Abstract: The invention concerns a method for preparing acrolein from glycerol or glycerine, wherein dehydration of the glycerol or glycerine is achieved in the presence of a catalyst based on zirconium oxide and which active phase consists in at least a) a silicon oxide, a zirconium oxide and at least one metal M oxide, said metal being selected from tungsten, cerium, manganese, niobium, tantalum, vanadium and titanium, b) a titanium oxide, a zirconium oxide and at least one metal M oxide, said metal being selected from tungsten, cerium, manganese, niobium, tantalum, vanadium and silicon. This method can be used for making 3-(methylthio)propionic aldehyde MMP, 2-hydroxy-4-,methylthiobutyronitrile HMTBN, methionine and its analogs.

Abstract: A process for preparing EDDN and/or EDMN by conversion of FA, HCN and EDA, the reaction being effected in the presence of water, wherein the reaction mixture from the conversion of EDA, HCN and FA is cooled after leaving the reactor.

Abstract: A process for preparing ethylenediaminediacetonitrile (EDDN) and/or ethylenediamine-monoacetonitrile (EDMN) by conversion of formaldehyde (FA), hydrogen cyanide (HCN) and ethylenediamine (EDA), which comprises using stabilizer-free HCN, or HCN which has been stabilized with an organic acid, in the process.

Abstract: A process (10) for at least partially removing hydrogen cyanide from synthesis gas includes feeding a synthesis gas (30) containing hydrogen cyanide to a gas-liquid contacting stage (18) and, in the gas-liquid contacting stage (18), contacting the synthesis gas with an aqueous washing solution (36) comprising at least one dissolved metal salt, with metal cations of the metal salt being capable of forming metal cyanide complexes and/or metal cyanide precipitates, and weak acid anions of the metal salt serving to buffer the pH of the washing solution in a range between 6 and 10. Hydrogen cyanide is washed from the synthesis gas by the washing solution to form a treated synthesis gas (38) and a spent washing solution (40). From time to time or continuously, at least a portion of the spent washing solution is withdrawn from the gas-liquid contacting stage. The treated synthesis gas (38) is also withdrawn from the gas-liquid contacting stage.

Abstract: Dicyanatochalcones of general formula: wherein R1 to R8, independent of one another, represent hydrogen, C1-4-alkyl, C1-4-alkoxy or halogen. The compounds can be produced from corresponding dicyanatochalcones by reacting them with chlorine cyanide or bromine cyanide and with a tertiary amine. The compounds are suited for producing polytriazine resins exhibiting good mechanical properties, a low dielectric constant and a good behavior in fire.

Abstract: A process for cyanating an aldehyde is provided.

Abstract: The present invention relates to a process for preparing a colour-stable, aqueous dimethylaminoacetonitrile solution from a formaldehyde source, dimethylamine and hydrocyanic acid, wherein the reaction mixture contains 2,4-diamino-6-phenyl-1,3,5-triazine (benzoguanamine) in a concentration of from 0.001 to 5% by weight, based on formaldehyde, prior to the reaction and the starting substances are used stoichiometrically or in a ratio of 0.98-1.02 mol of formaldehyde and 0.95-1.10 mol of dimethylamine per mol of hydrocyanic acid. The resulting product remains colour-stable without a further purification step even after prolonged storage.

Abstract: The present invention relates to a process for preparing optically active cyanohydrins of the formula (II), 1

Abstract: The present invention relates to a process for reacting &agr;-aminoaldehyde derivatives having a sterically bulky amino group which are commercially available with a metal cyanide in the presence of an acid chloride, an acid anhydride or the like to synthesize 3-amino-2-hydroxybutyronitrile derivatives in high yields and high erythro selectivity. When optically active &agr;-aminoaldehyde derivatives are used, racemization hardly occurs during the reaction, and the desired products are obtained in high optical purity.

Abstract: A synthesis is described for intermediates which are readily amenable to the large scale preparation of hydroxyethylurea-based chiral HIV protease inhibitors. The method includes forming a diastereoselective epoxide or cyanohydrin from a chiral alpha amino aldehyde.

Abstract: E-oxime ethers of phenylglyoxylic esters of the formula I ##STR1## where X and Y are each halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or trifluoromethyl;m is an integer from 0 to 4;n is an integer from 0 to 3;are prepared.

Abstract: Process for the preparation of .alpha.-acetoxy-.alpha.-methyl-N,N'-diacetylmalonamide wherein hydrocyanic acid or a cyanide is reacted in a first step with acetic anhydride and then in a second step the reaction mixture so obtained is treated with acetic acid in the presence of an acid catalyst, wherein the first step is carried out in the presence of a catalyst based on anion exchange resins in which the functional groups are quaternary ammonium or tertiary amine, such .alpha.-acetoxy-.alpha.-methyl-N,N'-diacetylmalonamides being very useful as activators in bleaching and cleaning compositions which are thus active at lower temperatures.

Abstract: The present invention relates to a novel process for the preparation of insecticidally active esters of the general formula (I) ##STR1## wherein R.sub.1 and R.sub.2 are the same or diferent from each other and represent a hydrogen or a halogen atom; R.sub.3 represents ##STR2## (wherein R.sub.4 and R.sub.5 represent a chlorine or bromine atom or a methyl group when R.sub.4 is identical to R.sub.5, but R.sub.4 represents a chlorine or bromine atom or a methyl group and R.sub.5 represents a trifluoromethyl group when R.sub.4 is different from R.sub.5, and R.sub.6 represents a halogen atom or a difluoromethoxy group); and R.sub.8 represents a hydrogen or a cyano group.The characteristic of the present invention is a one-step procedure comprising directly condensing an organic acid, an aldehyde (and a water-soluble cyanide) in the presence of a phase transfer catalyst and a water-soluble inorganic base by the use of a sulphonyl compound as a condensing reagent.

Abstract: A one step process for the preparation of certain cyanomethyl carboxylates is disclosed which comprises reacting an appropriate acyl compound with a water soluble metal cyanide such as sodium cyanide or potassium cyanide and an aldehyde such as formaldehyde, acetaldehyde, or benzaldehyde. Also disclosed is a method for inhibiting bacteria by contacting said bacteria or habitat thereof with an effective amount of an antibacterial cyanomethyl carboxylate.

Abstract: An alpha-arylacrylonitrile is prepared by reacting an aryl ketone having a removable hydrogen alpha to the carbonyl group with a cyanide ion source which is free of radicals that would stabilize a cyanohydrin corresponding to the aryl ketone and with a Lewis acid in the presence of an activating amount of water and/or HCl and preferably in the presence of a solvent. In a preferred embodiment, the aryl ketone is a tetralone, the cyanide ion source is sodium cyanide, the Lewis acid is aluminum chloride, and the product is a 1-cyano-3,4-dihydronaphthalene.