Sodium Hydroxide → Fenoxanil

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of sodium bicarbonate (1.446 kg; 17.2 mol) in water at -3° to 3° C. is treated with a toluene solution of 2-amino-2,3-dimethylbutyronitrile (1.51 kg, 13.46 mol) over a 15 minute period, then treated sequentially with a toluene solution of (R)-2-(2,4-dichlorophenoxy)propionyl chloride (3.346 kg, 13.2 mol) over a 1.5 hour period at ice bath temperatures, stirred for 0.5 hours, treated with 50% NaOH (0.396 kg), heated to 55° C. and stirred for 0.5 hours. The resultant mixture is separated. The organic phase is washed with 5% NaOH and distilled at temperatures up to 80° C. at 10 mm Hg to remove the toluene. The pot residue is crystallized in isopropanol/water to afford the title product as a white solid, 4.131 kg (94.8% yield), characterized by HPLC analysis. The product is 99.7% pure. The isomer ratio is: 94.8% RR, RS and 5.2% SS, SR.

Provenance & Evidence