Abstract: The present invention relates to a method for producing 1-hydroxymethyl-1,2-diphenyloxiranes from 2,3-diphenylpropenals by means of epoxidation and reduction. The formation of objectionable by-products can be suppressed in that the reduction is started before the 2,3-5 diphenylpropenal is completely converted. The hydroxymethyl diphenyloxiranes represent valuable intermediate products for producing 1-azolylmethyl-1,2-diphenyloxiranes, wherein the latter can be easily produced from said intermediate products by introducing the azolyl group.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to a method for producing 1-hydroxymethyl-1,2-diphenyloxiranes from 2,3-diphenylpropenals by means of epoxidation and reduction. The formation of objectionable by-products can be suppressed in that the reduction is started before the 2,3-5 diphenylpropenal is completely converted. The hydroxymethyl diphenyloxiranes represent valuable intermediate products for producing 1-azolylmethyl-1,2-diphenyloxiranes, wherein the latter can be easily produced from said intermediate products by introducing the azolyl group.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to a process for the preparation of 1,2,4-triazol-1-ylmethyloxiranes of the formula I in which A and B are identical or different and, independently of one another, are C1-C4-alkyl, phenyl-C1-C2-alkyl, C3-C6-cycloalkyl, C3-C6-cycloalkenyl, tetrahydropyranyl, tetrahydrofuranyl, dioxanyl or phenyl, where the phenyl radical can carry one to three substituents chosen from the group: halogen, nitro, C1-C4-alkyl, Cl-C4-alkyloxy, phenoxy, amino, C1-C2-haloalkyl or phenylsulfonyl, which comprises reacting a) an oxirane of the formula II in which A and B have the meanings given above and L is a nucleophilically substitutable leaving group, with 4-amino-1,2,4-triazole of the formula III to give 4-amino-1,2,4-triazolium salts of the formula IV and b) deaminating the 4-amino-1,2,4-triazolium salts IV with alkali metal nitrites and acid or organic nitrites to give 1,2,4-triazol-1-ylmethyloxiranes of the formula I, and to 4-aminotriazolium salts of the formula IV as i

Abstract: The invention relates to a method for producing 2,3-cis-substituted 2-aryl propenals by condensing a 2-aryl acetaldehyde I with a non-enolizable aldehyde compound II in the presence of a base. The inventive method is characterized in that the reaction is carried out in a solvent mixture comprising at least one water-miscible organic solvent and water at a volume ratio Vsolvent:Vwater ranging between 10:1 and 0.5:1.

Abstract: The present invention relates to a process for preparing 2,3-cis-substituted 2-arylpropenals by condensing a 2-arylacetaldehyde I with a nonenolizable aldehyde compound II in the presence of a base, which comprises carrying out the reaction in a solvent mixture which includes at least one water-miscible solvent and water in a Vsolvent:Vwater ratio of from 10:1 to 0.5:1.

Abstract: The present invention relates to a process for the preparation of 1,2,4-triazol-1-ylmethyloxiranes of the formula I in which A and B are identical or different and, independently of one another, are C1-C4-alkyl, phenyl-C1-C2-alkyl, C3-C6-cycloalkyl, C3-C6-cycloalkenyl, tetrahydropyranyl, tetrahydrofuranyl, dioxanyl or phenyl, where the phenyl radical can carry one to three substituents chosen from the group: halogen, nitro, C1-C4-alkyl, Cl-C4-alkyloxy, phenoxy, amino, C1-C2-haloalkyl or phenylsulfonyl, which comprises reacting a) an oxirane of the formula II in which A and B have the meanings given above and L is a nucleophilically substitutable leaving group, with 4-amino-1,2,4-triazole of the formula III to give 4-amino-1,2,4-triazolium salts of the formula IV and b) deaminating the 4-amino-1,2,4-triazolium salts IV with alkali metal nitrites and acid or organic nitrites to give 1,2,4-triazol-1-ylmethyloxiranes of the formula I, and to 4-aminotriazolium salts of the formula IV as intermediates.

Abstract: The invention relates to a method for producing a longlife, resistant spark plug for internal combustion engines. The electrode (16), according to the invention, of the spark plug is assembled from a plurality of initial parts: an initial part for a corrosion-resistant shell (31'), an initial part for a core (33') of high thermal conductivity, and an initial part for an erosion-resistant region (32'). These initial parts are jointly impact-extruded to form an electrode blank which is formed into the center electrode (16) by machining its head (51) and its region on the combustion-chamber side. Electrodes which are especially highly stressed are given a fourth initial part, which is also to be impact-extruded, consists of highly erosion-resistant material and is still arranged on the combustion-chamber side in front of the erosion-resistant region (32'). The electrode (16) can be used as a center electrode (16), but can also be used, if necessary, as an earth electrode after an embossing and bending process.

Abstract: Bis-[2,5-dithio-1,3,4-thiadiazole] corresponding to the following formula: ##STR1## is obtained by reacting 2,5-dimercapto-1,3,4-thiadiazole and hydrogen peroxide in the absence of other reactants.

Abstract: 2-(Hydrocarbyldithio)-5-mercapto-1,3,4-thiadiazoles are obtained by reacting bis-(2,5-dithio-1,3,4-thiadiazole with a tert.-hydrocarbyl mercaptan of which the hydrocarbyl moiety contains from 4 to 60 carbon atoms.

Abstract: To manufacture a vibration-resistant, shock-resistant electrical connection on a ceramic substrate (11) having an electrically conductive layer (12) applied to a surface (13, 19) thereof, a groove or channel-like depression (16, 20) is formed in the surface, preferably also including a through-bore (18), into which a conductor (17) is placed. The space between the conductor and the groove, the through-bore, if provided, and an extending groove at the other surface (19) of the substrate is filled with a sinterable mass (21), preferably a cermet, containing a metal which is compatible with the metal of the conductor wire (17), both for example containing platinum. As a starting material, the plate with the grooves therein is extrusion-pressed, pre-sintered at a low temperature to give it form stability, then the electrode (12) is applied, then the electrical conductor (17) and the cermet is applied and then the entire sub-assembly is fired to sintering temperature, e.g. about 1500.degree. C.

Abstract: To improve operation and output voltage, particularly at 400.degree. C. and less, an oxygen sensor, especially adapted to determine oxygen content of automotive exhaust gases, is constructed by utilizing two electrodes applied on a body of stabilized zirconium dioxide, for example a closed tube, by making an electrode exposed to the exhaust gases in form of a mixture of finely dispersed ceramic material and a platinum-rhodium alloy, the ceramic material being present at about 40% (by volume) and 60% (by volume) platinum-rhodium alloy of 50-94% platinum and 50-6% rhodium (by weight). The second electrode, exposed to a reference gas comprises an alloy of palladium and another noble metal in a ratio of about 19-90% (by weight) Pd and 81-10% (by weight) noble metal. This electrode may also contain up to 40% (by volume) finely dispersed ceramic material. The electrode exposed to the exhaust gases is covered with a porous coating.