The invention relates to a method for producing an organic compound of formula (I) and optionally its E/Z-isomers, E/Z-isomer mixtures and/or tautomers, each in free or salt form, R1 representing hydrogen or C1-C4 alkyl, R2 representing hydrogen, C1-C6 alkyl, C3-C6 cycloalkyl or a radical —CH2B, Het representing an unsubstituted or substituted heterocyclic radical and B representing phenyl, 3-pyridyl or thiazolyl, these being optionally substituted. The invention is characterized in that a compound of formula (IIa) Q—A—Q, wherein A represents a direct bond or an organic radical, or of formula (IIb), wherein U represents an organic radical, Q representing (1) in the compounds (IIa) and (IIb) and R1, R2 and Het having the meaning given above for formula (I), and optionally their E/Z-isomers, E/Z-isomer mixtures and/or tautomers, each in free or salt form are hydrolyzed. The invention also relates to a method for producing compounds of formulae (IIa), (IIb), (IIIa) and (IIIb), and to a method for combating pests with compounds of formulae (IIa) and (IIb).