n - (alkoxyalkyl) - 2.4 - dialkyltetrahydrothien - 3 - ylideniminderivater and procedure for the production of n - (2,4 - dialkylthien - 3 - yl) - n - (alkoxy alkyl) chloracetamidderivater using n - (alkoxyalkyl) - 2.4 - dialkyltetrahydrothien - 3 - ylideniminderivaterne

摘要

Compounds of the formula I IMAGE where R denotes C1-4-alkoxy-C2-4-alkyl, where the C1-4- alkoxy group having at least two carbon atoms is separate from the N atom to which R is bonded, each of the symbols R2 and R4, independently of each other, denote CH3 or C2H5, and R5 denotes H or CH3, are prepared by reacting tetrahydrothiophen-3-ones of the formula IV IMAGE with an amine of the formula V H2N-R V Compounds of the formula IV are obtained by cyclizing a compound of the formula VI HO-CO-CH(R2)-S-CH(R5)-CH(R4)COOH VI which, for its part, can be obtained by adding a compound of the formula VII HO-CO-CH(R2)-SH VII to a compound of the formula VIII R5-CH=C(R4)-COOH VIII Compounds I can be dehydrogenated to from compounds II IMAGE which are known intermediates for preparing known herbicides of the formula III IMAGE by means of N-chloroacetylation.