Dichloromethane → HCID 178493213, compound

Participants

Reaction Conditions

Reaction Steps

2-Chloromethyl-3,4-dimethoxy pyridine hydrochloride (50 gms), 2-mercapto-5-difluoromethoxy benzimidazole (50 gms) and Tetra butyl ammonium bromide (2 gms) were added under stirring to dichloromethane (300 ml) followed by solution of sodium hydroxide (37.5 gms) in 120 ml water. The contents were then stirred at 25-30° C. for about 12 hours. After reaction completion, the dichloromethane layer was separated, then the aqueous layer was extracted with dichloromethane (60 ml) twice. The organic layers were combined together, water washed and distilled to about 250 ml and cooled to 0° C. 3.5% aqueous sodium hypochlorite solution (464 g) having a sodium hydroxide content of 2.2% was added to the reaction mass, which was maintained at 5-8° C. for about 6 hours. After completion of the reaction; the reaction mass was further cooled to 0 to 5° C. The resulting solid was then filtered and washed with cold acetone (about 100 ml) and dried under vacuum at 35-40° C. to give pantoprazole sodium (75 gms, 83%) of purity greater than 99.5%.

Provenance & Evidence