Patents Assigned to Koei Chemical Co., Ltd.
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Patent number: 7342116Abstract: A process is disclosed for preparing a heterocyclic aldehyde by oxidizing a heterocyclic alcohol with high selectivity and high yield. Specifically, the heterocyclic aldehyde is prepared by reacting a heterocyclic compound having at least one hydroxymethyl group bonded to a carbon atom of a heterocyclic ring with a hypohalogenous acid salt in the presence of a base to oxidize the hydroxymethyl group, wherein reaction is conducted in the co-presence of a 2,2,6,6-tetramethylpiperidine-1-oxyl derivative having at least two 2,2,6,6-tetramethylpiperidine-1-oxyl-4-yl groups.Type: GrantFiled: March 25, 2003Date of Patent: March 11, 2008Assignee: Koei Chemical Co., Ltd.Inventors: Yasuhiro Shiomi, Osamu Uno, Akio Ohta, Takeshi Sunakami
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Patent number: 6444815Abstract: There is provided a process for preparing a heteroaromatic aldehyde by catalytic reaction of alkyl-substituted heteroaromatic compound with molecular oxygen in a gaseous phase in the presence of a catalyst, which comprises employing an oxide containing vanadium, phosphorus, aluminium and silicon as a catalyst, and diluting a part or all of the oxide present as a catalyst layer in a reactor with a solid inert to the reaction.Type: GrantFiled: August 18, 2000Date of Patent: September 3, 2002Assignee: Koei Chemical Co., Ltd.Inventors: Tetsushi Nishiyama, Toru Nakaishi, Takayuki Shoji
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Patent number: 6271382Abstract: An organic compound having a nitroxide free radial of the formula (2) is prepared by reacting a cyclic secondary amine having a steric hindrance of the formula (1) with a peroxide in the presence of at least 1 part by weight of an organic compound having a cyano group per 1 part by weight of the cyclic secondary amine having the steric hindrance. In the formulae (1) and (2), T is a methylene group, an ethylene group, an oxygen atom or a methyleneoxy group; R is an alkyl group, an aralkyl group, an aryl group, a cycloalkyl group, an alkoxy group, an acyl group an acyloxy group, an amino group, a hydroxyl group or a heterocyclic group; R1, R2, R3 and R4 are the same or different and each an alkyl group or an aryl group, or R1 and R2 and/or R3 and R4 together form a tetramethylene group or a pentamethylene group; and n is an integer of 0 to 6.Type: GrantFiled: August 28, 2000Date of Patent: August 7, 2001Assignee: Koei Chemical Co., Ltd.Inventor: Katsuhiro Iwazaki
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Patent number: 6197961Abstract: At least one of a Rh catalyst, a Pd catalyst or a Ru catalyst is used as a catalyst in preparing the salt of &ggr;-(piperidyl)-butyric acid (2) by hydrogenating the salt of &ggr;-(pyridyl)butyric acid (1) [preferably the salt of &ggr;-(pyridyl)butyric acid (1) obtained in the undermentioned steps (a) and (b) and containing not more than 3% by weight of salt of bis(pyridylethyl)acetic acid (3)] in a solvent in the presence of a catalyst: (a) reacting the vinylpyridine (4) with the diester of malonic acid (5) in the presence of a base to give the 2-(pyridylethyl)malonic acid diester (6), and (b) hydrolyzing and decarboxylating the 2-(pyridylethyl)malonic acid diester (6) obtained in the step (a) in an acidic aqueous solution to give the salt of &ggr;-(pyridyl)butyric acid (1).Type: GrantFiled: June 4, 1998Date of Patent: March 6, 2001Assignee: Koei Chemical Co., Ltd.Inventors: Toshito Sakai, Masayo Nagaoka, Ken Kanno
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Patent number: 6111113Abstract: 2,3,5-Collidine and 2-ethyl-5-methylpyridine are prepared in high yields at the same time by reacting methacrolein and methyl ethyl ketone with ammonia in a gas phase in the presence of a catalyst which comprises silica-alumina containing at least one element selected from the group consisting of cobalt, zinc, cadmium, thallium and lead.Type: GrantFiled: June 12, 1998Date of Patent: August 29, 2000Assignee: Koei Chemical Co., Ltd.Inventors: Naorou Itoh, Nobuyuki Abe
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Patent number: 5922873Abstract: A process for preparing a N-tert-butyl-2-pyrazinecarboxamide having the formula (2): ##STR1## which comprises reacting a cyanopyrazine having the formula (1): ##STR2## with tert-butyl alcohol in the presence of sulfuric acid and a process for preparing a N-tert-butyl-2-piperazine-carboxamide having the formula (3): ##STR3## which comprises hydrogenating of said N-tert-butyl-2-pyrazinecarboxamide having the formula (2) in the presence of Raney nickel or Raney cobalt.Type: GrantFiled: January 20, 1998Date of Patent: July 13, 1999Assignee: Koei Chemical Co., Ltd.Inventors: Nanao Watanabe, Sadao Asahi, Hideki Kuranishi
