Compounds of the formula (I) and also process for preparing them ##STR1## where substituents X.sup.1, X.sup.2, Y and Z are defined as follows: X.sup.1 is H or F X.sup.2 is H or F Y is CI, Br, or I Z is CHO or COOH or CN n is 0 or 1 and also their use as starting material for preparing agrochemicals, electronics materials and pharmaceuticals.