PROCESS FOR THE PREPARATION OF CERTAIN TRIARYL PESTICIDE INTERMEDIATES

摘要

Certain intermediates useful in the preparation of triaryl pesticides are prepared from a substituted phenyl hydrazine and a substituted benzaldehyde by a cyclization process.

主权项

1. A process for preparing triaryl pesticide intermediates of the Formula (I),
wherein R1 represents NO2 or CO2R3,R2 represents C1-C6 haloalkoxy, andR3 represents C1-C6 alkylwhich comprises:
a) contacting a substituted phenyl hydrazine of Formula (II) wherein R2 is as previously defined,X represents Cl or Br, andn=0, 1 or 2,with a substituted benzaldehyde of Formula (III)
wherein R1 is as previously defined,in an inert organic solvent to provide a hydrazone of Formula (IV)
wherein R1 and R2 are as previously defined; b) chlorinating or brominating the hydrazone of Formula (IV) with a chlorinating or brominating agent in the presence of a sulfide in an inert organic solvent to provide a halohydrazone of Formula (V) wherein R1 and R2 are as previously defined, andY represents Cl or Br; and c) contacting the halohydrazone of Formula (V) with an amine of formula
R4CH2NH2 wherein
R4 represents H, Si(CH3)3 or CH(C6H5)2 in the presence of an organic base followed by oxidizing with an oxidizing agent.