Isothiazolecarboxamides and their use as microbicides

An isothiazolecarboxamide of the formula

• wherein
• X represents fluoro, chloro, bromo, methyl, ethyl or trifluoromethyl,
• Y represents a hydrogen atom, fluoro, chloro, bromo, cyano, methoxycarbonyl or ethoxycarbonyl,
• R1 represents a hydrogen atom,
• R2 represents a hydrogen atom or methyl,
• R4 represents methyl or ethyl,
• R3 represents a hydrogen atom, C1-12 alkyl, C3-6 cycloalkyl, C2-6 alkenyl which may be substituted with phenyl, or
• R3 represents C5-6 cycloalkenyl, C7 bicycloalkenyl, C1-2 haloalkyl, or
• R3 represents C1-4 alkyl, which is substituted with 1 or 2 substituents selected from the group consisting of hydroxy, C1-4 alkoxy, mercapto, C1-4 alkylthio, C1-4 alkylsulfinyl, C1-4 alkylsulfonyl, phenyl and a 5-membered heterocyclic ring having 1-3 nitrogen atoms which may be benzo-condensed, or
• R3 represents phenyl, which may be substituted with 1 to 4 groups selected from the group consisting of C1-4 alkyl, halogen, C1-4 haloalkyl, C1-4 haloalkoxy, nitro, cyano, C1-4 alkoxy, benzyloxy, phenoxy, C1-4 alkylenedioxy, C1-4 alkylthio, di-C1-4 alkyl-amino and phenyl, or
• R3 represents naphtyl, which may be substituted with methoxy, or
• R3 represents a 5- or 6-membered heterocyclic group, which has 1 to 3 heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, which heterocyclic groups may be benzo-condensed and may be substituted with 1 to 3 substituents selected from the group consisting of C1-4 alkyl, halogen C1-4 alkoxy, C1-4 alkylthio and nitro,
• or
• R2 and R3, together with the carbon atom to which they are bonded, form a C5-6 cycloalkyl, which may be substituted with 1 or 2 methyl groups, or
• R2 and R3, together with the carbon atom to which they are bonded, form a 5- or 6-membered heterocyclic ring, which comprises one nitrogen atom and which may be substituted with 1 or 2 methyl groups, or
• R2 and R3, together with the carbon atom to which they are bonded, form a group of the formula
• C═CH—R5, in which
• R5 represents a hydrogen atom, methyl or ethyl,
• or
• R3 and R4, together with the carbon atom and the carboxyl group to which they are bonded, form a 5- or 6-membered heterocyclic ring having one ring-constituting oxygen atom and being substituted with one oxo group,
• with the proviso, however, that
• R3 does not represent isopropyl,
• if
• X and Y represent chloro, and
• R2 represents a hydrogen atom.