Hydrochloric Acid → Cyantraniliprole

Participants

Reaction Conditions

Reaction Steps

To a mixture of 3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazole-5-carboxylic acid (see PCT Patent Publication WO 2003/015519 for a method of preparation) (97.6% purity, 3.10 g, 0.01 mol) and 2-amino-5-cyano-N,3-dimethylbenzamide (i.e. prepared by the method of Example 2) (2.00 g, 0.01 mol) in acetonitrile (24 mL) was added 3-picoline (2.92 mL, 0.03 mol). The mixture was cooled to between −5 and −10° C., and then methanesulfonyl chloride (1.08 mL, 0.014 mol) was added dropwise. The mixture was stirred for 5 minutes at −10 to −5° C., and then for 3 h at 0 to 5° C. After 3 h water (11 mL) was added dropwise to the mixture while maintaining the temperature at 0 to 5° C. After 15 minutes, concentrated hydrochloric acid (1.0 mL) was added and the mixture was stirred for 1 h at 0 to 5° C. The mixture was filtered and the solids collected were washed with acetonitrile-water (2:1 mixture, 2×2 mL) and acetonitrile (2×2 mL), and then dried under nitrogen to afford the title compound (4.78 g, 95.8% corrected yield based on assay of 95%) as an off-white solid melting at 206-208° C.

Provenance & Evidence