Abstract:
Nitroimdazolyivinylthiadiazoles (I, R1 = C1-4 alkyl; R2 = H, CH3; R3 = H, C1-24 alkyl, substitutable ph, heteroallyl) useful agents for treating bacteria, fungi and protozoa, were prepd. by the reaction of 2-substituted-1,3,4-thiadiazole(II) and 5-nitroimidazole-2-carboxaldehyde(III) or its acetal at elevated temp. Thus, 2,5-dimethy 1-1,3,4-thiadiazole and 1-methyl-5-nitroimidazole-2-carboxy aldehyde were refluxed in glacial acetic acid and acetic anhydride in the presence of ZnCl2 for 10 hr and recrystallized with DMF to give -methyl-5-[2-(1-methyl-5-nitroimidazol-2-yl)-vinyl -1,3,4-thiadiazloe(m.p. 248≦̸C).
Abstract:
AN IMPROVED PROCESS FOR THE PRODUCTION OF LACTONES HAVING SIX TO THIRTEEN RING MEMBERS AND ISOBUTYRIC ACID BY REACTION OF A CYCLIC KETONE HAVING FROM FIVE TO TWELVE RING MEMBERS AND ISOBUTYRIC ACID BY REACTION OF A CYCLIC KETONE HAVING FROM FIVE TO TWELVE RING MEMBERS AND ISOBUTYRALDEHYDE WITH MOLECULAR OXYGEN OR A GAS CONTAINING THE SAME, THE IMPROVEMENT CONSISTING IN CARRYING OUT THE REACTION WITHOUT USING A CATALYST. LACTONES ARE USED IN THE PRODUCTION OF POLYESTOR.
Abstract:
PROBLEM TO BE SOLVED: To avoid production of ether which is a by-product from an alkanol in a method for continuously producing an alkyl ester of a (meth)acrylic acid by reacting (meth)acrylic acid with a 1-8C monohydric alkanol in a reaction zone in the presence of an acid esterification catalyst, discharging a product mixture containing the resultant alkyl (meth)acrylate, the catalyst and a by- product having higher boiling point than the alkyl (meth)acrylate and subjecting the alkyl (meth)acrylate to separation by distillation in a separation zone from the mixture. SOLUTION: A product mixture from a reaction zone is fed to a rectifier I and the product mixture discharged in the apparatus is separated into one or more products I containing an alkyl ester of (meth)acrylic acid and product II containing a catalyst by rectification and the product I is fed to other rectifier II and an alkyl ester of (meth)acrylic acid is separated by rectification in the apparatus.
Abstract:
PROBLEM TO BE SOLVED: To obtain the subject compound of high purity in high yield with suppression of the formation of by-products by treating a vinyloxy-ester of a carboxylic acid in the presence of an alcohol. SOLUTION: An α,β-unsaturated carboxylic ester of formula I (R is H, a 1-4C alkyl; R is H, methyl) is subjected to the transesterification, with a vinyloxy group-bearing alcohol of the formula: CH2 =CH-O-A-OH (A is a 2-12C alkylene) in the presence of a base catalyst to prepare a vinyloxy carboxylic ester of formula II. In addition, the compound of formula II is allowed to react with an alcohol, preferably 1,2-diol or 1,3-diol to prepare an α,β-unsaturated carboxylic ω-hydroxyester thereby giving a compound of formula III not accompanied by formation of by-products such as cyclic ethers or diesters through an environmentally acceptable and usually applicable process.
Abstract:
Manufacture of carboxamides by the addition of water to nitriles in the presence of a copper-containing and magnesium silicatecontaining catalyst which has been treated with a reducing gas. The carboxamides obtained by the process of the invention are valuable starting materials for the manufacture of solvents, flocculating agents, crosslinking agents, pesticides, plant protectants, textile auxiliaries such as levelling agents, waterproofing agents, foam stabilizers and detergents.
Abstract:
PROCESS FOR PRODUCING LACTIC ACID BY THE HYDROLYSIS OF LACTIC ACID NITRATE IN WHICH THE LACTICE ACID NITRATE IS REACTED WITH MORE THAN TWICE ITS WEIGHT OF WATER. IT HAS BEEN FOUND THAT HIGH YEILDS OF LACTICE ACID CAN BE OBTAINED EITHER FROM PURE LATICE ACID NITRATE OR FROM THE REACTION PRODUCT CONTAINING IMPURITIES AS WELL AS LACTIC ACID NITRATE.
Abstract:
The invention relates to a method for continually producing 1,3-dioxolan-2-ones such as ethylene carbonate or propylene carbonate by reacting a corresponding oxirane with carbon dioxide in liquid phase in the presence of a catalyst. The reaction is carried out in a two-part reactor. In the first part of the reactor, the reaction is carried out with back-mixing until a conversion rate of oxirane II of at least 80 % has been reached. In the second part, the reaction is completed under conditions without back-mixing, the carbon dioxide being guided to the oxirane II in a counterflow throughout the reactor.
Abstract:
The invention relates to a method for continually producing 1,3-dioxolan-2- ones such as ethylene carbonate or propylene carbonate by reacting a corresponding oxirane with carbon dioxide in liquid phase in t he presence of a catalyst. The reaction is carried out in a two-part reactor. In the first part of the reactor, the reaction is carried out with back-mixing until a conversion rate of oxirane II of at least 80 % has been reached. In the second part, the reaction is completed under conditions without back-mixing, the carbon dioxide being guided to the oxirane II in a counterflow throughout the reactor.
Abstract:
Procedimiento para separar iones metálico alcalinos de alcoxilados que contienen iones metálico alcalinos, que comprende: a) dilución del alcoxilado que contiene metal alcalino con un solvente inerte, b) tratamiento de la solución de alcoxilado que contiene metal alcalino con cambiador de cationes, para obtener una solución que contenga menos de 5 ppm de iones metálico alcalino, c) eliminación del solvente de la solución esencialmente libre de metal alcalino, para obtener un alcoxilado que contenga menos de 5 ppm de iones metálico alcalinos y menos de 1 000 ppm de solvente, siendo el procedimiento uno que comprende una regeneración del cambiador de cationes que consta de las siguientes etapas: d1) eliminación de la solución de alcoxilado a partir del cambiador de cationes y elución del cambiador de cationes con un solvente inerte, d2) elución, si es necesario, del cambiador de cationes con agua desmineralizada, d3) regeneración de la resina cambiadora de cationes con un ácido, d4) relavadode la resina cambiadora de cationes con agua desmineralizada, d5) elución del agua que se encuentra en la resina cambiadora de iones con un solvente inerte, y d6) si es necesario, cargar el cambiador de cationes con el solvente inerte deseado para el tratamiento con el cambiador de cationes, eliminando en la etapa d1) la solución de alcoxilado del cambiador de cationes, presionándolo con un gas inerte.