Kureha Kagaku Kogyo Kabushiki Kaisha

Kureha Kagaku Kogyo K.k.

Shoichiro Hayashi

Yutaka Konai

Atsushi Sasakawa

Toshiharu Matsuda

Takashi Yamauchi

Akira Iizuka

Kouichi Kodama

Masakatsu Wagu

Tadashi Nakamura

Teruo Sakagami

Naohiro Murayama

Satoru Kumazawa

Yoshikazu Kubota

Kazuhiko Sunagawa

A process for separating a cis isomer from a mixture of the cis isomer and a trans isomer of an azolylmethylcyclopentanol derivative of the formula (I): ##STR1## wherein, R.sup.1 and R.sup.2 each independently represent a hydrogen atom or an alkyl group; each X represents a halogen atom, an alkyl group, a haloalkyl group, a phenyl group, a cyano group or a nitro group; n is an integer of from 0 to 5; A represents a nitrogen atom or a CH group; and each X may be identical or different when n is an integer of from 2 to 5, comprising the steps of dehydrating selectively the trans isomer in the presence of an acid and isolating the cis isomer.

Process for separating isomers of azolylmethylcyclopentanol derivatives

Biphenyl-4,4'-dicarboxylic acid is prepared by isolating a mixture of diisopropylbiphenyls from a reaction mixture obtained by reacting biphenyl with propylene, crystallizing 4,4'-diisopropylbiphenyl from the mixture of diisopropylbiphenyls, and oxidizing 4,4'-diisopropylbiphenyl or an oxidation intermediate thereof with molecular oxygen in the presence of an oxidation catalyst, which comprises a cobalt catalyst and/or manganese catalyst, in a solvent containing at least 50 wt. % of an aliphatic mono- carboxylic acid having up to 3 carbon atoms.

Preparation process of biphenyl-4,4'-dicarboxylic acid

Disclosed in the present invention is a process for producing 2,6-naphthalenedicarboxylic acid comprising oxidizing 2,6-diisopropylnaphthalene or its partially oxidized intermediate with molecular oxygen in a solvent containing at least 50% by weight of an aliphatic monocarboxylic acid, having not more than three carbon atoms, in the presence of a catalyst composed of (i) a heavy metal comprising cobalt and/or manganese and (ii) bromine, and a salt of an inorganic acid having an acid dissociation constant Ka smaller than 1.34.times.10.sup.-5 (at 25.degree. C.) and a vapor pressure lower than that of the aliphatic monocarboxylic acid used as the solvent. According to the process of this invention, 2,6-naphthalenedicarboxylic acid of high bulk density can be obtained in a high yield and with high purity.

Process for producing 2,6-naphthalenedicarboxylic acid

Disclosed herein is a process for producing a highly pure produce of 2,6-naphthalenedicarboxylic acid in a large quantity at a moderate price by oxidizing 2,6-diisopropylnaphthalene while using a water-soluble salt of cobalt, a water-soluble salt of maganese or a mixture thereof, a water-soluble salt of cerium and a bromine compound as the catalyst of the oxidation.

Process for producing 2,6-naphthalenedicarboxylic acid by oxidizing

Disclosed herein is a process for producing 2,6-naphthalenedicarboxylic acid together with trimellitic acid comprising oxidizing 2,6-diisopropylnaphthalene with molecular oxygen in the presence of a catalyst comprising a heavy metal(s) and bromine.

Process for producing naphthalenedicarboxylic acid together with

Disclosed herein is a process for producing 2,6-naphthalenedicarboxylic acid, comprising (1) oxidizing 2,6-diisopropylnaphthalene in a lower fatty acid as a solvent in the presence of a catalyst comprising a water-soluble cobalt salt and/or a water-soluble manganese salt in an amount of at least 0.5 gram-atom of Co and/or Mn to 1 mol of 2,6-diisopropylnaphthalene by an oxygen-containing gas, thereby obtaining isopropylnaphthalene-monocarboxylic acid and (2) further oxidizing the thus obtained 6-isopropyl-2-naphthoic acid in the lower fatty acid in the presence of the catalyst comprising a water-soluble cobalt salt and/or a water-soluble manganese salt in an amount of from 0.0025 to 0.12 gram-atom to 1 mol of 6-isopropyl-2-naphthoic acid by the oxygen-containing gas, thereby obtaining 2,6-naphthalenedicarboxylic acid.

Disclosed herein are the novel 6-substituted naphthalene-2-carboxylic acids represented by the formula (I): ##STR1## wherein X represents a hydroperoxy group or a hydroxy group, and a process for producing the 6-substituted naphthalene-2-carboxylic acid represented by the formula (I) by reacting 6-isopropylnaphthalene-2-carboxylic acid with molecular oxygen under heating in the presence of a salt of persulfuric acid as a catalyst in an aqueous alkaline solution.

6-substituted naphthalene-2-carboxylic acids and process for producing

Disclosed herein is a process for producing i-brassicasterol, comprising charging a mixture of i-sterols derived from a mixture of sterols including brassicasterol into a column packed with a filler obtained by chemically binding alkyl group(s) of 15 to 24 carbon atoms to silica, and subjecting said mixture of i-sterols to reversed-phase partition column-chromatography while using (i) an alcohol of one to three carbon atoms or a mixture therof, or (ii) a mixed solvent comprising more than 50% by volume of said alcohol(s) and a solvent other than said alcohol(s) as an eluent, thereby isolating and purifying i-brassicasterol.

Process for producing i-brassicasterol

Disclosed herein are methyl 2-(2-hydroperoxy-2-propyl)naphthalene-6-carboxylate represented by the formula (I): ##STR1## and a process for producing the compound represented by the formula (I) at a high purity and in a high yield.

Methyl 2-(2-hydroperoxy-2-propyl)naphthalene-6-carboxylate and process

A substrate for liquid chromatography comprising a spherical particle of highly cross-linked polymer which is produced from (a) 100 parts by weight of a monomer of vinyl ester, acrylate or methacrylate, these esters having a long alkyl chain, if desired, together with a comonomer copolymerizable with the monomer and (b) 10 to 80 parts by weight of a cross-linking agent copolymerizable with the monomer and having at least two functional groups, and a process for isolating and purifying a fat-soluble substance, for instance, a lower alkyl ester of eicosapentaenoic acid or docosahexaenoic acid by means of the liquid chromatography on the substrate.

Substrate for liquid chromatography and process for isolating and

This disclosure describes an inclusion compound of cyclodextrin in which at least one guest compound selected from the group of eicosapentaenoic acid, docosahexaenoic acid and alkali metal salts and alkyl esters thereof is included.

Growing community of inventors

Iwaki, Japan

Shoichiro Hayashi