Abstract: The invention relates to a method for the continuous extraction of lactic acid from an aqueous suspension containing solids. According to said method, the aqueous suspension containing solids is brought into contact, in a counter-current, with an organic solvent that is partially miscible with water, in a column provided with filling agents which have a surface consisting of hydrophobic material, in such a way as to form an aqueous phase and an organic phase, such that the organic phase is guided as a dispersed phase in a section of the column comprising filling agents.

Abstract: A process for removing impurities from 3-(2′-acetoxyethyl)dihydro-2(3H)furanone (I), where the 3-(2′-acetoxyethyl)dihydro-2(3H)furanone containing the undesirable impurities is initially prepared in a manner known per se by acetylation of 3-(2′-hydroxyethyl)dihydro-2(3H)furanone and the resulting product is subsequently subjected to a distillation or rectification, includes carrying out the distillation or rectification in a plurality of steps, where high-boiling impurities are removed in a first step, the product which is drawn off via the top is subsequently subjected to at least one further step in which low-boilers and intermediate boilers are drawn off via the top and the desired pure I is obtained as bottom product.

Abstract: A process for the preparation of &agr;-chloromethylene-triorganylphosphorane derivatives I (radicals R are C-organic substituents and A stands for CN or CO-B where B is a C-organic or O-organic radical which is inert under chlorination conditions) by chlorination of phosphoranes II with chlorine, wherein the chlorination is carried out in the presence of a mineral base as hydrogen chloride acceptor and the chlorine and base are fed to the reaction mixture concurrently but separately at the rates at which they are consumed. The reaction products I are important intermediates for plant protectants.

Abstract: The manufacture of 5-dichloroacetyl-3,3,6-trimethyl-9-oxo-1,5-diazabicyclo?4.3.0!-nonane I by the reaction of 3,3,6-trimethyl-9-oxo-1,5-diaza-bicyclo?4.3.0!nonane II with dichloroacetyl chloride in the presence of a solvent and a base, whereina) this reaction is carried out in a two-phase system comprising a virtually water-insoluble organic solvent and water, and sodium or potassium hydroxide acting as the base is metered in at a rate corresponding to the rate of consumption of the dichloroacetyl chloride such that the aqueous phase exhibits a pH of from 7 to 9, andb) the resulting product is separated.

Abstract: .alpha.,.beta.-Unsaturated ketones of the general formula I ##STR1## where R is an organic radical, are prepared by reacting a corresponding aldehyde R--CHO with acetoacetic acid or one of its salts in the presence of an amine in a two-phase reaction mixture by a process in which the reaction is carried out at a pH of from 6 to 8 in the presence of a catalytic amount of a primary amine.

Abstract: 3-(3,4,5,6-tetrahydrophthalimido)cinnamic esters I ##STR1## (R.sup.1 =H, halogen; R.sup.2, R.sup.3 =halogen; R.sup.4 =C-organic radical, R.sup.5 =H, CH.sub.3) are prepared by reducing 3-nitrocinnamic esters II ##STR2## with hydrogen in the presence of a catalyst and condensing the resulting 3-aminocinnamic esters III ##STR3## with a 3,4,5,6-tetrahydrophthalic anhydride IV ##STR4## and are valuable active ingredients in crop protection.

Abstract: Purification of 7-chloroquinoline-8-carboxylic acids I ##STR1## (X=H, halogen, lower alkyl group) by recrystallization from lower alcohols which are miscible with water, by carrying the recrystallization in the presence of small amounts of a base.The quinolinecarboxylic acids I are valuable crop protection agents.

Abstract: A process for the preparation of cyclohexanedione derivatives of the general formula I ##STR1## where R.sup.1 is C.sub.2 -C.sub.8 -alkyl, C.sub.2 -C.sub.8 -alkenyl, C.sub.3 -C.sub.12 -cycloalkyl, C.sub.5 -C.sub.12 -cycloalkyl with 0-4 olefinically unsaturated bonds, C.sub.2 -C.sub.8 -alkylthioalkyl, C.sub.6 -C.sub.12 -bicycloalkyl with 0-3 olefinically unsaturated bonds, unsubstituted or substituted aryl or hetaryl, or a heterocyclic radical of 4 to 7 atoms of which not more than 3 may be hetero-atoms chosen from O, S and N, the radical being saturated or olefinically unsaturated, by reacting an .alpha.,.beta.-unsaturated ketone (II) with a dialkyl malonate in the presence of a base to give the alkoxycarbonylcyclohexenolone or its salt (III) ##STR2## and acylation, hydrolysis and decarboxylation of (III), wherein the .alpha.,.beta.

Abstract: 2-chloro-5-nitrobenzaldehyde or an acetal thereof is isolated from a mixture of isomers thereof at a temperature of from -10.degree. to +140.degree. C., by suspending the mixture of isomers in a solvent or solvent mixture.

