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| Number | Title | Issue Date |
| 7078571 | Preparation of 1,3-di-halo-substituted benzene derivatives A process for preparing 1,3-di-halo-substituted benzene derivatives (II) from 2,6-di-halo-substituted benzaldehydes (I) (where X1, X2 are each independently F, Cl, Br, and R1, R2, R3 are each independently H, ha... | 07/18/2006 |
| 6943257 | Process for preparation of aromatic halides from aromatic amines The present invention provides a process for preparing an aromatic bromide or aromatic iodide from an aromatic amine derivative using nitrite anion and halodimethylsulfonium halide generated in situ from hydrobromic acid/DMSO or hydriodic acid/DMSO. The process for ... | 09/13/2005 |
| 6353142 | Process for the adiabatic preparation of 3,4-dichloronitrobenzene 1,2-Dichlorobenzene can be reacted very selectively under adiabatic reaction conditions to give 3,4-dichloronitrobenzene by intensively mixing 1,2-dichlorobenzene with nitric acid, sulphuric acid and water, simultaneously or successively, in their total a... | 03/05/2002 |
| 6329529 | Nitrogen-based halogenating agents and process for preparing halogen-containing compounds Disclosed are a fluorinating agent represented by the general formula (1): ##STR1## wherein R1 to R4 are a substituted or unsubstituted, saturated or unsaturated alkyl group or a substituted or unsubstituted aryl group, and can be th... | 12/11/2001 |
| 6114589 | Process for the preparation of fluorinated aromatic compounds The invention relates to a process for the preparation of fluorinated compounds Azx ArFw Cl.sub.(y-w) Rz (1) in which Az is a radical --F, --Cl, --Br, --NO2, --CN, --CF3, --CCl3 | 09/05/2000 |
| 5837761 | Pigmented plastics compositions A plastics composition comprising a high molecular weight material and an effective coloring amount of an azo pigment of formula ##STR1## where M is Mg, Ca, Sr, Ba or Mn or a mixture of two or more thereof, R1 and R2 are chlorin... | 11/17/1998 |
| 5773651 | Process for the preparation of fluorine-containing chemical compounds Process for the preparation of fluorine-containing compounds by reduction in a container provided with a stirrer, the stirrer being constructed entirely or partly of a carbon material.... | 06/30/1998 |
| 5756834 | Process for preparing fluorinated aromatics It is known to prepare fluorinated aromatic compounds of the formula I ##STR1## in which X, Y and Z can have the meaning specified in the description, by reacting aromatic compounds of the formula II ##STR2## in which X, Y and Z have the meaning... | 05/26/1998 |
| 5728901 | Nitration process which employs water tolerant Lewis acid catalysts A process for preparing a nitrated arene which comprises reacting an arene and nitric acid in the presence of a water tolerant Lewis acid catalyst under process conditions sufficient to form the nitrated arene and recovering the nitrated arene. Suitable L... | 03/17/1998 |
| 5714647 | Process for the adiabatic preparation of mononitrohalogenobenzenes Mononitrohalogenobenzenes can be prepared by mixing halogenobenzene, nitric acid, sulphuric acid and water intensively with one another, simultaneously or in succession in their total quantity, and by redispersing them at least twice in the case of contin... | 02/03/1998 |
| 5545768 | Process for the preparation of chlorofluronitrobenzenes and difluoronitrobenzenes A process for the preparation of chlorofluoronitrobenzenes and difluoronitrobenzenes, which comprises heating dichloronitrobenzene to not more than 200° C. in excess with an alkali metal fluoride having a total water content of about 0.2 to about 2.5% by... | 08/13/1996 |
| 5502260 | Process for preparing multiply fluorinated nitrobenzenes Multiply, preferably doubly or triply, fluorinated nitrobenzenes are prepared in an advantageous way from the corresponding chloronitrobenzenes and an alkali metal fluoride in a chlorine-fluorine exchange reaction by catalyzing the reaction with a quatern... | 03/26/1996 |
| 5476976 | Process for preparing fluoronitrobenzenes Fluoronitrobenzenes are prepared in an advantageous way from the corresponding chloronitrobenzenes and an alkali metal fluoride by means of a chlorine-fluorine exchange reaction with replacement of a chlorine atom by a fluorine atom, by catalyzing the rea... | 12/19/1995 |
