3-Isoxazolylphenyl compounds Ia and Ib ##STR1## where R is halogen; alkyl; haloalkyl; alkoxy; haloalkoxy; alkenyl; haloalkenyl; unsubstituted or substituted phenylethenyl; alkynyl; cycloalkyl; aryl; hetaryl; CO.sub.2 R.sup.6 or CONR.sup.7 R.sup.8,R.sup.6 is hydrogen, alkyl, cycloalkyl or benzyl;R.sup.7 and R.sup.8 are each hydrogen, alkyl, cycloalkyl or benzyl or, together with the nitrogen atom to which they are bonded, form a heterocyclic radical;n is 0, 1 or 2;R.sup.1 is halogen or alkyl;R.sup.2 is hydrogen; alkyl; alkenyl; alkynyl or cyano;R.sup.3 and R.sup.4 independently of one another are each unsubstituted or substituted alkyl, alkenyl, cycloalkyl, phenyl, naphthyl, pyridyl or pyrimidinyl; or R.sup.3 and R.sup.4 together form unsubstituted or substituted alkylene;R.sup.5 is hydrogen; unsubstituted or substituted alkyl or one of the groups stated for R.sup.3 ;X is CH.sub.2, O, S or NR.sup.9 andR.sup.9 is hydrogen, alkyl, cycloalkyl, alkenyl, alkynyl or unsubstituted or substituted benzyl, processes for their preparation, agents containing them and the use thereof.