NEW MATERIAL:A compound shown by formula I [A is OH, OH, methoxy, ethoxy or halogen; X is H, methyl, ethyl, phenyl or p-chlorophenyl; when Y is 2-fluoroethyl, Z is 1 to 4C (halo)alkyl, 2 to 4C (halo)alkenyl, (halo-substituted) phenyl, N,N-dimethylsulfamoyl or N,N-dimethylcarbamoyl and when Z is 2- fluoroethyl, Y is H, 1 to 4C (halo)alkyl (except 2-fluoroethyl), 2 to 4C (halo) alkenyl or alkoxycarbonylmethyl; (n) is 1 or 2].

USE: An organic phosphorous agent and a controller against harmful organism and having high effects on harmful organisms with resistance to synthetic pyrethroid agents.

PREPARATION: For example, a compound shown by formula II is reacted with 1-bromo-2-fluoroethane in the presence of a base to give a compound shown by formula I wherein Y and Z are simultaneously 2-fluoroethyl.