Abstract: The invention relates to a method for carrying out reactions with participation of carbocations, whereby the initial most strongly exothermic phase of the reaction is carried out at high temperature (60 to 120° C.) and short residence time (1 to 30 seconds) in a microreactor and the subsequent less exothermic phases are carried out at optionally lower temperatures in two or more residence time units with longer residence times (1 to 30 seconds).

Abstract: The invention relates to an improved method for producing chiral or enantiomer-enriched beta amino acids, -aldehydes, -ketones and gamma-amino alcohols, during which an allyl amine of formula (I), in which: R1 represents an alkyl radical, a cycloalkyl radical, an alkyl radical, a heterocycle radical or a condensed or bridged ring system; R2, R3, R4 and R5, independent of one another, can represent H or an alkyl radical, a cyclo alkyl radical, an aryl radical, a heterocycle radical or a condensed or bridged ring system or radicals R1, R2, R3 and R4, together, form ring systems that can optionally contain one or more heteroatoms, whereby radicals R1, R2, R3, R4 and R5 can be substituted once or a number of times, and; R6 represents H or an N-protective group, is transformed; a) by ozonolysis in a solvent and; b) subsequent decomposition of the peroxide-containing solution by means of an oxidizing agent or reductive reprocessing, into the corresponding amino compound of formula (II), in which R1, R2, R3, R4 and

Abstract: New genes containing a DNA sequence coding for hydroxynitrile lyase, which genes can be prepared via a primer combination based on the DNA sequence of the 5?-region of the mdl genes from the Prunus serotina and from Prunus amygdalus and/or a primer 2 based on the 3?-region of the DNA sequences of one of the hydroxynitrile lyase isoenzymes from Prunus serotina or from Prunus amygdalus, subsequent amplification with a DNA polymerase using a DNA from organisms, containing genes coding for hydroxynitrile lyase, as templates and cloning, and also recombinant proteins which can be prepared in suitable host cells by heterologous expression of the DNA sequence of said HNL genes, and proteins and fusion proteins derived therefrom and use of said proteins for preparing (R)- or (S)-cyanohydrins.

Abstract: Process for generating 1O2 in which a ferrocene of the formula

Abstract: Process for generating 1O2 in which an Sn(II) salt of the formula

Abstract: New genes containing a DNA sequence coding for hydroxynitrile lyase, which genes can be prepared via a primer combination based on the DNA sequence of of the 5′-region of the mdl genes from Prunus serotina and from Prunus amygdalus and/or a primer 2 based on the 3′-region of the DNA sequences of one of the hydroxynitrile lyase isoenzymes from Prunus serotina or from Prunus amygdalus, subsequent amplification with a DNA polymerase using a DNA from organisms, containing genes coding for hydroxynitrile lyase, as templates and cloning, and also recombinant proteins which can be prepared in suitable host cells by heterologous expression of the DNA sequence of said HNL genes, and proteins and fusion proteins derived therefrom and use of said proteins for preparing (R)- or (S)-cyanohydrins.

Abstract: Process for the preparation of optically highly pure (R)— and (S)—&agr;-hydroxycarboxylic acids, in which either isolated, impure (R)— and (S)—&agr;-hydroxycarboxylic acids prepared by acidic hydrolysis of the (R)— and (S)—cyanohydrins obtained by enzyme-catalyzed addition of a cyanide group donor to the corresponding aldehydes or ketones are recrystallized in an aromatic hydrocarbon, optionally in the presence of a cosolvent, and optically highly pure (R)— and (S)—&agr;-hydroxycarboxylic acids having an optical purity of over 98%ee are obtained or the hydrolysis solution obtained by acidic hydrolysis of the (R)— and (S)—cyanohydrins is treated directly with an aromatic hydrocarbon, optionally in combination with a cosolvent, and is then extracted at hydrolysis temperature, whereupon after cooling of the organic phase the corresponding chemically and optically highly pure (R)— and (S)—&agr;-hydroxycarboxylic acids having an optical purity

Abstract: A process for stabilizing enantiomer-enriched cyanohydrins where citric acid and/or boric acid or boric anhydride is added as a stabilizer to the cyanohydrin to be stabilized.

Abstract: Process for the preparation of carboxylic acid succinimidyl esters by reaction of N-hydroxysuccinimide with a carboxylic acid and a halophosphoric acid ester of the formula ##STR1## in which R.sub.1 and R.sub.2 are identical or different and are a C.sub.2 - to C.sub.6 -alkyl radical or a phenyl radical, or R.sub.1 and R.sub.2 together form a C.sub.6 -aryl radical, in the presence of a base in a diluent at a temperature of 0.degree. C. up to 100.degree. C. and isolation of the corresponding carboxylic acid succinimidyl ester.

Abstract: A process for the preparation of carboxylic acid succinimidyl esters by reaction of N-hydroxysuccinimide with a carboxylic acid and a halophosphoric acid ester of the formula ##STR1## is desired, in which R.sub.1 and R.sub.2 are identical or different and are a C.sub.2 - to C.sub.6 -alkyl radical or a phenyl radical, or R.sub.1 and R.sub.2 The process is carried out in the presence of a base in a diluent at a temperature of 0.degree. C. up to 100.degree. C. with isolation of the corresponding carboxylic acid succinimidyl ester.

Abstract: Process for preparing (S)-cyanohydrins by reacting aldehydes or asymmetrical, aliphatic ketones with hydrocyanic acid in the presence of the (S)-oxynitrilase from Hevea brasiliensis at temperatures of up to at most 10.degree. C.

Abstract: Process for enhancement of enantioselectivity in the enzymatic separation of (R)- and (S)-enantiomers of an asymmetric alkynol, a lipase and in the presence of at least one vinyl ester, in which the acid component has at least 4 C atoms, an organic solvent and with the addition of water. Also disclosed is a process for enhancement of enantioselectivity in the enzymatic separation of (R)- and (S)-enantiomers of an alcohol with the aid of the abovementioned vinyl ester under addition of a second vinyl ester having at least 2 C atoms less in the alkyl chain than the vinyl ester used as esterifying agent.

Abstract: Resolution of asymmetric alcohols by reacting them with a vinyl, propenyl or isopropenyl ester of an alkone- or alkene-di- or tricarboxylic acid in the presence of a lipase, and the use thereof.

Abstract: Process to separate racemic mixtures of beta-hydroxy or beta-acyloxy-delta-valerolactones, which in position 2 and/or 5 of the lactone ring are substituted by hydrogen, alkyl groups having 4 to 20 C atoms, which are optionally penetrated by an oxygen atom, or by aralkyl groups, whereby not both positions are substituted by hydrogen, through reaction of the racemic mixture in the presence of a hydrolase with or without esterifying agent in a diluent and separation of the reaction mixture, which contains an enantiomerically pure beta-hydroxy-delta-valerolactone and an enantiomerically pure beta-acyloxy-delta-valerolactone, through conventional methods into the enantiomically pure compounds,a process for the manufacture of enantiomerically pure oxetanones using said separation process and enantiomerically pure beta-acyloxy-delta-valerolactones.

Abstract: Enantioselective process for the preparation of the S enantiomer of an optically active cyanohydrin by reacting an aldehyde or an asymmetric ketone with a cyanide group donor in the presence of an S-hydroxynitrile lyase in a diluent and isolating the cyanohydrin formed from the reaction mixture.