Abstract: The present invention relates to a process for the selective preparation of 3-methylpyridine, characterized in that acrolein and one or more ammonium salt(s) dissolved in water are reacted continuously under high pressures and at temperatures of 200-400° C.

Abstract: The present invention relates to a process for the selective preparation of acetaldehyde, characterized in that acrolein and one or more ammonium salts dissolved in water are reacted continuously under high pressures and at temperatures of 300-400° C.

Abstract: A method for the production of 6,6,6-trihalo-3,5-dioxohexanic acid esters of formula (I): in addition to the enols thereof and <I>E</I> and <I>Z</I> isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.

Abstract: The invention relates to a method for the production of an thioacetic acid and salts thereof of formulae (I) and (II), wherein Mn+represents ammonium or an alkali metal cation, alkaline earth metal cation, aluminum cation or titanium cation, by reacting ketene with hydrogen sulphide in the presence of a nitrogenous base or reacting ketene with an aqueous alkali metal hydrogen sulphide solution. The thioacetic acid thus formed can be, optionally, subsequently transformed into the corresponding salt by reacting it with ammonia or an alkali metal base, alkaline earth metal base, aluminum base or titanium base. The transformation of thioacetic acid and the formation of salt is carried out as a one-pot method.

Abstract: A method for the production of 6,6,6-trihalo-3,5-dioxohexanic acid esters of formula (I): in addition to the enols thereof and <I>E</I> and <I>Z</I> isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.

Abstract: The invention relates to ?-alanine amides of general formula (I), wherein: R1 represents hydrogen or C1-6 alkyl that is optionally substituted by hydroxy, amino, carboxy, carbamoyl, methylmercapto, guanidino, optionally substituted aryl or heteroaryl, and; R2 represents hydrogen or R1 and R2, together, form a group of formula —(CH2)n—, wherein n is 3 or 4. Said ?-alanine amides are produced without using an amino protective group by reacting the corresponding amine with a cyanoacetic ester in order to form an acetamide and by effecting a subsequent catalytic hydrogenation. The method is suited, in particular, for producing carcinine (?-alanyl-histamine, R?1 =imidazol-4-ylmethyl, R2=H), a naturally occurring pseudo dipeptide, which is used as an active ingredient having an antioxidative effect in medicaments and cosmetics.

Abstract: A method for the production of 6,6,6-trihalo-3,5-dioxohexanoic acid esters of formula (I): in addition to the enols thereof and <I>E</I> and <I>Z</I> isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.

Abstract: A method for the production of 6,6,6-trihalo-3,5-dioxhexanoic acid esters of formula (I): in addition to the enols thereof and <I>E</I> and <I>Z</I> isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.

Abstract: A method for the production of 6,6,6-trihalo-3,5-dioxohexanic acid esters of formula (I): in addition to the enols thereof and <I>E</I> and <I>Z</I> isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.

Abstract: A method for the production of 6,6,6-trihalo-3,5-dioxohexanic acid esters of formula (I): in addition to the enols thereof and <I>E</I> and <I>Z</I> isomers, wherein X independently represents fluorine, chlorine or bromine and R1 represents alkyl, cycloalkyl, aryl or aralkyl. A method for the production of enol ethers of formula (Ib): and the enols thereof (E and Z isomers) wherein X and R1 have the above-mentioned meanings.

Abstract: Described are prepolymer compositions on the basis of novolak cyanates of the general formula wherein n is a number from 0 to 20 and the radicals R are identical or different and represent hydrogen or methyl. The compositions contain: 30 to 90 parts by weight of a prepolymer from novolak cyanates (I) wherein R=hydrogen (Ia) and 10 to 70 parts by weight of novolak cyanates (I) wherein R=methyl (Ib), and optionally highly disperse silicon dioxides and/or particulate or fibrous fillers. The inventive compositions are solid at normal temperature and can be ground to flowable powders. They have excellent stability when stored and are easy to process and especially suitable for use as the resin component in base materials for printed circuits on resin-bound abrasive products.