| 5475163 | Process for the preparation of 2,3-dichloro-nitrobenzene 2,3-dichloro-nitrobenzene can be prepared by nitration of 1,2-dichlorobenzene using an anhydrous mixture of phosphoric acid, sulphuric acid and nitric acid. The conditions according to the invention displace the ratio of 2,3,-dichloro-nitrobenzene and ... | 12/12/1995 |
| 5463148 | Process for the preparation of chlorofluoronitrobenzenes A process for the preparation of chlorofluoronitrobenzenes in high yields, by reacting dichloronitrobenzenes with alkali metal fluorides having a water content of up to about 2.5% by weight in the presence of a quaternary ammonium and/or phosphonium salt,... | 10/31/1995 |
| 5349098 | Process for producing chlorofluorobenzenes A process for producing chlorofluorobenzenes, which comprises reacting fluorine-containing nitrobenzenes of the following formula (1) with chlorine gas to obtain chlorofluorobenzenes of the following formula (2): ##STR1## wherein n and m are integers... | 09/20/1994 |
| 5315043 | Aromatic nucleophilic fluorination A process for halogen exchange fluorination or fluoro-denitration of aromatic compounds having at least one replaceable non-fluorine halogen or nitro substituent with an anhydrous substantially molten alkali metal acid fluoride composition wherein the alk... | 05/24/1994 |
| 5294742 | Process for preparing 3,5-difluoroaniline Process for preparing 3,5-difluoroaniline, wherein (1) 2,4,5-trichloronitrobenzene is reacted with an alkali metal fluoride in the presence or absence of a polar aprotic solvent at temperatures of about 100° C. to about 250° C., and, after filtering off ... | 03/15/1994 |
| 5247124 | Process for the preparation of substituted styrenes A process for preparing a substituted styrene by reacting a bisarylalkyl ether in the presence of an acid catalyst is disclosed. The process is preferably used for the preparation of 4-acetoxystyrene from 4,4'-(oxydiethylidene)bisphenol diacetate and 4-me... | 09/21/1993 |
| 5208394 | Process for producing chlorofluorobenzenes A process for producing chlorofluorobenzenes, which comprises reacting fluorine-containing nitrobenzenes of the following formula (1) with chlorine gas to obtain chlorofluorobenzenes of the following formula (2): ##STR1## wherein n and m are integers... | 05/04/1993 |
| 5194672 | Process for the preparation of substituted styrenes A process for preparing a substituted styrene by reacting a bisarylalkyl ether in the presence of an acid catalyst is disclosed. The process is preferably used for the preparation of 4-acetoxystyrene from 4,4'-(oxydiethylidene)bisphenol diacetate and 4-me... | 03/16/1993 |
| 5162583 | Benzylether derivatives Disclosed herein are the derivative of benzyl ether represented by the formula (I) ##STR1## which is useful as an intermediate compound of the derivatives of 1,5-diphenyl-1H-1,2,4- triazole-3-carboxamide represented by the formula (II), ##S... | 11/10/1992 |
| 5104491 | Method for purifying pentachloronitrobenzene by solid base treatment Crude pentachloronitrobenzene containing hexachlorobenzene and small amounts of acids is treated in the molten state or in a mixture solution of nitrobenzene or chloronitrobenzenes with an inorganic basic substance and then subjected to a distillation und... | 04/14/1992 |
| 5041674 | Process and intermediates for the preparation of 2,6-difluoroaniline 1-Chloro-3,5-difluorobenzene is chlorinated to give 4,6-difluoro-1,2,3-trichlorobenzene which in turn is nitrated and reduced to the corresponding novel aniline, 2,6-difluoro-3,4,5-trichloroaniline. Further reduction of this aniline provides 2,6-difluoroa... | 08/20/1991 |
| 4978769 | Process for introducing fluorine atoms into aromatic rings by nucleophilic exchange Aromatic, ring-fluorinated compounds are particularly advantageously prepared by nucleophilic exchange in the course of reaction wih potassium fluoride in the presence of phase transfer catalysts and, if desired, solvents by carrying out the reaction in t... | 12/18/1990 |
| 4973772 | Catalytic method for producing fluoroarmatic compounds using substituted pyridinium salts A process is disclosed for preparing fluoroaromatic compounds (such as fluoronitrobenzene compounds) by reaction of corresponding chloroacromatic compounds (such as chloronitrobenzene compounds) with alkali metal fluoride salts in the presence of alkyldio... | 11/27/1990 |
| 4973771 | Phase transfer catalysts N-secondary-alkyldiorganoaminopyridinium salts are disclosed which are useful as phase transfer catalysts for facilitating preparation of fluoroaromatic compounds (such as fluoronitrobenzene compounds) from the corresponding chloroaromatic compounds (such... | 11/27/1990 |
