Sodium Carbonate → HCID 21471614, compound

Participants

Reaction Steps

A mixture of 4.5 g N-t-butyloxycarbonyl-4-piperidone, 4.7 g of 4-(5-methyl-2-oxo-1-benzimidazolinyl)piperidine, 65 mL of 1,2-dichloroethane, 1.3 mL of glacial acetic acid and 6.4 g of sodium triacetoxyborohydride was stirred at room temperature for 48 h. The reaction mixture was poured into 500 mL chloroform and 500 mL saturated aqueous Na2CO3 and the layers separated. The aqueous layer was extracted with 2×250 mL of chloroform and the combined organic layers dried over MgSO4 and concentrated under reduced pressure. Recrystallization of the crude product from 50 mL of ethyl acetate gave in two crops 6.18 g of pure 5-methyl-1,3-dihydro-1-{1-[1-(t-butyloxycarbonyl)piperidin-4-yl]piperidin-4-yl}-2H-benzimidazol-2-one as a white solid: mp 210°-211° C.

Provenance & Evidence