Procedure for obtaining derivatives o- (o-ethyl-s-alquilfosforil) -O- (carbamoyl) -brenzcatequina pesticidal effect.

DERIVATIVES O - (O - ETHYL - S - ALQUILFOSFORIL) - O (carbamoyl) - catechol of the general formula (I) wherein the substituents have the following meanings: R1, C1-C4-alkyl, R2, hydrogen, C1 C4-alkyl or C1-C4-alkoxy, R3, hydrogen or C1-C4 alkyl YX, oxygen or sulfur, their manufacture and their use for the Parasite Control.