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Patent number: 5734055Abstract: A process for preparing a N-tert-butyl-2-pyrazinecarboxamide having the formula (2): ##STR1## which comprises reacting a cyanopyrazine having the formula (1): ##STR2## with tert-butyl alcohol in the presence of sulfuric acid and a process for preparing a N-tert-butyl-2-piperazine-carboxamide having the formula (3): ##STR3## which comprises hydrogenating of said N-tert-butyl-2-pyrazinecarboxamide having the formula (2) in the presence of Raney nickel or Raney cobalt.Type: GrantFiled: July 20, 1995Date of Patent: March 31, 1998Assignee: Koei Chemical Co. Ltd.Inventors: Nanao Watanabe, Sadao Asahi, Hideki Kuranishi, Takashi Kurahashi
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Patent number: 5693806Abstract: A process for producing a pyrazine compound of the general formula (3): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 represent a hydrogen atom or a lower alkyl group, which comprises catalytically reacting in a gaseous phase a diamine compound of the general formula: ##STR2## with a diol compound of the general formula: ##STR3## in the presence of a catalyst containing hydrogen-treated silver or a catalyst containing silver and at least one element selected from the group consisting of alkali metals, alkaline earth metals, zinc and lanthanoid elements.Type: GrantFiled: July 23, 1996Date of Patent: December 2, 1997Assignee: Koei Chemical Co., Ltd.Inventors: Takayuki Shoji, Toru Nakaishi, Masafumi Mikata
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Patent number: 5668281Abstract: A process for preparing a tertiary amine-N-oxide which comprises reacting a tertiary amine with a peroxide in the presence of a catalyst comprising an oxide containing silicon and titanium atoms. According to the process of the present invention, a tertiary amine-N-oxide can be obtained in a high yield, and since the catalyst can easily be separated from the reaction mixture, the tertiary amine-N-oxide can be obtained in a high purity without the contamination by the catalyst.Type: GrantFiled: January 19, 1996Date of Patent: September 16, 1997Assignee: Koei Chemical Co., Ltd.Inventors: Shinkichi Shimizu, Nanao Watanabe, Hideki Kuranishi
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Patent number: 5496949Abstract: This invention is to provide a pyrazine derivative capable of developing excellent therapeutic efficacy in infectious diseases caused by various acid-fast bacteria.The pyrazine derivative of this invention is represented by the general formula ##STR1## wherein R.sub.1 is an octyl group or a pivaloyloxymethyl group.Type: GrantFiled: October 19, 1994Date of Patent: March 5, 1996Assignee: Koei Chemical Co., Ltd.Inventors: Ichiro Toida, Setsuko Yamamoto, Nanao Watanabe, Toshikazu Ura
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Patent number: 5424437Abstract: A 2-Chloro-5-aminomethylpyridine is prepared in one step by reacting 2-chloro-5-trichloromethylpyridine with an amine and hydrogen in the presence of a hydrogenation catalyst.Type: GrantFiled: January 31, 1994Date of Patent: June 13, 1995Assignee: Koei Chemical Co., Ltd.Inventors: Katsuhiro Ieno, Yoshihiro Kawanami
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Patent number: 5300650Abstract: A process for producing an aminomethylpyridine having a chlorine atom at the .alpha.-position, for example, 2-chloro-5-aminomethylpyridine by subjecting a cyanopyridine having a chlorine atom at the .alpha.-position, for example, 2-chloro-5-cyanopyridine, to a catalytic reduction in the presence of a tertiary amine in a non-aqueous reaction system.With the process, the removal of the chlorine atom bonding to the .alpha.-position can be depressed and an aminomethylpyridine having a chlorine atom at the .alpha.-position can be produced at a high yield.Type: GrantFiled: September 25, 1992Date of Patent: April 5, 1994Assignee: Koei Chemical Co., Ltd.Inventor: Toshinari Nabata
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Patent number: 5208380Abstract: A process for preparing monoallylamine represented by the formula (II):CH.sub.2 .dbd.CHCH.sub.2 NH.sub.2 (II)which comprises: catalytically reacting isopropanolamine represented by the formula (I): ##STR1## in a gaseous phase in the presence of a catalyst having dehydrating property. According to the preparation process of the present invention, monoallylamine can be easily obtained in high selectivity and high yield.Type: GrantFiled: April 13, 1992Date of Patent: May 4, 1993Assignee: Koei Chemical Co., Ltd.Inventors: Shinkichi Shimizu, Takayuki Shoji, Hideki Nakao
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Patent number: 5180792Abstract: Disclosed is a curable epoxy resin composition which is effectively cured at ambient temperature and when cured has excellent adhesive strength and good water resistance. The epoxy resin composition comprises:(a) an epoxy resin having at least two epoxy groups in one molecule,(b) a monofunctional (meth)acrylate represented by ##STR1## wherein R.sub.1 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, R.sub.2 and R.sub.3 respectively represent a hydrogen atom or a methyl group, and n is an integer of 1 to 4, and(c) An amine curing agent selected from the group consisting of an aromatic polyamine, a modified aromatic polyamine, a polyamideamine and a mixture thereof. The present invention also provides an adhesive composition prepared from the above mentioned curable epoxy resin composition.Type: GrantFiled: February 20, 1991Date of Patent: January 19, 1993Assignee: Koei Chemical Co., Ltd.Inventors: Tetuzi Takada, Nobuo Gotoh
