Disclosed are a method for producing fungicidal triazolopyrimidine compounds, agents containing said compounds, and the use thereof for controlling harmful fungi. Also disclosed are triazolopyrimidines of formula (I), in which the substituents have the following meaning: L1 represents alkyl; L2 represents halogen; L3represents hydrogen or halogen; X represents halogen, cyano, alkyl, alkoxy, or haloalkoxy; R1, R2 represent hydrogen, alkyl, haloalkyl, cycloalkyl, alkenyl, alkadienyl, alkinyl, or cycloalkinyl, phenyl, naphthyl, or a five-unit to ten-unit saturated, partially unsaturated, or aromatic heterocycle containing one to four heteroatoms from the group O, N, or S, R1 and R2 can also form a five-unit or six-unit ring along with the nitrogen atom to which they are linked. Said ring can be interrupted and/or substituted by an atom from the group O, N, and S while R1 and/or R2 can be substituted according to the description. The invention also relates to methods and intermediate products for producing said compounds, agents containing said compounds, and the use thereof for controlling harmful fungi