Dsm Fine Chemicals Austria Nfg Gmbh & Co. Kg

Syngenta Crop Protection, Inc.

Syngenta Participations Ag

Sylvia Krich

Gerhard Steinbauer

Wolfram Hendel

Christian Burger

Johann Altreiter

Ferdinand Heu

Bernhard Holub

Alexander Rieder

Birgit Zw&ouml;lfer

Birgit Zwölfer

Process for the preparation of substituted thiazolines of the formula (I)in which Ar is a phenyl, naphthyl, thienyl, pyridyl or quinolinyl radical which can optionally be substituted by one or more substituents from the group consisting of halogen, OH, benzyloxy, C-C-alkyl, C-C-alkoxy, COORwhere Ris H or C-C-alkyl,by coupling of (S)-&#x3b1;-methylcysteine hydrochloride of the formula (II)with a nitrile of the formula (III)Ar&#x2014;CNin which Ar is as defined above, or a corresponding C-C-alkyl imidate, in which (S)-&#x3b1;-methylcysteine hydrochloride of the formula (II) is reacted in a suitable solvent with a nitrile of the formula (III) or a corresponding C-C-alkyl imidate in the presence of a tertiary base at a pH of 6.5 to 10 at 50&#xb0; C. up to the reflux temperature to give the corresponding thiazoline of the formula (I), and processes for the preparation of (S)-&#x3b1;-methylcysteine hydrochloride and its use for the preparation of thiazolines of the formula (I).

Process for the preparation of substituted thiazolines and their intermediates

The invention relates to a method for producing 2-chloro-5-chloromethyl-1,3-thiazol from compounds of formula (I), wherein X means Cl, &mdash;OR, &mdash;SR or NR , R being H or a suitable protective group; Y means H or Cl and Z means Cl or O, the compounds of formula (I) having at most one double bond between C* and C&Prime; or between C&Prime; and Z, on the condition that the bond between C&Prime; and Z is a double bond when Z is the same as O and a single bond when Z is the same as Cl; with the following intermediate stage: A ) reacting 2,3-dichloropropanal with rhodanide and acetalising to 3-chloro-1,1-dialkoxy-2-isothiocyanato-propane or a ) reacting 2,3-dichloropropanal with thiourea to form a mixture of the hydrochlorides of the compounds N-&lsqb;&lsqb;5-(2-aminothiazol)yl&rsqb;methyl&rsqb;thiourea and &lsqb;5-(2-aminothiazol)yl&rsqb;methylthioformamidine and splitting to obtain the corresponding thiol or amine or b) reacting a compound of formula (I) wherein X means OR, SR or NR , Y means clorine and Z means oxygen with thiourea to produce the compound of formula (V), or c) reacting a compound of formula (I), wherein X means OR, SR or NR , Y means chlorine and Z means oxygen with ammoniumdithiocarbamate or ammoniumthiocarbamate, to produce the compound (VIa) or (VIb); d) converting 1,2,3-trichloropropane to the corresponding thiazolidine and then dehydrogenating or e) converting 1,3-dichloro-prop-1-ene to the corresponding epoxide and then reacting said epoxide with thiourea (e ) or ammoniumdithiocarbamate or ammoniumthiocarbamate (e ).

Method for producing 2-chloro-5-chloromethyl-1,3-thiazol

A process for the preparation of 2-chloro-5-chloromethyl-1,3-thiazole, in which allyl isothiocyanate of formula CH &boxH;CH&mdash;CH &mdash;NCS is reacted at from &minus;40&deg; C. to &plus;30&deg; C., in a solvent that is inert under the reaction conditions, with from 1 to 2 mol of a chlorinating agent per mol of allyl isothiocyanate; to the reaction mixture so obtained there is added, at a reaction temperature of from 0&deg; C. to the boiling temperature of the solvent used, from 1 to 5 mol of oxidising agent per mol of allyl isothiocyanate, and then 2-chloro-5-chloromethyl-1,3-thiazole is isolated from the reaction mixture and is optionally converted by crystallisation into high-purity 2-chloro-5-chloromethyl-1,3-thiazole.

Method for producing 2-chloro-5-chloromethyl-1,3-thiazole

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Altenberg, Austria

Sylvia Krich