Abstract: Compounds of the general Formula: in which R1 and R2 are at each occurrence independently hydroxyl, C1-6-alkyl, C1-6-alkoxy, halogen, phenyl or phenoxy; R2 is hydroxyl, C1-6-alkyl, C1-6-alkoxy, halogen, phenyl or phenoxy; R3 is C1-6-alkyl; m is an integer from 0 to 4; and n is an integer from 0 to 5.

Abstract: The method for producing N-alkoxy-N-alkylamides of general formula (I): wherein R1 represents C1-10-alkyl, cyclo-C5-7-alkyl, cyclo-C5-7-alkenyl, C2-10-alkenyl, aryl, aryl-C1-3-alkyl, heteroaryl, heteroaryl-C1-3-alkyl or heterocyclyl; and R2 represents C1-6 alkyl. In the process, an ester of general formula (II): R1COOR3, wherein R1 has the above-mentioned meaning, and R3 represents C1-6-alkyl, 4-nitrophenyl, 2,4-dinitrophenyl, succinimido or benzotriazole-1-yl, is reacted with hydroxylamine, a hydroxylamine derivative or with a hydroxylammonium salt, and the reaction product is alkylated in the presence of a phase transfer catalyst.

Abstract: The invention relates to &bgr;-alanine amides of general formula (I), wherein: R1 represents hydrogen or C1-6 alkyl that is optionally substituted by hydroxy, amino, carboxy, carbamoyl, methylmercapto, guanidino, optionally substituted aryl or heteroaryl, and; R2 represents hydrogen or R1 and R2, together, form a group of formula —(CH2)n—, wherein n is 3 or 4. Said &bgr;-alanine amides are produced without using an amino protective group by reacting the corresponding amine with a cyanoacetic ester in order to form an acetamide and by effecting a subsequent catalytic hydrogenation. The method is suited, in particular, for producing Carcinine (&bgr;-alanyl-histamine, R?1 =imidazol-4-ylmethyl, R2=H), a naturally occurring pseudo dipeptide, which is used as an active ingredient having an antioxidative effect in medicaments and cosmetics.

Abstract: Compounds of the general Formula: 1

Abstract: Described are prepolymer compositions on the basis of novolak cyanates of the general formula 1

Abstract: A method for producing compounds of general formula (I): wherein R1 and R2, each time they occur and independently of each other, mean hydroxyl, C1-6-alkyl, C1-6-alkoxy, halogen, phenyl or phenoxy; R3 means hydrogen or C1-6-alkyl; m is a whole number from 0 to 4; and n is a whole number from 0 to 5. According to the method, diketene is reacted with an N-phenyl-p-phenylenediamine of general formula (II): wherein R1, R2, R3, m and n have the meanings given above, in the presence of 3 to 40 percent acetic acid and at temperatures of 20 to 100° C. The compounds (I) with R3 is C1-6-alkyl and the enamines can be obtained from these by reaction with ammonia, and their hydration products.

Abstract: A method for producing cyanoacetic acid esters of general formula (I): wherein R represents on optionally substituted linear or branched C1-8 alkyl group or an aryl C1-4 alkyl group. According to the method, an alkoxypropionitrile of the general formula (II): wherein R is defined above, is oxidized to form the desired product in the presence of a catalyst, based on lead or on one of the transition metals, using oxygen or an oxygen-forming reagent.

Abstract: A method for producing &agr;-dicarbonyl compounds of formula (I): wherein R1 and R2, independently of each other, mean C1-6-alkyl. In the method, an &agr;,&bgr;-unsaturated ketone of formula (II): wherein R1 and R2 have the meaning above and R3 and R4, independently of each other, mean hydrogen, C1-6-alkyl or di-C1-6-alkylamino, is reacted with ozone in the absence of a catalyst and the resultant ozonide is treated reductively.

Abstract: The invention relates to a novel method for producing robenidine and salts thereof of the general formula wherein X denotes a halogen atom. The method uses hydrazine hydrate and a cyano compound YCN as the starting materials, which are first reacted to projuce a diaminoguanidine of the general formula wherein Y denotes a halogen atom or tosyl. This diaminoguanidine is then converted directly, without isolation, by reacting with a p-halobenzaldehyde of the general formula IV to produce the robenidine and salts thereof of general formula I.