Abstract:
The present invention discloses a process for efficient production of 2-amino-5- hydroxypropiophenone corresponding to the AB ring part of camptothecin (CPT) skelton, which is a key intermediate useful for the total synthesis of camptothecin analogs including 7-Ethyl-10-hydroxy camptothecin and novel intermediates thereof.
Abstract:
A process for preparing trinitrololuene (TNT) in which toluene is treated with nitric acid having a concentration of about 90% to about 99%, and preferably about 98% to about 99%, by weight at a temperature of less than about 60°C, and preferably less than 30°C, to produce high purity dinitrotoluene. The resulting dinitrotoluene is then treated with nitric acid having a concentration of about 98% to about 99% by weight and trifluoromethane sulfuric acid to produce high purity TNT.
Abstract:
A process by which 2,5-bis(trifluoromethyl)nitrobenzene can be produced from an industrially easily available material in high yield through a small number of steps under mild reaction conditions using an easily handleable substance with which the reaction operation is easy. 1,4-Bis(trifluoromethyl)benzene is nitrated with nitric acid in a solvent comprising as an essential ingredient an acid selected between sulfuric acid having a sulfuric acid concentration of 91 to 100 wt.% and fuming sulfuric acid having a sulfur trioxide concentration higher than 0 wt.% and not higher than 20 wt.%.
Abstract:
A process for the nitration of an aromatic compound, wherein the aromatic compound is admixed with a nitrating agent in the presence of an ionic liquid is described. The method for the nitration of aromatic compounds in (e.g. neutral) ionic liquids has advantages over conventional nitrations, such as the only by-product being water, the ionic liquid not being consumed and the nitrating agent being relatively inexpensive.
Abstract:
A tubular reactor (1) characterized by having short static mixing elements (1, 2, 3, 4, 5, 6, 7, 8, 9, 10) separated by coalescing zones (20, 21, 22, 23, 24, 25, 26, 27) is used to conduct multiphase liquid/liquid reactions. Small droplets of one of the phases are dispersed into the other phase by the static mixing elements (1, 2, 3, 4, 5, 6, 7, 8, 9, 10). These droplets coalesce and at least partially phase separate as the mixture passes through the subsequent coalescing zone. The tubular reactor is particularly suitable for nitrating organic compounds while forming low levels of improperly nitrated by-products and low levels of nitrophenolics.
Abstract:
A process for producing fomesafen from acifluorfen comprises the steps of (a) converting acifluorfen to its acid chloride, (b) coupling the acid chloride so formed with methanesulphonamide to form crude fomesafen and (c) purifying the crude fomesafen, characterised in that each of the steps is carried out in a single common solvent, which is preferably a chloroalkane. Preferably the steps are telescoped together so that there is no isolation of the product for any step until fomesafen is obtained.
Abstract:
A method useful for the synthesis of a meta-substituted nitrogen derivative, comprising the step of deaminating an ortho- and/or para-substituted nitroaniline of the aniline function. The method is useful for organic synthesis.
Abstract:
Porous microcomposites have been prepared from "NAFION3" ion-exchange polymer and metal oxides such as silica using the sol-gel process. Such microcomposites possess high surface area and exhibit extremely high catalytic activity.
Abstract:
Method for obtaining 2-nitrobenzaldehide derivatives and nitrobenzoïc acid derivatives having the formula (Ia) (III) respectively, wherein R is H, C1-4 alkyl, C1-4 alkoxy or halogen. The method is comprised of selectively oxidizing a mixture of nitrobenzaldehide derivatives (I) with an aqueous solution of an oxidizing agent (II) wherein X is halogen, M is an alkaline or alkaline-earth metal and n is 1 or 2. Through said oxidation, 3-nitrobenzaldehide derivatives essentially are oxidized. 2-nitrobenzaldehide derivatives (Ia) not oxidized may be removed through the use of a water-unmiscible solvent and the nitrobenzoïc acid derivatives (III) may be precipitated in the aqueous phase by pH regulation. In a preferred mode of execution, 2-nitrobenzaldehide is of pharmaceutical interest as coronary dilator and 3-nitrobenzoïc acid is of interest in the industry of dyes and in medicine as synthesis intermediary.
Abstract:
The present invention provides a process for the conversion of a reactant into a reaction product in the presence of a solid acid catalyst comprising one or more fluorine atoms, sulfo radicals and phosphono radicals, each such radical being bonded to the same or different carbon atom, with the proviso that at least one sulfo radical and at least one phosphono radical are bonded to such carbon atoms through the sulfur atom and the phosphorus atom, respectively. These compounds are preferably non-polymeric, i.e. they have a molecular weight of about 5000 or less. The above acid catalysts may be reacted with a tetravalent metal, e.g. Zr, to provide a solid acid catalyst.