Abstract: The preparation of 2,3-dialkoxypropanals of the general formula I ##STR1## in which R.sup.1 and R.sup.2 denote C.sub.1 -C.sub.8 -alkyl or C.sub.5 - or C.sub.6 -cycloalkyl which may or may not bear substituents which are inert under the conditions of the reaction, wherein a 1,2-dialkoxy ethene of the general formula IIR.sup.1 O--HC.dbd.CH--OR.sup.2 (II)is reacted with carbon monoxide and hydrogen in the presence of a rhodium-containing catalyst.

Abstract: Hydroxylamine derivatives have the general formula IAryl--A--O--B IwhereAryl is an unsubstituted or substituted, mononuclear or binuclear, isocyclic radical;A is a 1,4-butenylene group of the general formulae IIa or IIb ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are each hydrogen, halogen, C.sub.1 -C.sub.6 -alkyl or C.sub.1 -C.sub.6 -alkenyl;B is NH.sub.2 or a dicarboximide group of the general formula III ##STR2## where Z is unsubstituted or substituted phenylene, naphthylene, pyridinylene, cyclopentylene, cyclohexylene, cyclohexenylene, C.sub.2 -C.sub.4 -alkenylene or C.sub.2 -C.sub.4 -alkylene. The dicarboximides are intermediates for the compounds wherein B is NH.sub.2. The latter are used in synthesizing herbicidal compounds.

Abstract: A process for the preparation of benzaldehyde dialkyl acetals of the general formula ##STR1## where R.sup.1 is alkyl of 1 to 6 carbon atoms, R.sup.2, R.sup.3 and R.sup.4 are hydrogen or halogen, straight-chain, branched or cyclic hydrocarbon radicals or alkoxy, acyloxy, aryloxy or aralkoxy, and n is 1 or 2, in which benzyl derivatives of the general formula ##STR2## where R.sup.2, R.sup.3, R.sup.4 and n have the abovementioned meanings, R.sup.5 is hydrogen or R.sup.6 --CO--, and R.sup.6 is hydrogen or alkyl of 1 to 6 carbon atoms, are anodically oxidized in the presence of an alcohol of the formula R.sup.1 --OH where R.sup.1 has the abovementioned meaning.

Abstract: A process for preparing .alpha.-formylamino nitriles of the formula Ia ##STR1## and Ib ##STR2## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and each is hydrogen or unsubstituted or substituted, with substituents which are inert under the reaction conditions, aliphatic or heteroaliphatic radicals with 1 to 10, cycloaliphatic or heterocycloaliphatic radicals with 3 to 6, araliphatic radicals with 7 to 12, heteroaraliphatic radicals with 4 to 12, aromatic radicals with 6 to 10 or heteroarometic radicals with 3 to 10 carbon atoms, with the priviso that at least one of R.sup.1 and R.sup.2 or R.sup.3 and R.sup.4 is hydrogen, comprises reacting an iminodiacetonitrile of the formula II ##STR3## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 have the abovementioned meanings, with formamide of the formula III ##STR4## in the presence of formic acid or with a compound which provides formic acid, in the presence of acids.

Abstract: A method of isomerizing propargyl alcohol to acrolein, wherein propargyl alcohol is rearranged in the gas phase at a temperature of from 300.degree. to 550.degree. C. and a pressure of from 0.01 to 50 bar and in contact with a heterogeneous catalyst containing alkaline-reacting metal ions, and the use of propargyl alcohol as a depot substance for the liberation of acrolein.

Abstract: A process for preparing .alpha.-formylamino nitriles of the formula I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen or unsubstituted or substituted, with substituents which are inert under the reaction conditions, aliphatic or heteroaliphatic radicals with 1 to 10, cycloaliphatic or heterocycloaliphatic radicals with 3 to 6, araliphatic radicals with 7 to 12, heteroaraliphatic radicals with 4 to 12, aromatic radicals with 6 to 10 or heteroaromatic radicals with 3 to 10 carbon atoms, by reacting cyanohydrins of the formula II ##STR2## with the formamide III ##STR3## in the presence of acids, entails adding at least one ammonium salt to the reaction mixture.

Abstract: A process for the preparation of 1,4-butanediol by catalytically hydrogenating maleic anhydride in the presence of an alcohol, at elevated temperature and elevated pressure and with the aid of a cobalt-containing catalyst comprises partially hydrogenating the reaction mixture in a first hydrogenation step at from 100.degree. to 200.degree. C. and at from 30 to 200 bar and subsequently post-hydrogenating the product of this first hydrogenation step, without further work-up at higher temperature and pressure than in the first hydrogenation step, in a second hydrogenation step at from 200.degree. to 300.degree. C. and at from 200 to 350 bar.

Abstract: 4-alkoxy-2-hydroxybenzophenone-5-sulfonic acids of the general formula I ##STR1## where R.sup.1 is C.sub.1 -C.sub.20 -alkyl which is unsubstituted or substituted by halogen, cyanao, hydroxyl, C.sub.1 -C.sub.20 -alkoxy, C.sub.2 -C.sub.20 -alkoxycarbonyl, acyloxy and/or phenyl which is unsubstituted or substituted by C.sub.1 -c.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and/or halogen, R.sup.2 and R.sup.3 independently of one another are each hydrogen, halogen, C.sub.1 -C.sub.12 -alkyl, C.sub.1 -C.sub.12 -alkoxy, C.sub.1 -C.sub.4 -haloalkyl, C.sub.3 -C.sub.8 -cycloalkyl, C.sub.4 -C.sub.12 -cycloalkylalkyl, cyano, hydroxyl or hydroxyethyl or are each phenoxy, C.sub.7 -C.sub.10 -phenalkyl or phenyl which is unsubstituted or substituted by C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy and/or halogen, and R.sup.4 is hydrogen or sulfo, are prepared by reacting a 4-alkoxy-2-hydroxybenzophenone of the general formula II ##STR2## with chlorosulfonic acid at from -20.degree. to +100.degree. C.

