Sodium Hydroxide → HCID 178488035, compound

Participants

Reaction Conditions

Reaction Steps

2-(chloromethyl)-3,5-dimethyl-4-methoxy pyridine hydrochloride (70 g) and 2-mercapto-5-methoxybenzimidazole (57.4 g) were taken in methanol (245 mL) at 25° C. and sodium hydroxide (31.5 g) solution in water was added. The reaction mixture was stirred for 45 min and quenched in water (490 mL). The reaction mixture was acidified with 10% glacial acetic acid (75 mL) and extracted with toluene (350 mL). The toluene extract was washed with water and partially distilled for azeotropic removal of water. The reaction mixture was cooled to 25° C. and water (0.68 mL), D-(−)-Diethyl tartrate (38.2 g), Titanium isopropoxide (28.5 g) were added. The reaction mixture was heated to 50° C. for 1 hour and cooled to 0° C. Diisopropylethylamine (12 g) and cumene hydroperoxide (80%) (60 g) were added and stirred for 20 min at 15° C. The reaction mixture was stirred for 8 hours at 15° C. Sodium thiosulfate (14.4 g) aqueous solution and aqueous sodium hydroxide (60 g) solution were added to the reaction mixture. The separated aqueous layer was treated with methylene dichloride (500 mL) and acidified with glacial acetic acid to adjust the pH of 6.5. The separated organic layer was distilled under vacuum to obtain residue. Methanol (250 mL) was added to the residue and magnesium methoxide solution (3.3 g) in methanol:methylene dichloride (100:8 mL) was added at 25° C. The reaction mixture was stirred for 9 hours and catalytic amount of water (1.0 mL) was added. The reaction mixture was filtered and washed with methanol (70 mL). The filtrate was treated with charcoal and distilled under vacuum to obtain residue. Acetone (50 mL) was added to the residue and stirred for 2 hours at 25° C. The slurry was filtered and washed with acetone/methanol (90:10 mL) and dried to obtain wet-cake (95 g) of esomeprazole magnesium. The wet-cake was dissolved in methanol (350 mL) and charcoalized. The reaction mixture was filtered and methanol was partially distilled from filtrate to obtain residue with 3 times of methanol. Acetone (800 mL) was added to the residue at 25° C. and stirred for 2 hours. The reaction mixture was filtered and wet-cake was washed with acetone/methanol (90:10 mL). The product was dried in tray drier followed by vacuum drying till residual solvents are within the ICH limits to obtain 77 g esomeprazole magnesium dihydrate. Water content 6.15% (by KF), X-ray powder diffraction (FIG. 1) and Differential scanning calorimetry (FIG. 2).

Provenance & Evidence