ##STR3## where R.sup.1 and R.sup.2 have the abovementioned meanings, with 3-hydroxypropionaldehydes of the formula IV ##STR4## where R.sup.3 and R.sup.4 have the abovementioned meanings, in the presence of a basic catalyst at from 90.degree. to 230.degree. C. and under from 0.01 to 50 bar and, where appropriate,b) treating the resulting 3-(hydroxyphenyl)propionaldehydes of the formula I ##STR5## where R.sup.1, R.sup.2, R.sup.3 and R.sup.

Abstract: A process for the preparation of 2,2-bis-hydroxymethyl-butanediol-(1,4) of formula I ##STR1## wherein 4-hydroxybutyraldehyde of formula II ##STR2## and/or 2-hydroxytetrahydrofuran of formula III ##STR3## is/are condensed with formaldehyde in the presence of a basic catalyst and the resulting reaction mixture is then catalytically hydrogenated, and 2,2-bis-hydroxymethyl-butanediol-(1,4) is isolated from the hydrogenation product.

Abstract: The invention provides a process for the preparation of a 4-halobenzyl alcohol of the formula ##STR1## where R.sup.1 is hydrogen, C.sub.1 - to C.sub.20 -alkyl, C.sub.2 - to C.sub.20 -alkoxyalkyl, C.sub.3 - to C.sub.20 -cycloalkyl, or C.sub.4 - to C.sub.30 -cycloalkylalkyl,R.sup.2 is C.sub.1 - to C.sub.20 -alkyl, C.sub.2 - to C.sub.20 -alkoxyalkyl, C.sub.3 - to C.sub.20 -cycloalkyl or C.sub.4 - to C.sub.30 -cycloalkylalkyl,X is halogen andm is 0 to 2,by reacting a haloaromatic carbonyl compound of the formula ##STR2## where R.sup.1, R.sup.2, X and m are as defined above, with hydrogen on a hydrogenation catalyst consisting essentially of copper oxide (I), copper oxide (II) and mixtures thereof in the presence of at least one primary, secondary or tertiary amine selected from the group consisting of acyclic, cyclic and heterocyclic aliphatic amines, in the presence or absence of an inert solvent, at from 50.degree. to 130.degree. C. and at from 10 to 200 bar.