2-(3,4-dichlorophenyl)-4,4-dimethylsemicarbazide and its alkyl - derivs - selective herbicides

摘要

Insecticidal semicarbazide are of formula (I):- where R3 = H or (1-4C) alkyl (and pref. H or Me). (R3=H) are prepd. by reacting the benzaldehyde deriv. with 2,4-dinitrophenylhydrazine. This can then by alkylated, via the N-trifluoroacetyl deriv. to give (I) (R3=alkyl).