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| Number | Title | Issue Date |
| 7098371 | Method of hydrodechlorinating nuclear-chlorinated ortho-xylenes Method of hydrodechlorinating nuclear-chlorinated o-xylenes and recovering o-xylene, forming hydrogen chloride, the nuclear-chlorinated o-xylenes being hydrogenated in the gas phase at a noble-metal-containing catalyst at a temperature in the range from 220 to 360°... | 08/29/2006 |
| 7012166 | Catalyst composition and method for chlorinating aromatic compounds Aromatic compounds such as toluene and o-xylene are chlorinated in the presence of a catalyst combination prepared by combining (A) at least one salt comprising a metal selected from the group consisting of a Group 4–12 metal, a lanthanide and an actinide; and a c... | 03/14/2006 |
| 6930216 | Method for the nuclear chlorination of ortho-xylene A method for the nuclear chlorination of ortho-xylene using a chlorinating agent in the presence of at least one Friedel-Crafts catalyst and chloro-substituted 2,8-dimethylphenoxathiin as co-catalyst. The co-catalyst used is preferably tetrachlorinated 2,8-dimethylp... | 08/16/2005 |
| 6710217 | Method for producing 4-chlorobiphenyl and 4-chlorobiphenyl-specific specifications The invention relates to a process for preparing 4-chlorobiphenyl by (a) reacting biphenyl and chlorine in the presence of one or more ring-chlorination catalysts, and (b) subjecting the reaction mixture obtained in step (a) to fractional distillation ... | 03/23/2004 |
| 6426440 | Method for preparing decomposition products from the thermal decomposition of 1,2-dichlorethane The work-up of the gaseous products from the thermal cracking of 1,2-dichloroethane is simplified if the cracking gases are cooled to a temperature range of about 150 to 180° C., only a subsidiary proportion, which comprises all the coke formed, being co... | 07/30/2002 |
| 6271426 | Process for the production of 2,6-dichloro-3,5-di(secondary or tertiary alkyl)toluene This invention relates to an improved process for producing 2,6-dichloro-3,5-di(secondary or tertiary alkyl)toluene represented by the following formula (I). The process comprises chlorinating 3,5-di(secondary and tertiary alkyl)toluene represented by the... | 08/07/2001 |
| 6222079 | Method of increasing certain isomeric ratios in chlorinating substituted benzenes Disclosed is a method of increasing the percentage of certain isomers made when di or tri-substituted benzenes are chlorinated in the presence of a Friedel-Crafts catalyst. The use of about 0.001 to about 1 wt % a cocatalyst during chlorination alters the... | 04/24/2001 |
| 6156945 | Method of making high purity 2,4- and 3,4-dichlorotoluene Disclosed is a method of making high purity 2,4- and 3,4-dichlorotoluene from parachlorotoluene that contains some metachlorotoluene. About 0.0001 to about 5 wt % of a Friedel-Crafts catalyst and about 0.5 to about 10 equivalents of a brominating agent ar... | 12/05/2000 |
| 6117278 | Method of making -chloroxylenes Disclosed is a method for making high purity -chloroxylenes. A composition is formed of about 15 to about 80 wt % of a xylene and about 20 to about 85 wt % of a solvent. The solvent can be toluene, ring halogenated toluene, benzotrichloride, ring h... | 09/12/2000 |
| 5710355 | Method of making chlorobenzenes Disclosed is a method of making a chlorobenzene having the general formulas ##STR1## where X is Cl or F, and X' is X or CF3. A compound having the formula ##STR2## is sulfonated using at least 2 moles per mole of said compound of a su... | 01/20/1998 |
| 5621153 | Process for the preparation of chloro-alkylbenzenes and novel cocatalysts therefor A process for the para-directed nuclear chlorination of an alkylbenzene, such as toluene, comprises reacting the alkylbenzene with chlorine in the presence of a Lewis acid catalyst and a novel co-catalyst of the formula: ##STR1## where Z is ##ST... | 04/15/1997 |
| 5210343 | Process for the preparation of p-dichlorobenzene Dichlorobenzene having an increased p-content and a greatly reduced m-content is obtained by ring chlorination of benzene or chlorobenzene in the presence of Friedel-Crafts catalysts if the reaction is carried out in the presence of co-catalysts of the fo... | 05/11/1993 |
| 5107045 | Preparation of 4-bromo-O-xylene using excess bromine A regioselective process is provided for preparing 4-bromo-o-xylene in an isomer mixture of 4-bromo-o-xylene and 3-bromo-o-xylene by combining a molar excess of bromine with o-xylene. The produced 3-bromo-o-xylene isomer preferentially reacts with the exc... | 04/21/1992 |
