Sodium Carbonate → 1-[(Diethoxyphosphorothioyl)oxy]-1H-pyrazole

Participants

Reaction Steps

112 part of diethyl thiophosphate chloride were added to 55 parts of 1-hydroxypyrazole and 50 parts of sodium carbonate in 600 parts of acetonitrile at 25° C., with stirring. Stirring was continued for another 12 hours. The solid product was filtered off with suction and washed with two portions of 50 parts of acetonitrile. The filtrate was concentrated in a rotary evaporator at from 20° to 40°C. under 20 mbar. The residue as dissolved in 300 parts by weight of methylene chloride, the organic phase was extracted with three portions of 50 parts by weight of saturated aqueous NaHCO3 solution, the methylene chloride solution was dried with magnesium sulfate and the solvent was stripped off in a rotary evaporator at from 20° to 40° C. under 20 mbar to give 127.5 parts by weight (91% of theory) of O-pyrazol-1-yl O,O-diethyl thiophosphate.

Provenance & Evidence