Abstract: The invention relates to the production and purification of salts of 6,8-bis (amidiniumthio)octanoic acid, its enantiomers (+)-6,8-bis(amidiniumthio)octanoic acid and (-)-6,8-bis (amidiniumthio)octanoic acid and of the esters of these compounds as well as to their use to produce dihydrolipoic acid and .alpha.-lipoic acid.

Abstract: The invention relates to the production and purification of salts of 6,8-bis(amidiniumthio) octanoic acid, its enantiomers (+)-6,8-bis(amidiniumthio)octanoic acid and (-)-6,8-bis (amidiniumthio)octanoic acid and of the esters of these compounds as well as to their use to produce dihydrolipoic acid and .alpha.-lipoic acid.

Abstract: RS-thioctic acid with a novel morphology which is obtained by a recrystallization process.

Abstract: A process is described for the simultaneous production of 1,2- and 1,3-propanediol from glycerol. The process involves the reaction stages (a) dehydration of glycerol by feeding a gaseous glycerol-water mixture with 10 to 40 wt % glycerol at 250.degree. to 340.degree. C. over a solid catalyst with an H.sub.0 value (Hammett acidity function) of less than 2, preferably between -3 and -8.2, (b) hydration of the acrolein contained in the reaction mixture of stage (a), and (c) catalytic hydrogenation of the reaction mixture, containing 3-hydroxypropionaldehyde and hydroxyacetone, of stage (b). Two valuable products, namely 1,2- and 1,3-propanediol, can be obtained simultaneously and in high total yield from glycerol in a simple process.

Abstract: A process for the production of acrolein by dehydration of glycerol in the liquid phase or in the gaseous phase, in each case on acidic solid catalysts, is described. Compared with previously known processes, the space-time yield and catalyst service life may be surprisingly increased with higher selectivity by treating a glycerol-water mixture with a glycerol content of 10 to 40 wt. % at 180.degree. to 340.degree. C. (liquid phase) or at 250.degree. to 340.degree. C. (gaseous phase) on a solid catalyst with an H.sub.o value (Hammett acidity function) of less than +2, preferably less than -3.

Abstract: Optically active salts are disclosed of the formula (I): ##STR1## wherein Ac represents an acyl group, R.sup.1 hydrogen or methyl, R.sup.2 and R.sup.3 identical or different substitutes, preferably methyl. The salts can be obtained from the corresponding optically active carbonic acid and DL-3-cyano-2-hydroxypropyl trimethylammonium hydroxide. The diastereomeric salt pairs are easily split from one another and separated again, so that the process is suited for producing optically active 3-cyano-2-hydroxypropyl trimethylammonium salts.

Abstract: Synthesis of L-carnitine by chemical optical resolution of D,L-carnitine nitrile salts, where the D,L-carnitine nitrile salt is reacted with optically active N-acetylproline as the resolving agent in order to form the diastereomer salts after conversion to the hydroxide form, one of the two diastereomer salts is separated by fractional crystallization and the fraction containing mainly L-carnitine nitrile salt is treated with an optically inactive strong acid in order to split off the optically active N-acetylproline and then the resolving agent is separated and the resulting L-carnitine nitrile salt is saponified to L-carnitine. N-acetyl-L-proline is used as the resolving agent and the diastereomer (LL) salt is obtained in crystalline form in a high optical purity by fractional crystallization and the L-carnitine nitrile salt obtained after splitting off and separating N-acetyl-L-proline is used directly for saponification without further crystallization.

Abstract: Aqueous solutions of free, neutral .alpha.-amino acids are recovered from aqueous solutions of their alkali-metal salts. Two equally large rectifying columns filled with a strongly acidic cation exchanger in the H.sup.+ form are used, the discharge of the first column being connected to the head of the second column. The solution of the alkali-metal salt is at first delivered to the head of the first column, then the residual solution, reduced by the alkali-metal cations adsorbed in the exchanger, is displaced to the second column by means of the addition of water. A product-free forerun is first separated at the discharge of the second column and, when free .alpha.-amino acid begins to exit in the flow-off from the second column, the receiver is changed and the delivery of water to the head of the first column continues further until a mixed pH between 5 and 7 has been achieved in the receiver.

Abstract: The invention relates to the preparation of optically active salts of the general formula ##STR1## from which the corresponding optically active 3-chloro-2-hydroxypropyltrimethyl ammonium chloride can be obtained by treatment with mineral acid.The L(-) form of this compound is a valuable component for the synthesis of L(-) carnitine.

Abstract: A method of preparing m-trifluoromethylphenyl acetonitrile of the formula ##STR1## in which m-trifluoromethyl toluene is reacted with cyanogen chloride in the gas phase at 600.degree. to 750.degree. C.