| 4927980 | Catalytic method for producing fluoroaromatic compounds using branched alkyl pyridinium salts A process is disclosed for preparing fluoroaromatic compounds (such as fluoronitrobenzene compounds) by reaction of corresponding chloroaromatic compounds (such as chloronitrobenzene compounds) with alkali metal fluoride salts in the presence of alkyldior... | 05/22/1990 |
| 4898996 | Process for producing 3-chloro-4-fluoronitrobenzene A process for producing 3-chloro-4-fluoronitrobenzene which is characterized by chlorinating 4-fluoronitrobenzene in the presence of: (1) iodine or an iodide in combination with iron or an iron compound or (2) iodine or an iodide in combination with antimony or an ... | 02/06/1990 |
| 4876404 | Preparation of dichlorotrifluoromethyltoluenes including novel isomers Dichlorotrifluoromethyltoluenes useful in producing some medicines and agricultural chemicals are formed with good yields by reacting dichlorotrichloromethyltoluenes with hydrogen fluoride usually at 0°-100° C. under pressure of 3-20 kg/cm2. ... | 10/24/1989 |
| 4868347 | Process for obtaining substituted fluorobenzenes Substituted fluorobenzenes which are produced in aprotic, polar solvents or in mixtures which contain such solvents can be obtained by extracting the substituted fluorobenzenes from the solvents or solvent mixtures with aliphatic extracting agents and the... | 09/19/1989 |
| 4849552 | Preparation of fluoroaromatic compounds in dispersion of potassium fluoride An improved process is disclosed for preparing fluoroaromatic compounds (such as fluoronitrobenzene compounds) wherein chloroaromatic compounds (such as chloronitrobenzene compounds) are reacted with potassium fluoride in a solvent dispersion thereof prep... | 07/18/1989 |
| 4842696 | Purification of pentachloronitrobenzene by distillation Pentachloronitrobenzene (PCNB) which initially contains in excess of 0.5% hexachlorobenzene (HCB) is purified by distilling the impure PCNB at a temperature between 100°-250° C. and a pressure below or at atmospheric pressure to obtain a PCNB product ha... | 06/27/1989 |
| 4826982 | Quinolonecarboxylic acid derivatives Quinolonecarboxylic acid derivatives of the following formula, ##STR1## wherein R1, R2, R3 and R4 are each independently hydrogen atom or lower alkyl group; the hydrates or the pharmaceutically acceptable a... | 05/02/1989 |
| 4780559 | Process for preparing organic fluorides A method for the preparation of organic fluorides which comprises reacting a quaternary phosphonium fluoride or bifluoride with an organic substrate having at least one atom or group capable of being replaced by a fluorine atom.... | 10/25/1988 |
| 4704483 | 3,4-difluoro-5-nitrobenzotrifluoride and preparation of fluoro-nitro-benzotrifluorides A process for the preparation of 3-chloro-4-fluoro-5-nitrobenzotrifluoride and 3,4-difluoro-5-nitrobenzotrifluoride by reaction of 3,4-di-chloro-5-nitrobenzotrifluoride and 4-chloro-3,5-dinitrobenzotrifluoride, respectively, with an alkali metal fluo... | 11/03/1987 |
| 4684734 | Method for manufacture or organic fluorine compounds Organic fluorine compounds such as pentafluorobenzonitrile, tetrafluorophthalonitriles, and pentafluoropyridine are produced by a method which comprises causing a chloro- or bromo-organic compound to react with a fluorinating agent such as an alkali metal... | 08/04/1987 |
| 4668830 | Process for the preparation of compounds containing a difluoromethylene or trifluoromethyl group A process for the preparation of compounds containing a difluoromethylene or trifluoromethyl group. A compound containing a carbonyl group, preferbly an acid, acid halide, amide, ketone or any compound containing a perhaloalkylcarbonyl moiety is placed, i... | 05/26/1987 |
| 4659840 | Method for preparing diaryl iodonium salts Provided is a method for preparing diaryl iodonium salts represented by the formula: wherein Ar1 and Ar2 respectively are an aryl group which may be substituted with an electron donor group and which may be the same or different whic... | 04/21/1987 |
| 4642398 | Preparation of fluoronitrobenzene compounds in dispersion of potassium fluoride An improved process is disclosed for preparing fluoronitrobenzene compounds wherein chloronitrobenzene compounds are reacted with potassium fluoride in a solvent dispersion thereof prepared from a mixture including the solvent, the fluoride, methanol and ... | 02/10/1987 |