| 5105036 | Process for ring-chlorination of aromatic hydrocarbons Aromatic hydrocarbons monosubstituted by straight-chain or branched C1 -C12 -alkyl or by Chd 3-C8 -cycloalkyl can be chlorinated in the aromatic ring in the liquid phase in the presence of Friedel-Crafts catalysts if cycli... | 04/14/1992 |
| 5095157 | Process for the preparation of 2-chloro-4-nitro-alkylbenzene In the preparation of 2-chloro-4-nitro-alkylbenzene by reaction of 4-nitro-alkylbenzene with elemental chlorine or chlorine-releasing compounds in the presence of a Friedel-Crafts catalyst in the liquid phase, particularly high selectivities in respect of... | 03/10/1992 |
| 5030777 | Synthesis of 3,5-dichloroalkylbenzene and recovery of 1,3-dichlorobenzene A process for synthesizing 3,5-dichloroalkylbenzene and recovering 1,3-dichlorobenzene from a starting mixture of 1,3- and 1,4-dichlorobenzenes. The process includes the sequential steps of selectively alkylating the 1,3-dichlorobenzene in the starting mi... | 07/09/1991 |
| 5026932 | Preparation of 4-bromo-o-xylene in liquid sulfur dioxide A regioselective process is provided for preparing 4-bromo-o-xylene in an isomer mixture of 4-bromo-o-xylene and 3-bromo-o-xylene by combining bromine with o-xylene in liquid sulfur dioxide medium. A bromine to o-xylene mole ratio of about 0.4:1 to about ... | 06/25/1991 |
| 5015792 | Preparation of 4,4'-dibromobiphenyl 4,4'-Dibromobiphenyl is selectively produced in high yields by actively brominating biphenyl in a reaction medium containing at least one strong acid having a pKa of at most 4, e.g., a carboxylic or sulfonic acid, and, optionally, a reaction solvent.... | 05/14/1991 |
| 4990707 | Process for the ring chlorination of aromatic hydrocarbons Aromatic hydrocarbons which are monosubstituted by straight-chain or branched C1 -C12 -alkyl or by C3 -C8 -cycloalkyl can be chlorinated in the presence of Friedel-Crafts Catalysts in liquid phase on the aromati... | 02/05/1991 |
| 4925994 | Process for the ring chlorination of aromatic hydrocarbons Aromatic hydrocarbons which are monosubstituted by straight-chain or branched C1 -C12 -alkyl or by C3 -C8 -cycloalkyl can be chlorinated in the presence of Friedel-Crafts Catalysts in liquid phase on the aromati... | 05/15/1990 |
| 4891455 | Process for preparing monohalogenated cyclobutarenes Monohalogenated cyclobutarenes are prepared by halogenating a cyclobutarene in the presence of an organic complexing agent, an acid scavenger, or water. Faster reaction rates highly selective to monohalogenated cyclobutarenes are obtained without conventi... | 01/02/1990 |
| 4861929 | Process for producing halogenated benzene derivative using zeolite catalyst A p-substituted halobenzene derivative, which is very valuable in industry, can be obtained by halogenation of benzene and/or a benzene derivative in the liquid phase using, as a catalyst, a faujasite type zeolite in the presence of any one member selecte... | 08/29/1989 |
| 4851596 | Process for nucleus-chlorination of aromatic hydrocarbons Aromatic hydrocarbons are chlorinated in the nucleus in the presence of Friedel-Crafts catalysts and in the presence of co-catalysts in the liquid phase by using thiazepines as co-catalysts.... | 07/25/1989 |
| 4822930 | Process for preparing monobrominated cyclobutarenes Monobrominated cyclobutarenes are prepared by brominating a cyclobutarene in the presence of an organic complexing agent, an acid scavenger, or water. Faster reaction rates highly selective to monobrominated cyclobutarenes are obtained without conventiona... | 04/18/1989 |
| 4822928 | Process for producing 2,5-dichlorotoluene Disclosed herein is a process for producing 2,5-dichlorotoluene which is useful as a monomer of heat-resistant polymers and an intermediate raw material for medicines, agricultrual chemicals and various organic synthetic substances, the process giving 2,5... | 04/18/1989 |
| 4748287 | Process for the removal of m-dichlorobenzene from dichlorobenzene mixtures The invention relates to a process for the removal of m-dichlorobenzene from dichlorobenzene mixtures by chlorination in the liquid phase at elevated temperature in the presence of Friedel-Crafts catalysts, the chlorination being carried out with addition... | 05/31/1988 |
