Kureha Chemical Industry Company, Limited

Kureha Kagaku Kogyo Kabushiki Kaisha

Kureha Corporation

Kureha Kagaku Kogyo K.k.

Hajime Hoshi

Kazuhiko Sunagawa

Satoru Kumazawa

Yukichika Kawakami

Kazuyuki Yamane

Nobuyuki Kusano

Takeo Watanabe

Shigeru Mizusawa

Tsumoru Watanabe

5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone is produced by

Process for the preparation of 5-[(4-chlorophenyl)methyl]-2,2-dimethylcyclopentanone

The present invention provides a process for production of a cyclic ester by depolymerization of an aliphatic polyester. In the process, a mixture containing the aliphatic polyester and a specific polyalkylene glycol ether, which has a boiling point of 230-450&#xb0; C. and a molecular weight of 150-450, is heated under normal or reduced pressure to a temperature at which depolymerization of the aliphatic polyester takes place. Then, a substantially homogeneous solution phase, consisting of the melt phase of the aliphatic polyester and the liquid phase of the polyalkylene glycol ether, is formed. Heating of the solution phase is continued to form the cyclic ester by depolymerization and distil out the cyclic ester together with the polyalkylene glycol ether, and then the cyclic ester is recovered from the distillate. The present invention also provides a process for purification of a crude cyclic ester by use of the specific polyalkylene glycol ether described above.

Process for the preparation of cyclic esters and method for purification of the same

The present invention provides a process for producing alkylcyclopentanone derivatives of formula (1) by reacting alkyl cyclopentanone derivatives of formula (2) and alkyl halides of formula (3) in an organic solvent in the presence of molecular sieves and an alkaline metal hydroxide: ##STR1## wherein R.sup.1 is C.sub.1 -C.sub.4 alkyl group; R.sup.2 is hydrogen atom or C.sub.1 -C.sub.5 alkyl group; R.sup.3 is C.sub.1 -C.sub.5 alkyl group; Y is halogen atom, C.sub.1 -C.sub.5 alkyl group, C.sub.1 -C.sub.5 haloalkyl group, phenyl group, cyano group or nitro group; n is an integer from 0 to 5; when n is 2 or greater, Y's may be identical or different; R.sup.3 in formula (3) is the same as R.sup.3 in formula (1); and a process for preparing alkylcyclopentanone derivatives of formula (5) by reacting cyclopentanone derivatives of formula (4) and alkyl halides of formula (6) in an organic solvent in the presence of molecular sieves and an alkaline metal hydroxide: ##STR2## wherein R.sup.1 is C.sub.1 -C.sub.4 alkyl group; R.sup.4 is hydrogen atom or C.sub.1 -C.sub.5 alkyl group; R.sup.5 is C.sub.1 -C.sub.5 alkyl group; R.sup.k is either R.sup.4 or R.sup.5 ; Y is halogen atom, C.sub.1 -C.sub.5 alkyl group, C.sub.1 -C.sub.5 haloalkyl group, phenyl group, cyano group or nitro group; n is an integer from 0 to 5; when n is 2 or greater, Y's may be identical or different.

Process for the producing of alkylcyclopentanone derivatives

A process for manufacturing derivatives of 2-phenyl-4,5-oxazoledione 4-phenylhyrazone is disclosed. The process comprises reacting a derivative of a benezenediazonium salt, a hippuric acid derivative, and acetic anhydride in the presence of a neutralizing agent to effect the cyclization reaction for the formation of the oxazolone ring and the succeeding diazo-coupling reaction. The process does not require the conventional separate, independent step for the preparation of a solution of a hippuric acid derivative and acetic anhydride, thus eliminating the quick heating and quenching procedures and further avoiding the loss of the hippuric acid derivative due to decomposition of the oxazolone derivative. There is thus obtained a high yield of the desired product in a short period of time.

Process for the manufacture of 2-phenyl-4,5-oxazoledione

A process for chlorination of methylated aromatic compounds in a titanium tetrachloride is disclosed. The ring chlorination is first carried out by reacting said methylated aromatic compounds with chlorine gas under reduced light conditions, and then the side chain chlorination is carried out by reacting the resulting mixture with chlorine gas under light irradiation conditions. The process ensures continuous chlorination of aromatic rings and side chains of methylated aromatic compounds at a high yield without using any catalysts or perilous solvents such as carbon tetrachloride.

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Fukushima, Japan

Hajime Hoshi