Abstract: Process for the preparation of 3,4-methylenedioxymandelic acid, wherein glyoxylic acid is reacted with 1,2-methylenedioxybenzene in a strongly acid medium.

Abstract: Process for the preparation of cyclopentadecanolide comprising the steps of converting 13-oxa-bicyclo [10.4.0]-hexadecene-[1(12)] to a lactone of the formula ##STR1## wherein X is an oxygen atom, .dbd.NOH or .dbd.N--NH.sub.2,reducing said lactone to give 15-hydroxy-pentadecanecarboxylic acid and cyclising said acid to give cyclopentadecanolide.

Abstract: Aromatic hydroxy aldehydes are prepared by the simultaneous oxidation and decarboxylation of hydroxy aryl glycolic acids by reacting same with oxidizing agents in aqueous-acid medium.

Abstract: The invention concerns a new process for the production of 2-alkoxy-4-propen-1-yl phenols of the formula ##STR1## in which R represents the methyl or ethyl radical wherein 2-alkoxy phenols of the formula ##STR2## in which R is as defined above, are initially condensed with propionaldehyde in the presence of acid catalysts, and the resulting condensation product is subsequently split by heating in the presence of a basic catalyst to form the phenols of formula I.

Abstract: Salicylaldehyde and other hydroxybenzaldehydes are prepared by oxydation of a hydroxybenzyl alcohol in the presence of a platinum metal catalyst and lead, silver, tellurium or tin or compounds thereof as activator.

Abstract: The containers to be tested are brought into an ultrasonic wave field of which the intensity is assessed so that defective containers are destroyed, while mechanically perfect containers remain unaffected. Since the containers destroyed fall out of their holders, sorting takes place simultaneously.

Abstract: Process for the separation or purification of heat-sensitive compounds by carrier-vapor distillation, wherein the superheated solvent vapor which is loaded with the compound to be distilled is cooled by treatment with condensed solvent in counter-current and the amount of condensed solvent is measured in such a manner that a saturated solution of the compound which is almost at boiling point is formed from the superheated, loaded vapor. The process being especially apted for separating or purifying 4-hydroxybenzaldehydes optionally substituted by one or more C.sub.1 -C.sub.4 -alkoxy groups.

Abstract: The invention concerns new 2-alkoxy-4-alkenyl phenols of the formula ##STR1## wherein R.sub.1 is methyl or ethyl andR.sub.2 and R.sub.3 are different from one another and mean hydrogen or methyl;A process for the preparation of said 2-alkoxy-4-alkenyl phenols comprising condensing 2-alkoxy phenols with butyraldehyde or isobutyraldehyde in the presence of an acid catalyst and thermal splitting the condensation product in the presence of a catalyst; and the use of the new 2-alkoxy-4-alkenyl phenols as odorants.

Abstract: Microorganisms can be rendered inactive without impairing their antigenicity or immunogenicity by treating the microorganisms with ethyleneimine. The microorganism is placed in a suspension containing ethyleneimine up to a final concentration of 0.005 to 2% V/V. The temperature of the ethyleneimine-containing suspension is maintained between 0.degree. and 45.degree. C for between a few hours and 2 days. The excess ethyleneimine is destroyed.

Abstract: Microorganisms can be rendered inactive without impairing their antigenicity or immunogenicity by treating the microorganisms with ethyleneimine. The microorganism is placed in a suspension containing ethyleneimine up to a final concentration of 0.005% to 2% V/V. The temperature of the ethyleneimine-containing suspension is maintained between 0.degree. C and 45.degree. C for between a few hours and 2 days. The excess ethyleneimine is destroyed.

Abstract: Glyoxylic acid is selectively extracted from its aqueous mixture with glyoxal by means of aliphatic or cycloaliphatic alcohol containing about 4 to 8 carbon atoms, a ketone containing about 4 to 8 carbon atoms, and an ester of an aliphatic carboxylic acid and aliphatic alcohol each containing up to about 6 carbon atoms, the esters containing a total of about 3 to 8 carbon atoms, allowing the mixture to stratify and separating the solvent layer enriched in glyoxylic acid.

Abstract: The invention relates to a new process for the production of anethole (4-methoxy propen-1-yl benzene), wherein anisole is condensed with propionaldehyde in the presence of an acid catalyst and the resulting condensation product is subsequently split in the presence of an acid at a temperature in the range from 100.degree. to 300.degree. C.

Abstract: A process for the separation of optically active d- and l-isomers of a compound selected from the group consisting of menthol, neomenthol and isomenthol, which comprises esterifying a d,l-isomeric mixture of the compound with an acid selected from the group consisting of benzoic acid optionally carrying at least one substituent on the benzene ring and hexahydrobenzoic acid; forming a supersaturated solution or a supercooled melt of the d,l-ester; inoculating the solution or melt with crystals of the d- or l-form of the ester to effect selective crystllization of one of the two optical isomers; separating the crystals and subjecting them to hydrolysis to yield the corresponding enantiomorph of the starting compound.