1-Aryl-1,3,5-triazine-4-thione-2,6-diones, production thereof and use thereof as herbicides

A 1-aryl-4-thiotriazine of the formula I

• where the variables have the following meanings:
• R1 is methyl;
• R2 is methyl;
• R3 is hydrogen or halogen;
• R4 is cyano or halogen;
• Y is the methine group;
• R5 is C1-C6-alkoxy, C1-C6-alkylthio, C3-C6-cycloalkoxy, C3-C6-cycloalkylthio, C2-C6-alkenyloxy, C2-C6-alkenylthio, C2-C6-alkynyloxy or C2-C6-alkynylthio, optionally substituted by one of the following substituents:
• halogen, cyano, —CO—R8, —CO—OR8 or —CO—N(R8)—R9, —CO—R11, —C(R11)(OR13)(OR14), —C(R11)═C(R15)—CO—R16, —CH(R11)—CH(R15)—CO—R16, —CO—OR20, —C(R10)═N—OR7, —N(R21)—R22 or —CO—N(R21)—R22;
• R6 is hydrogen, halogen, C1-C6-alkyl, C3-C6-alkenyl, C3-C6-alkynyl, C1-C6-alkoxy, C3-C6-alkenyloxy, C3-C6-alkynyloxy, C3-C6-cycloalkyl or C3-C6-cycloalkoxy, optionally any of the last-mentioned 8 radicals, being substituted by one to three substituents, in each case selected from the group consisting of halogen, C1-C6-alkoxy and —CO—OR8′;
• R7 is hydrogen, C1-C6-alkyl, C1-C6-haloalkyl, C3-C6-cycloalkyl, C3-C6-alkenyl, C3-C6-alkynyl, (C1-C6-alkoxy)carbonyl-C1-C6-alkyl or benzyl;
• R8, R8′ independently of one another are hydrogen, C1-C6-alkyl, C3-C6-cycloalkyl, C3-C6-cycloalkyl-C1-C4-alkyl, C3-C6-alkenyl, C3-C6-alkynyl, C1-C6-alkoxy-C1-C6-alkyl, (C1-C6-alkoxy)carbonyl-C1-C6-alkyl, (C3-C6-alkenyloxy)carbonyl-C1-C6-alkyl, phenyl or phenyl-C1-C6-alkyl, it being possible for the phenyl group and the phenyl ring of the phenyl alkyl group to be unsubstituted or to have attached to them one to three radicals, in each case selected from the group consisting of halogen, nitro, cyano, C1-C6-alkyl, C1-C6-haloalkyl, C1-C6-alkoxy and (C1-C6-alkyl)carbonyl;
• R9 is hydrogen or C1-C6-alkyl;
• R10 is hydrogen, C1-C6-alkyl or C1-C6-alkoxy, it being possible for the 2 last-mentioned radicals to have attached to them one of the following substituents:
• C1-C6-alkoxy, (C1-C6-alkoxy)carbonyl or phenoxycarbonyl;
• R11 is hydrogen, C1-C6-alkyl or C1-C6-haloalkyl;
• R13, R14 independently of one another are C1-C6-alkyl or together are a saturated 2- to 4-membered carbon chain which can have attached to it a C1-C6-alkyl radical;
• R15 is hydrogen, cyano, halogen or C1-C6-alkyl;
• R16 is O—R23 or —N(R21)R22;
• R20, R23 independently of one another are hydrogen, C1-C6-alkyl, C1-C6-haloalkyl, C2-C6-alkenyl or C2-C6-alkynyl, it being possible for any of the last-mentioned 4 groups to be substituted by one or two of the following radicals:
• cyano, halogen, hydroxyl, hydroxycarbonyl, C1-C6-alkoxy, C1-C6-alkylthio, (C1-C6-alkyl)carbonyl, (C1-C6-alkoxy)carbonyl, (C1-C6-alkyl)carbonyloxy, (C3-C6-alkenyloxy)carbonyl, (C3-C6-alkynyloxy)carbonyl or phenyl or phenyl-C1-C6-alkyl, where the phenyl rings can be unsubstituted or, in turn, can have attached to them one to three substituents, in each case selected from the group consisting of cyano, nitro, halogen, C1-C6-alkyl, C1-C6-haloalkyl, C1-C6-alkoxy and (C1-C6-alkoxy)carbonyl;
• R21, R22 independently of one another are hydrogen, C1-C6-alkyl, C3-C6-alkenyl, C2-C6-alkynyl, C3-C6-cycloalkyl, C1-C6-haloalkyl, C1-C6-alkoxy-C1-C6-alkyl, (C1-C6-alkyl)carbonyl, (C1-C6-alkoxy)carbonyl, (C1-C6-alkoxy)carbonyl-C1-C6-alkyl or C1-C6-alkylsulfonyl,
• or R21 and R22 together with the joint nitrogen atom, form a saturated or unsaturated 4- to 7-membered aza heterocycle which optionally contains one of the following members, in addition to carbon ring members:
• —O—, —S—, —N═, —NH— or —N(C1-C6-alkyl)—;
• or an agriculturally useful salt or enol ether of a compound I.