Sumitomo Chemical Company, Limited

Yukio Suzuki

Kohichi Aketa

Masachika Hirano

Masahiro Hayashi

Kenzi Takuma

Kiyoshi Kasamatsu

Takashi Kato

Nobuo Ohno

Seimei Yasui

Yoshinobu Matsuda

Akio Higo

Koichi Aketa

Isamu Nakayama

A method for preparing a mixture of stereoisomers of .alpha.-cyano-3-phenoxybenzyl isovalerate ester derivatives, which is rich is an enantiomer pair of a compound having an (S)-configuration on both the acid and alcohol moieties and an enantiomer thereof having an (R)-configuration on both the acid and alcohol moieties.

Method for preparing a mixture of stereoisomers of

A crystal of an enantiomer pair of stereoisomers of .alpha.-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate (general name: fenvalerate) comprising (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)isovalerate and an enantiomer thereof, which has the crystal characteristics as specified in the specification, is disclosed. A process for preparing the enantiomer pair or the fenvalerate rich in the enantiomer pair by depositing the above-described crystal from a solution of a racemate of fenvalerate is also disclosed. A process for preparing the enantiomer pair by depositing the crystal from a solution of the fenvalerate rich in the enantiomer pair is further disclosed.

Crystal of enantiomer pair of phenylacetic acid ester derivative and

A method for preparing an optically active carboxylic acid ester of the formula (I): ##STR1## wherein X is a hydrogen atom or a fluorine atom, and * indicates an asymmetric carbon atom, which is an A.alpha.-isomer having an (S)-configuration on both the acid and alcohol moieties, or rich in said A.alpha.-isomer, which method comprises crystallizing said A.alpha.-isomer from a solution of an A-isomer of the formula (I) having an (S)-configuration on the acid moiety in the presence of a crystal that is of substantially pure A.alpha.-isomer and in the presence or absence of a basic catalyst.

Method for preparing optically active carboxylic acid esters

A method for preparing (1R,cis)-2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropanecarboxylic acid useful as an acid part of practically effective insecticidal esters, which comprises reacting 2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropanecarboxylic acid containing 70% or more of the cis-form with an equimolar or less amount of (+)-1-phenyl-2-(p-tolyl)ethylamine, allowing a diastereomer salt to precipitate from a solvent, then, if necessary, purifying said salt, and decomposing said salt with a base or an acid to yield (1R,cis)-2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropanecarboxylic acid.

Method for preparing optically active

A method for preparing an optically active .alpha.-cyano-3-phenoxybenzyl 2-(4-substituted-phenyl)-isovalerate, which consists substantially of or is rich in (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-substituted-phenyl)isovalerate.

Method for preparing an optically active .alpha.-cyano-3-phenoxybenzyl

A process for isomerizing optically active .alpha.-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate at the asymmetric carbon atom of the 3-phenoxybenzyl moiety, and a process for obtaining (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)isovalerate from (R, S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)isovalerate.

Process for preparing optically active .alpha.-cyano-3-phenoxybenzyl

A method for preparing .alpha.-cyano-3-phenoxybenzyl 2-(4-substituted-phenyl)isovalerates which consist substantially of or are rich in the enantiomer pair (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-substituted-phenyl)isovalerate and (R)-.alpha.-cyano-3-phenoxybenzyl (R)-2-(4-substituted-phenyl)isovalerate.

An optically active .alpha.-cyano-3-(4-halogenophenoxy)-benzyl 2-(4-chlorophenyl)isovalerate, which consists substantially of or is rich in (S)-.alpha.-cyano-3-(4-halogenophenoxy)benzyl (S)-2-(4-chlorophenyl)isovalerate; a method for preparing the same; and an insecticidal and/or acaricidal composition containing the same.

Process for preparing optically active

A mixture of stereoisomers of an .alpha.-cyano-3-(4-halogenophenoxy)benzyl 2-(4-chlorophenyl)isovalerate, which consists substantially of or is rich in an enantiomer pair of an (S)-.alpha.-cyano-3-(4-halogenophenoxy)benzyl (S)-2-(4-chlorophenyl)isovalerate and an (R)-.alpha.-cyano-3-(4-halogenophenoxy)benzyl (R)-2-(4-chlorophenyl)isovalerate; a process for preparing the same; and an insecticidal and/or acaricidal composition containing the same.

Mixture of stereoisomers of .alpha.-cyano-3-(4-halogenophenoxy)benzyl

An .alpha.-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)isovalerate which consists substantially of or is rich in (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-chlorophenyl)isovalerate and (R)-.alpha.-cyano-3-phenoxybenzyl (R)-2-(4-chlorophenyl)isovalerate. A method for preparing the same and an insecticidal and acaricidal composition.

A process for racemization of optically active phenylacetic acid derivatives, which comprises heating an optically active phenylacetic acid derivative of the formula (I): ##STR1## wherein X and Y, which may be the same or different, each represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a halogen-substituted lower alkyl group or a halogen-substituted lower alkoxy group, or X and Y may jointly form an alkylenedioxy group; m and n, which may be the same or different, each represents an integer of 1 to 5, and the sum of m and n does not exceed 5; and R represents an isopropyl group or a cyclopropyl group, to a temperature of at least 150.degree. C. in the presence or absence of an inert solvent.

Racemization of optically active

A sulfonated product of butadiene or isoprene oligomer of the formula: ##STR1## wherein one of R.sub.1 and R.sub.1 ' is hydrogen or methyl and another one is hydrogen; R.sub.2 ' is hydrogen or methyl; one of X.sub.1 and X.sub.2 is --SO.sub.3 M and another one is hydrogen; a and b are each an integer satisfying the conditions; n = a + b, 2 &lt; n &lt; 40 and 0 &lt; b; M is hydrogen, Na, K, Li or --NR.sub.3 R.sub.4 R.sub.5 R.sub.6 ; and R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each hydrogen or an alkyl having 1 to 6 carbon atoms, which has specific properties, particularly excellent hard water resistance, and is useful for various utilities, for instance, as a surfactant, emulsifier, or the like, and a process for the production of the sulfonated product.

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Toyonaka, Japan

Yukio Suzuki