Abstract: To produce thiosemicarbazide hydrazine is reacted with hydrogen cyanide and sulfur to form hydrazine thiocyanate, and this is then converted into the thiosemicarbazide at an elevated temperature. Advantageously, the reaction is carried out in a polar solvent.

Abstract: 2-Amino-5-mercapto-1,3,4-thiadiazoles can be produced in very high yields from thiosemicarbazides and carbon disulfide in aqueous phase by working in the presence of the corresponding ammonium salt of bis-2,5-mercapto-1,3,4-thiadiazole at a temperature above 40.degree. C. Preferably the process is carried out in the presence of the mother liquor from a previous reaction.

Abstract: There is provided a process for the production of .beta.-mercaptopropionic acid and its esters and nitriles by reacting the corresponding acrylic acid derivatives with trithiocarbonates in aqueous solution.

Abstract: Herbicidally active derivatives of the formula ##STR1## in which R represents methyl, ethyl or n-propyl.

Abstract: Caprolactones such as .epsilon.-caprolactone are stabilized against discoloration with dihydroxybenzenes such as hydroquinone or compounds of the formula ##STR1## in which R.sub.1 is alkyl of 1 to 8 carbon atoms, andR.sub.2 is hydrogen or alkyl of 1 to 8 carbon atoms.Even the presence of air is not detrimental.

Abstract: A process for the preparation of .epsilon.-caprolactone comprising:(a) reacting cyclohexanone with a solution of perpropionic acid in an organic solvent at a molar ratio of cyclohexanone;perpropionic acid of about 1.1-5:1 at a temperature of about 10.degree. to 80.degree. C. to form a reaction mixture consisting essentially of .epsilon.-caprolactone, propionic acid and organic solvent,(b) distilling the reaction mixture from (a) in a first distillation unit to obtain a distillate comprising the organic solvent and a distillation residue,(c) introducing the distillation residue from (b) at a point into a second distillation unit to obtain a distillate comprising propionic acid and unreacted cyclohexanone, removing from the second distillation unit, separately from one another and at a point below the point of introduction into the second distillation unit, .epsilon.

Abstract: There are produced carboxylic acid cyanides, e.g., acyl cyanides by reacting a carboxylic acid halide with an alkali cyanide or hydrogen cyanide in the presence of a copper (I) salt and a carboxylic acid nitrile. Especially advantageous are glutaric acid dinitrile and 2-methyl glutaric acid dinitrile.

Abstract: 4-amino-6-tert.butyl-3-mercapto-1,2,4-triazin-5-one of the formula ##STR1## is produced by reacting pivaloyl cyanide and isobutylene in the presence of acetic acid and sulfuric acid, hydrolyzing the reaction mixture in the presence of water and reacting the trimethyl pyruvic acid formed with thiocarbohydrazide. The triazinone is an important intermediate product in the synthesis of the known herbicide 4-amino-6-tert.butyl-3-methylmercapto-1,2,4-triazin-5-one.

Abstract: The invention relates to a process for the production of .epsilon.-caprolactone having a purity of 99.9% and increased color and storage stability which comprises feeding .epsilon.-caprolactone, which has been made by reacting cyclohexanone with a solution of a percarboxylic acid, into a first distillation unit, operating at 0.1 to 500 mbars and drawing off as the top product a mixture consisting of .epsilon.-caprolactone and lower-boiling impurities, feeding the bottom product of said first distillation unit into a second distillation unit, operating at 0.1 to 500 mbars and then drawing off the pure .epsilon.-caprolactone as the top product. The .epsilon.-caprolactone is useful as an intermediate for the production of known useful compounds such as polyesterols which are subsequently converted to polyurethanes.

Abstract: Compounds are prepared of the formula ##STR1## where R' is a t-alkyl group having 4 to 18 carbon atoms, preferably t-butyl, t-amyl or t-octyl and R is a straight or branched chain alkyl group with 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms or an alkyl group substituted with one or more phenyl group or a halogen atom, particularly a chlorine atom, or a cycloalkyl group with 3 to 8 carbon atoms, particularly cyclopropyl, which can be substituted by one or more 1 to 3 carbon atom alkyl groups or one or more halogen atoms, preferably chlorine, or phenyl or naphthyl or a five membered heterocyclic group or such phenyl, naphthyl or heterocyclic group substituted by halogen atoms, nitro groups, alkyl or alkoxy with 1 to 5 carbon atoms by condensing in acid medium an acyl cyanide of the formulaR--CO--CN (II)where R is as defined above with either(a) a tertiary alcohol of the formulaHO--R' (III)in which R' is as defined above, or preferably(b) an alkene of the formula ##STR2## where R.sub.1 and R.sub.