Hoechst Aktiengesellschaft

Hoechst Schering Agrevo Gmbh

Harald Knorr

Hilmar Mildenberger

Lothar Willms

Hartmut Wiezer

Norbert Mayer

Gunter Schlegel

Herbert Stark

Gerhard Pfahler

Gerhard Schnabel

Reinhard Handte

Thomas Maier

Arno Schulz

Klemens Minn

Gerhard Salbeck

Jan Vermehren

Hans J Nestler

Helmut Korbanka

Heribert Tetzlaff

Rainer Schutze

Thomas Tammer

4-jod-2[N-(N-alkyl-aminocarbonyl)-aminosulfonyl]-benzoic acid methyl

Disclosed and claimed is a process for the preparation of a carbamate (IV)

Process for the preparation of herbicidal sulfonylureas and of

The title compounds are obtained by racemate resolution of D,L-homoalanin-4-yl(methyl)phosphinic acid via precipitation of one of the diastereomeric salts using chiral bases such as quinine or cinchonine. It is possible to increase the yield of desired enantiomer by transformed racemate resolution when the precipitation of the diastereomeric salt takes place with the racemization of the undesired enantiomer in the presence of (hetero)--aromatic aldehydes. The racemization method is also suitable for structurally different optically active amino acids.

Processes for preparing �L!- or �D!-homoalanin-4-yl-(methyl) phosphinic

Processes for preparing �L!- or �D!-homoalanin-4-yl-(methyl)phosphinic acid and salts thereof by racemate resolution The title compounds are obtained by racemate resolution of D,L-homoalanin-4-yl (methyl)phosphinic acid via precipitation of one of the diastereomeric salts using chiral bases such as quinine or cinchonine. It is possible to increase the yield of desired enantiomer by transformed racemate resolution when the precipitation of the diastereomeric salt takes place with the racemization of the undesired enantiomer in the presence of (hetero)aromatic aldehydes. The racemization method is also suitable for structurally different optically active amino acids.

Processes for preparing �L!- or �D!-homoalanin-4-yl-(methyl)phosphinic

A large number of customary processes for separating amino acids fails when very polar hydrophilic amino acids with isoelectric points (IEP) which are close to one another are to be fractionated. Mixtures of L-glutamic acid (IEP=3.24) and L-phosphinothricin (IEP=2.6) produced by enzymatic transaminations of the corresponding .alpha.-keto acid have been difficult to separate to date. The invention relates to a process for separating L-phosphinothricin and L-glutamic acid, which comprises carrying out the separation as liquid/liquid extraction with two non-miscible aqueous phases as phase system, where the phase former contained in the phase system is a combination of at least two different water-soluble polymers or of at least one water-soluble salt and one water-soluble polymer, and the extraction is carried out by multistage countercurrent partition on the van Dijck principle.

Process for the extractive separation of L-phosphinothricin and

Process for the preparation of compounds of the formula ##STR1## where R is (C.sub.1 -C.sub.4)alkyl, which comprises reacting a compound of the formula II ##STR2## with an alcoholate of the formula III

Process for the preparation of alkyl methyl-3-carbalkoxyethylphosphinates

Process for the synthesis of alkyl

The present invention relates to a process for the preparation of compounds of the formula I ##STR1## in which R.sup.1 is hydrogen, halogen, alkyl, alkoxy and

Process for the preparation of

The invention relates to a process for the racemization of D-2-N-phenacetylamino-4-methylphosphinobutyric acid ##STR1## which comprises carrying out the racemization in glacial acetic acid and in the presence of acetic anhydride. The invention makes it possible to convert economically a fairly inactive herbicide into the racemic mixture which contains the highly active L form. The latter can be separated off from the racemized mixture by known methods.

Process for the racemization of optically active

The present invention describes a process for the preparation of compounds of the formula I ##STR1## in which R denotes fluorine, chlorine, bromine or (C.sub.1 -C.sub.4)alkyl,

Process for the preparation of ortho-substituted arylcarboximidoesters

A process for the manufacture of 2,6-dichlorobenzoxazole and 2,6-dichlorobenzthiazole by chlorinating K.sup.+ or Na.sup.+ salts of 6-chloro-2-mercaptobenzoxazole or of 6-chloro-2-mercaptobenzthiazole in halogenated hydrocarbons as suspending agents.

Process for the manufacture of 2,6-dichlorobenzoxazole and

The invention provides an improved process for the preparation of N,N'-diformylhydrazine of the formula ##STR1## from the hydrazine hydrate and formamide, which comprises operating in two temperature steps and under reduced pressure in order to remove rapidly the ammonia formed from the system. A very pure product is obtained in a yield of above 95%, relative to hydrazine hydrate.

Process for the preparation of N,N'-diformylhydrazine

1,2,4-triazole is obtained by cyclization of N,N'-diformylhydrazine with ammonia in the presence of formamide. The amount of ammonia required is either formed in situ from thermally decomposable ammonium salts, or supplied by feeding in gaseous ammonia. Simultaneously, the water of reaction is constantly distilled off from the system.

Process for the preparation of 1,2,4-triazole

The amide nitrogen of 9,9-dimethyl-2-oxa-4-oxo-3,8-diazaspiro-(4,5)-decane reacts with isocyanates or diisocyanates to give novel urea derivatives which can be used as light stabilizers for plastic materials.

Urea derivatives, process for their manufacture and their use as light

The invention provides novel 4-carbamoyl derivatives of 1-oxa-3-oxo-4,8-diaza-spiro-[4,5]-decanes and their preparation from 1 oxa-3-oxo-4,8-diaza-spiro-[4,5]-decanes and isocyanates. The products are suitable light stabilizers for thermoplastics.

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Frankfurt am Main, Germany

Harald Knorr