Process for the preparation of certain triaryl pesticide intermediates

A process for preparing triaryl pesticide intermediates of the Formula (I),

• wherein
• R1 represents NO2 or CO2R3,
• R2 represents C1-C6 haloalkoxy, and
• R3 represents C1-C6 alkyl
• which comprises:
• a) contacting a substituted phenyl hydrazine of Formula (II)
• wherein
• R2 is as previously defined,
• X represents Cl or Br, and
• n=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, and
• Y 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.