6-(2-chloro-4-alkoxy-phenyl)-triazolopyrimidines, method for the production thereof and its utilization for controlling fungi and agents contained therein

6-(2-Halo-4-alkoxyphenyl)triazolopyrimidines of the formula I in which the substituents are as defined below: R1 is alkyl, haloalkyl, cycloalkyl, halocycloalkyl, alkenyl, haloalkenyl, cycloalkenyl, halocycloalkenyl, alkynyl, haloalkynyl or phenyl, naphthyl, or a five- or six-membered saturated, partially unsaturated or aromatic heterocycle which contains one to four heteroatoms from the group consisting of O, N and S, R2 is hydrogen or one of the groups mentioned under R1, R1 and R2 together with the nitrogen atom to which they are attached may also form a five- or six-membered heterocyclyl or heteroaryl which is attached via N and may contain one to three further heteroatoms from the group consisting of O, N and S as ring members; R3 is alkyl, haloalkyl, alkenyl, haloalkenyl, alkynyl, haloalkynyl, phenylalkyl, mono- or dialkoxyalkyl; R1, R2 and/or R3 may be substituted as mentioned in the description; L is hydrogen, fluorine or chlorine; X is cyano, alkyl, alkoxy, alkenyloxy, haloalkoxy or haloalkenyloxy; processes for preparing these compounds, compositions comprising them and their use for controlling phytopathogenic harmful fungi.