| 4740641 | Producing a halogenated benzene derivative using zeolite catalyst treated with alkali solution of pH 11 or more A p-substituted halobenzene derivative, which is very valuable in industry, can be obtained by halogenation of benzene and/or a benzene derivative in a liquid phase at a temperature of 0° to 200° C. at a higher selectivity and yield than in known proces... | 04/26/1988 |
| 4647709 | Process for ring-chlorinating toluene In the ring chlorination of toluene, a particularly high proportion of p-chlorotoluene is obtained by using in addition to the customary Lewis acid catalysts as cocatalyst a chlorination product of 2,8-dimethylphenoxathiin which comprises in the main ... | 03/03/1987 |
| 4613698 | Process for the preparation of 6-chloro-2,4-dinitroaniline Process for the preparation of 6-chloro-2,4-dinitroaniline by chlorination of 2,4-dinitroaniline with sodium hypochlorite in water using acid, which comprises carrying out the chlorination in the presence of a mineral acid or strong organic acid at a pH v... | 09/23/1986 |
| 4444983 | Process for the nuclear chlorination of toluene Para-chlorotoluene is prepared selectively at high yield by nuclear chlorination of toluene, in the presence of a Lewis acid catalyst, and a co-catalyst comprising at least one compound selected from the group consisting of phenoxthine derivatives and hig... | 04/24/1984 |
| 4417081 | Selective 2-chlorination of meta-dihalobenzenes The meta-dihalobenzenes are selectively 2-chlorinated by reacting same with a chlorine donor, e.g., hexachlorobenzene or pentachlorobenzene, in the presence of at least one alkali metal amide, e.g., sodamide, and at least one compound which complexes the ... | 11/22/1983 |
| 4351975 | Process for preparing chlorinated compounds A process for the preparation of monochlorinated and dichlorinated bis-(perhalomethyl)-benzenes of the formula (I) by reacting bis-(perhalomethyl)-benzenes of the formula (II) with elementary chlorine in chlorosulfonic acid as the reaction medium, at a te... | 09/28/1982 |
| 4327036 | Chlorination process Process for nuclear chlorination of non-phenolic aromatic compounds, said process comprising contacting and reacting a non-phenolic aromatic compound having a net Hammett ς value of about -0.1 to about 2.0 with chlorine monoxide in the presence of at lea... | 04/27/1982 |
| 4289916 | Process for producing p-chloroalkylbenzene p-Chloroalkylbenzene is selectively produced by chlorinating an alkylbenzene in the presence of a phenoxthine compound having the formula ##STR1## wherein X1, X2, X3 and X4 are the same or different and res... | 09/15/1981 |
| 4250122 | Process and catalyst mixture for the para-directed chlorination of alkylbenzenes A process for the para-directed chlorination of alkylbenzenes comprises reacting an alkylbenzene with chlorine in the presence of a catalyst mixture previously prepared by the steps of (a) reacting sulfur monochloride with toluene or chlorotoluene in the ... | 02/10/1981 |
| 4191711 | Process for the preparation of certain nuclear chlorinated benzotrichlorides A process for the preparation of 3,4-dichlorobenzotrichloride, 3,4,5-trichlorobenzotrichloride, 2,4,5-trichlorobenzotrichloride or 2,3,4,5-tetrachlorobenzotrichloride which comprises contacting p-chlorobenzotrichloride of the formula ##STR1## wi... | 03/04/1980 |
| 4190609 | Process for the directed chlorination of xylenes A process for the production of nuclear chlorinated alkylbenzenes comprises reacting xylene with chlorine in the presence of a Lewis acid catalyst and a co-catalyst comprising a thianthrene compound or a mixture of thianthrene compounds characterized by t... | 02/26/1980 |
| 4069264 | Process for directed chlorination of alkylbenzenes A process for the production of nuclear chlorinated alkylbenzenes comprises reacting, in the liquid phase, alkylbenzene with chlorine in the presence of a Lewis acid catalyst and a co-catalyst comprising a thianthrene compound or mixture of thianthrene co... | 01/17/1978 |
| 4069263 | Process for directed chlorination of alkylbenzenes A process for the production of nuclear chlorinated alkylbenzenes comprises reacting, in the liquid phase, alkylbenzene with chlorine in the presence of a Lewis acid catalyst and a co-catalyst comprising a thianthrene compound or mixture of thianthrene co... | 01/17/1978 |
| 4031145 | Process for the production of 3,4-dichlorotoluene Dichlorotoluene that contains at least 35 percent of 3,4-dichlorotoluene is prepared by contacting para-chlorotoluene with chlorine in the presence of a chlorination catalyst that is either a metal sulfide or a mixture of a ring-chlorination catalyst and ... | 06/21/1977 |