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Patent number: 5114604Abstract: A curable resin binder comprising an epoxy resin which is a solid at room temperature, an epoxy resin curing agent which is inactive at room temperature, and as a curing accelerator, a pyridine derivative containing at least one hydroxyl group in a molecule. Also disclosed is a resin-bonded rare earth permanent magnet made by employing the binder and a powder of an alloy containing a rare earth metal or metals.Type: GrantFiled: November 22, 1989Date of Patent: May 19, 1992Assignees: Koei Chemical Co., Ltd., Sumitomo Metal Mining Co., Ltd.Inventors: Junichi Ishii, Tetsuji Takada, Takayuki Kurohara
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Patent number: 4931561Abstract: A heteroaromatic nitrile is prepared in high conversion and yield by catalytically reacting an alkyl-substituted heteroaromatic compound with molecular oxygen and ammonia in the presence of a catalyst having the following composition:Mo(P).sub.x (A).sub.y (B).sub.z (O).sub.w (I)wherein x, y, z and w represent atomic ratios of phosphorus, an element A defined below, an element B defined below and oxygen to molybdenum, respectively and(i) x and z are both 0 (zero), y is from 0.1 to 5, and A is at least one element selected from the group consisting of cerium and tungsten, or(ii) x is from 0.1 to 7, y is from 0 to 5, z is from 0 to 5, A is at least one element selected from the group consisting of cerium, manganese and tungsten, and B is at least one element selected from the group consisting of thallium, titanium, niobium and aluminum, or(iii) x is from 0.5 to 7, y is from 0 to 5, z is from 0.01 to 2.Type: GrantFiled: July 25, 1988Date of Patent: June 5, 1990Assignee: Koei Chemical Co., Ltd.Inventors: Shinkichi Shimizu, Takayuki Shoji, Kanji Kono, Toru Nakaishi
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Patent number: 4910270Abstract: Disclosed is a curable epoxy resin composition having excellent flexibility and toughness, comprising (a) an epoxy resin, (b) a glycol type di(meth)acrylate, (c) a nitrogen containing heterocyclic compound, and (d) a polyamine having at least two amino groups with an active hydrogen. The resin composition is very suitable for a vibration damping laminate.Type: GrantFiled: September 12, 1988Date of Patent: March 20, 1990Assignee: Koei Chemical Co., Ltd.Inventors: Zenichiro Maekawa, Kazuo Uede, Shinichi Yasuda, Tetsuzi Takata, Yosiaki Turuta
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Patent number: 4812566Abstract: Disclosed is a process for preparing 1-dodecylazacyclo-heptane-2-one, the process comprising reacting azacylcloheptane-2-one with dodecyl halide in a substantially non-aqueous system in the presence of a phase-transfer catalyst represented by the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are alkyl or aralkyl, or two or three of the groups R.sub.1, R.sub.2, R.sub.3 and R.sub.4, when taken together with nitrogen to which they are attached, form a heterocyclic group (in which case the remaining one or two of the groups being alkyl or aralkyl) and X.sup..crclbar. is a univalent anion.Type: GrantFiled: December 17, 1987Date of Patent: March 14, 1989Assignee: KOEI Chemical Co., Ltd.Inventor: Toshinari Nabata
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Patent number: 4810794Abstract: Process for producing pyridine bases by reacting an aliphatic aldehyde and/or ketone with ammonia in gaseous phase in the presence of a catalyst, characterized by using a catalyst which is obtained by modifying a zeolite having an atomic ratio of Si to Al, Fe and/or Ga of 12 to 1,000 and a constraint index of about 0.8 to about 12 with at least one metal ion and/or metal compound selected from the group consisting of thallium, lead and cobalt.Type: GrantFiled: February 2, 1987Date of Patent: March 7, 1989Assignee: Koei Chemical Co., Ltd.Inventors: Shinkichi Shimizu, Nobuyuki Abe, Masanori Doba, Akira Iguchi, Hiroshi Sato, Ken-ichi Hirose, Youichi Umada
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Patent number: 4778890Abstract: A heteroaromatic nitrile is prepared in a high selectivity and yield by catalytically reacting an alkyl-substituted heteroaromatic compound with molecular oxygen and ammonia in a molar ratio of oxygen to ammonia of not larger than 1.6:1 in a gaseous phase in the presence of a catalyst comprising a vanadium-phosphorus oxide of the formula:VP.sub.x Sb.sub.y O.sub.z (I)wherein x, y and z represent atomic ratios of phosphorus, antimony and oxygen to vanadium, respectively, and x is from 0.1 to 5, y is 0 to 8 and z is defined from the valencies of other elements.Type: GrantFiled: July 16, 1987Date of Patent: October 18, 1988Assignee: Koei Chemical Co., Ltd.Inventors: Shinkichi Shimizu, Takayuki Shoji, Nobuyuki Abe, Masanori Doba, Akira Taguro, Akira Iguchi, Toru Nakaishi