Imidazolopyrimidines used as fungicidal active ingredients

An imidazolopyrimidine of formula (I)

• and salts thereof,
• in which
• R1 represents H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, or optionally substituted heterocyclyl;
• or represents an organic radical that contains 3 to 13 carbon atoms and one or more silicon atoms and optionally 1 to 3 identical or different heteroatoms selected from the group consisting of oxygen, nitrogen, and sulphur and which that is unsubstituted or substituted by 1 to 4 identical or different halogens,
• R2 represents an organic radical that contains 3 to 13 carbon atoms and one or more silicon atoms and optionally 1 to 3 identical or different heteroatoms selected from the group consisting of oxygen, nitrogen, and sulphur and which that is unsubstituted or substituted by 1 to 4 identical or different halogens, or
• R1 and R2 together with the nitrogen atom to which they are attached represent an optionally substituted heterocyclic ring that contains one or more silicon atoms and/or is substituted by one or more radials R2,
• R3 represents optionally substituted aryl, optionally substituted heterocyclyl, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted alkynyl, optionally substituted cycloalkyl, optionally substituted aralkyl, halogen, or optionally substituted amino, optionally substituted (C1-C8)-alkoxy, optionally substituted (C1-C8)-alkylthio, optionally substituted (C6-C10)-aryloxy, optionally substituted (C6-C10)-arylthio, optionally substituted heterocyclyloxy, optionally substituted (C6-C10)-aryl-(C1-C4)-alkoxy, optionally substituted (C6-C10)-aryl-(C1-C4)-alkylthio, optionally substituted heterocyclyl-(C1-C4)-alkoxy, or optionally substituted heterocyclyl-(C1-C4)-alkylthio,
• R4 represents H, halogen, optionally halogen-substituted alkyl, or optionally halogen-substituted cycloalkyl,
• R5 represents H, halogen, optionally halogen-substituted alkyl, or optionally halogen-substituted cycloalkyl, and
• X represents halogen, cyano, optionally substituted alkyl, optionally substituted alkoxy, or optionally substituted phenyl.