Abstract: A process for the preparation of bis(4-hydroxyphenyl) sulfone by reacting phenol with sulfuric acid at a temperature of from 140.degree. to 230.degree. C., wherein the sulfuric acid is metered in to the phenol only after the reaction temperature has been reached, the phenol and sulfuric acid are used in a molar ratio of from 1:1 to 25:1 and the reaction is carried out in the absence of an inert solvent.

Abstract: A process for preparing 1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene of the formula I ##STR1## comprises reacting p-cymene of the formula II ##STR2## with a hexene of the formula IIIa, IIIb and/or IIIc ##STR3## in the presence of a catalytic amount of aluminum halide and a catalytic amount of a triphenylmethyl compound of the formula IV ##STR4## wherein R.sup.1, R.sup.2 and R.sup.3 are each, independently of one another, hydrogen, C.sub.1 -C.sub.4 -alkyl, nitro or halogen and X is hydrogen or halogen.

Abstract: Formylcyclopropane (I) ##STR1## is prepared by cyclization of 4-chlorobutanal by means of an aqueous mineral base by a method in which the reaction is carried out at 50.degree.-150.degree. C. in a liquid two-phase system consisting of an aqueous phase and a water-immiscible organic phase, and the formylcyclopropane is removed continuously from the reaction mixture.

Abstract: 1-hydroxy-1,2,4-traizoles have the general formula I ##STR1## where R.sup.1 and R.sup.2 are singly independently of the other hydrogen, alkyl, halogen or substituted or unsubstituted aryl or together an alkylene chain.

Abstract: 4-Chloropyrazoles of the general formula I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each independently of the others hydrogen or a radical which is inert under the reaction conditions, are prepared by reacting pyrazoles of the general formula II ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are each as defined above, with 0.95-10 equivalents of hypochloric acid, or salts thereof, in the substantial absence of any carboxylic acid.

Abstract: Octadienols are prepared by reacting 1,3-butadiene with water in the presence of a catalyst system comprising a palladium compound, a triorganophosphorus compound and carbon dioxide and in the additional presence of a triorganophosphine oxide.

Abstract: Carbonyl halides I ##STR1## where R.sup.1 is H, alkyl, cycloalkyl, haloalkyl or halocycloalkyl,R.sup.2 and R.sup.3 are each alkyl, cycloalkyl, haloalkyl or halocycloalkyl and may furthermore be bonded to one another to form a 5-membered to 7-membered ring andis halogen,are prepared by reacting an alkyl halide II ##STR2## with carbon monoxide under superatmospheric pressure in the presence of a catalytic amount ofa) aluminum bromide and in the presence or absence of a solvent orb) aluminum chloride or bromide and in the presence of a halohydrocarbon and a carbonyl halide of the formula IIIR.sup.4 --CH.sub.2 --CO--Hal (III)where R.sup.4 is hydrogen or C.sub.1 -C.sub.4 -alkyl and Hal is halogen.

Abstract: A catalyst for the hydrogenation of unsaturated aliphatic compounds having a content of 20-70% w/w of nickel oxide, 25-45% w/w of zirconium oxide and 5-40% w/w of copper oxide, based on the oxidic, unreduced catalyst.

Abstract: A process for the preparation of 2,5-dihydrofurans of the general formula I ##STR1## where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are identical or different and are hydrogen or C.sub.1 -C.sub.4 -alkyl, by the catalytic rearrangement of 3,4-epoxy-1-butenes of the general formula II ##STR2## comprises the rearrangement being catalyzed by a system which contains components A, B and C, at from 60.degree. to 200.degree. C., whereA is a halide of an alkali metal or alkaline earth metal or an onium halide,B is an organic solubilizer for component A, andC is a Lewis acid or elemental iodine,with the proviso that at least one of components A or C is an iodide. 2,5-Dihydrofurans are intermediates for the well known tetrahydrofurans which are used as solvents, e.g. for polyvinyl chloride, polyvinylidene chloride, and other difficultly soluble organic materials, and are also used as monomers for the preparation of polytetrahydrofurans.

Abstract: Polyethercarboxylic esters of the formula ##STR1## where Alk is alkyl of 1 to 8 carbon atoms, R is hydrogen or methyl and n is from 3 to 70.

Abstract: An evaluation unit accurately measures the elapsed time between two events. The two events mark the start and stop points of a switching device, such as a motor-operated valve, as it is switching between a first state and a second state. This elapsed time, when compared to a base-line elapsed time or a previously measured elapsed time, provides an indication as to whether the performance of the device has degraded to the point where maintenance or replacement of the switching devices required. The unit includes electro-optical means for individually sensing the occurrence of each event, logic means for selecting the occurrence of either event as the starting or stopping point for the time measurement, and a timing circuit for performing and displaying the time measurement.

Abstract: A method of separating .gamma.-butyrolactone from a mixture containing ethanol, tetrahydrofuran, water, n-butanol, 1,4-butanediol, diethyl succinate and .gamma.-butyrolactone, by distillation in vacuum columns.