Abstract: A process for the preparation of cyclohexanedione derivatives of the general formula I ##STR1## where R.sup.1 is C.sub.2 -C.sub.8 -alkyl, C.sub.2 -C.sub.8 -alkenyl, C.sub.3 -C.sub.12 -cycloalkyl, C.sub.5 -C.sub.12 -cycloalkyl with 0-4 olefinically unsaturated bonds, C.sub.2 -C.sub.8 -alkylthioalkyl, C.sub.6 -C.sub.12 -bicycloalkyl with 0-3 olefinically unsaturated bonds, unsubstituted or substituted aryl or hetaryl, or a heterocyclic radical of 4 to 7 atoms of which not more than 3 may be hetero-atoms chosen from O, S and N, the radical being saturated or olefinically unsaturated, by reacting an .alpha.,.beta.-unsaturated ketone (II) with a dialkyl malonate in the presence of a base to give the alkoxycarbonylcyclohexenolone or its salt (III) ##STR2## and acylation, hydrolysis and decarboxylation of (III), wherein the .alpha.,.beta.

Abstract: A batchwise or continuous process for separating water from a mixture of water and 1-methoxy-2-propanol by passing a heated mixture in liquid or gaseous form over a hydrophilic membrane which is selective to the passage of water.

Abstract: A process for the preparation of N-phenyl(pyridyl)sulfonyldiamides by reacting a 2-aminobenzoic acid (nicotinic acid) derivative with sulfur trioxide, chlorosulfonic acid or an adduct of sulfur trioxide with a tertiary amine in the presence of a diluent and of a tertiary amine, and reacting the resulting sulfamate with a primary amine and a phosphorus halide, or by reacting a 2-aminobenzoic acid (nicotinic acid) derivatives with an N-alkyl(cycloalkyl)sulfamic acid or a salt of this acid in the presence of a diluent and of a phosphorus halide.

Abstract: Pyridazinone derivatives of the formula ##STR1## where R.sup.1 is alkyl, alkenyl, cycloalkyl or unsubstituted or substituted phenyl, R.sup.2 is chlorine or bromine, R.sup.3 is hydrogen, alkyl, cycloalkyl or unsubstituted or substituted phenyl and X is SO or SO.sub.2, with the proviso that R.sup.1 is not methyl when X is SO.sub.2, R.sup.2 is chlorine and R.sup.3 is phenyl, and fungicides containing these compounds.

Abstract: O-(1-Methoxy-2-chloro)ethoxyphenyl N-methylcarbamate is prepared by reacting pyrocatechol carbonate with methylamine and then reacting the resulting pyrocatechol monomethylcarbamate with 1,2-dichloroethyl methyl ether in the presence of a secondary amine.

Abstract: Sterically pure .beta.-triazolyl carbinols of the general structure ##STR1## where R is not hydrogen, in particular the R*, S*-diastereomer, are obtained by diastereoselective reduction of the corresponding .alpha.-triazolylketone with a complex hydride which reduces ketones to alcohols, in the presence of a Lewis acid in a non-polar solvent.

Abstract: 5,6-Dihydro-2H-thiopyran-3-carboxaldehydes of the formula ##STR1## where R denotes hydrogen or methyl, are prepared by a method in which acrolein or crotonaldehyde is reacted with hydrogen sulfide in a mineral oil whose boiling point is higher than those of the starting materials and of the end product, and the 5,6-dihydro-2H-thiopyran-3-carboxaldehyde is obtained by distillation. These aldehydes are important intermediates for the preparation of some crop protection agents.

Abstract: 3-Formyltetrahydrothiopyrans are prepared by hydrogenating a 3-formyl-5,6-dihydro-2H-thiopyran in the presence of a catalyst containing nickel, cobalt, platinum, copper and/or silver; if necessary, the 3-formyl-5,6-dihydro-2H-thiopyrans are prepared by converting bis-(.beta.-formylethyl) sulfides and/or 3-formyl-4-hydroxytetrahydrothiopyrans in the presence of an acidic catalyst, and, if required, these bis-(.beta.-formylethyl) sulfides and/or 3-formyl-4-hydroxytetrahydrothiopyrans are prepared by reacting an acrolein with hydrogen sulfide (a) in the presence of a basic catalyst and of methylene chloride, aromatic hydrocarbons and/or 1,1,2-trichloroethane as solvents, and/or (b) in the presence of a carboxamide.The compounds obtainable by the process according to the invention are useful starting materials for the preparation of dyes, drugs and pesticides.

Abstract: Azole compounds of the formula ##STR1## where V is oxygen or sulfur, X is hydrogen, halogen, alkyl, alkoxy, trifluoromethyl, phenyl or phenoxy, m is an integer from 1 to 5, W is an olefin group which is unsubstituted or substituted, or is alkynyl, Z is CH or N, and Y is C.dbd.O or CR.sup.3 OR.sup.4, where R.sup.3 is hydrogen, alkyl, alkenyl or alkynyl, and R.sup.4 is hydrogen, alkyl, alkenyl, alkynyl or alkanoyl, and their plant-tolerated addition salts with acids and metal complexes, and fungicides which contain these compounds.

Abstract: Aniline derivatives of the formula ##STR1## where R.sup.1, Y, A, Z and n have the meanings given in the description, are used for controlling undesirable plant growth.

Abstract: Pyrocatechol methylcarbamate is prepared by reacting pyrocatechol carbonate with methylamine in the presence of a tertiary amine and, preferably, a solvent.