Abstract: The present invention relates to a process for preparing 4,6-dichloropyrimidine by reaction of 4-chloro-6-hydroxypyrimidine with an acid chloride.

Abstract: The present invention relates to a process for preparing 4-chloro-6-hydroxypyrimidine from 4-chloro-6-methoxypyrimidine.

Abstract: The invention relates to a method for the preparation of 4,6-dichloropyrimidine by reacting 4-chloro-6-methoxypyrimidine with at least one sulphur-containing chlorinating agent selected from the group consisting of SCl2, SOCl2, and SO2Cl2 in the presence of at least one phosphorus compound having the formula R3P═Yn  (1), in which R represents C1-C10-alkyl or C6-C10-aryl, each of which may optionally be substituted by up to five identical or different substituents selected from the group consisting of fluorine, chlorine, bromine, C1-C4-alkyl, and C1-C4-alkoxy, Y represents oxygen or sulphur, and n represents zero or 1.

Abstract: The present invention relates to a process for preparing 4,6-dichloro-pyrimidine by reaction of 4-chloro-6-methoxypyrimidine with an acid chloride in the presence of a hydrogen halide.

Abstract: The invention relates to a method for the preparation of 4,6-dichloropyrimidine by reacting 4-chloro-6-methoxypyrimidine with phosgene as chlorinating agent in the presence of a nitrogen-containing auxiliary.

Abstract: 4,6-Dichloropyrimidines are obtained by the reaction of 4,6-dihydroxypyrimidines with excess phosphoryl chloride in a particularly advantageous manner when no base is added, during and/or after the reaction 0.75 to 1.5 mol of phosphorus trichloride and 0.7 to 1.3 mol of chlorine are added per equivalent of exchanged hydroxyl groups so that an excess of phosphorus trichloride with respect to chlorine is always present, and finally phosphorus trichloride and phosphoryl chloride are separated off. This process can be carried out in a particularly simple manner and also continuously.

Abstract: 2-Chloropyridine derivatives of the formula (I) ##STR1## in which R represents hydrogen, C.sub.1 -C.sub.4 -alkyl or halogen andn represents 0 to 4,are obtained in good yields and high purity when a 2-aminopyridine derivative of the formula (II) ##STR2## in which R and n have the above definitions,is reacted with nitrosyl chloride in a hydrogen chloride-saturated aqueous solution at temperatures between -10.degree. C. and +50.degree. C. with simultaneous introduction of hydrogen chloride.

Abstract: The present invention relates to agents for increasing the retention of fibres, fillers and pigments and for accelerating drainage in papermaking, and as flocculating agents in the working up of effluents from papermaking by filtration, sedimentation and flotation. They are characterized in that they contain, as active components, one or more nitrogen-containing condensation products which can be obtained by reacting (A) aliphatic polyol-ether-amines which are free from halogen groups, contain cohesive polyether segments and carry no amino groups within these segments, with (B) compounds which are polyfunctional towards amino groups, optionally in the presence of (C) polyaminopolyamides and/or (D) polyalkylenepolyamines, component (B) being employed in an amount such that water-soluble polycondensates which have a viscosity of 100 to 1,000 mPa.s at 25.degree. C. in 25% strength aqueous solution are formed.

Abstract: Non-crosslinking, water-soluble polyamines which can be obtained by reacting(A) basic polyureas which have been prepared by condensation of ureas with polyamines containing at least three amino groups, of which at least one is a tertiary amino group, or with mixtures of these polyamines with aliphatic, araliphatic, cycloaliphatic or heterocyclic polyamines containing two primary or two secondary amino groups or one primary or one secondary amino group, and optionally with .omega.-aminocarboxylic acids containing at least three carbon atoms, or lactams thereof,(B) polyalkylenepolyamines of the general formula ##STR1## in which R denotes H or CH.sub.

Abstract: Non-crosslinking, water-soluble polyamines which can be obtained by reacting(A) basic polyureas which have been prepared by condensation of ureas with polyamines containing at least three amino groups, of which at least one is a tertiary amino group, or with mixtures of these polyamines with aliphatic, araliphatic, cycloaliphatic or heterocyclic polyamines containing two primary or two secondary amino groups or one primary or one secondary amino group, and optionally with .omega.-aminocarboxylic acids containing at least three carbon atoms, or lactams thereof,(B) polyalkylenepolyamines of the general formula ##STR1## in which R denotes H or CH.sub.

Abstract: In the production of thiocarbohydrazide by reacting hydrazine hydrate with carbon disulphide in the presence of water to form in a first stage hydrazinium dithiocarbazinate, subsequently thermally decomposing the hydrazinium dithiocarbazinate in a second stage to form thiocarbohydrazide, and recovering the thiocarbohydrazide from the reaction medium, the improvement which comprises effecting the entire reaction in the mother liquor of a preceding batch, carrying out the first reaction stage at a temperature between about 25.degree. C. and 45.degree. C., with injection of carbon disulphide below the surface of the reaction mixture; carrying out the second stage at about 62.degree. to 65.degree. C. without prior isolation of the intermediate product; filtering off the thiocarbohydrazide formed after cooling, separating the amount of mother liquor in excess of that required for the next batch, and feeding the balance of the mother liquor to the next batch.

Abstract: Water-soluble amines which are not self-crosslinking and are obtainable by reacting(A) one or more water-soluble or water-dispersable amines containing amide groups, prepared by condensation of (a) 1 mol of dicarboxylic acid or functional derivatives thereof, (b) 0 to 30 mols of aminocarboxylic acids containing at least three C atoms, or lactams thereof, and (c) 1.4 to 30 mols of polyalkylenepolyamines of the general formula ##STR1## in which R denotes H or CH.sub.3,y is in each case the same or different and denotes the number 0 or 1 andx denotes a number from 4 to 15,and(B) compounds which are polyfunctional towards amino groups, are suitable as agents for increasing the retention of fibres, fillers and pigments, for accelerating drainage during the production of paper and for working up effluents from paper machines.

Abstract: Water-soluble polyamines which are obtainable by reacting(A) one or more water-soluble or water-dispersible basic polyamides which have been prepared by condensation of aliphatic polyamines containing at least two primary amino groups and at least one secondary or tertiary amino group, or of mixtures of these polyamines and of aliphatic, cycloaliphatic, araliphatic or heterocyclic polyamines containing two primary or two secondary amino groups or one primary and one secondary amino group, with saturated aliphatic dicarboxylic acids containing 4-10 carbon atoms, or with functional derivatives thereof and optionally with .omega.-aminocarboxylic acids containing at least 3 carbon atoms, or lactams thereof,(B) one or more polyalkylenepolyamines of the general formula ##STR1## in which R denotes H or CH.sub.

Abstract: 4-Alkylthiosemicarbazides of the formulaAlkyl--NH--CS--NH--NH.sub.2are produced by heating at about 40 to 90.degree. C the novel hydrazinium salts of N-alkyldithiocarbamic acids of the formulaAlkyl--NH--CS--S.sup.- + NH.sub.3 --NH.sub.2in a solvent while removing by-product H.sub.2 S as by use of vacuum or passage of an inert gas through the reaction mixture, advantageously in the presence of a catalytic amount of sulfur to speed up the reaction. Hydrazine hydrate may also be present. The hydrazinium salt starting material can be prepared by reacting the corresponding alkylamine, ammonia, carbon disulfide and hydrazine, and the reaction solution directly employed in the heating step of the present invention without isolation of the intermediate.