Sodium borohydride → HCID 18917630, compound

Participants

Reaction Steps

5-Ethyl-3-(4-methoxybenzoyl)-2-(3-hydroxymethyl-5-undecyl-1,2,4-triazol-4-yl)thiophene (4.4 g) obtained in Example 20 was dissolved in ethanol (100 ml). Thereto was added sodium borohydride (0.16 g) with stirring and the mixture was stirred at room temperature for 1 hour. After the ethanol was distilled away, 5% aqueous sodium hydrogencarbonate was added thereto and the liberated oily substance was extracted with ethyl acetate. The extract was washed with water and dried over anhydrous magnesium sulfate. After filtration, the filtrate was concentrated under reduced pressure and toluene (100 ml) was added to the residue. The mixture was refluxed under heating with stirring and sulfuric acid was gradually added dropwise until the reaction ended. After cooling, 5% aqueous sodium hydrogencarbonate was added thereto and the mixture was extracted with ethyl acetate. The extract was washed with water and dried over anhydrous magnesium sulfate. After filtration, the residue was concentrated under reduced pressure and the residue was purified by silica gel column chromatography. The oily substance obtained was crystallized from hexane to give 1.64 g of 2-ethyl-4-(4-methoxyphenyl)-9-undecyl-4H,6H-thieno[2,3-e][1,2,4]triazolo[3,4-c][1,4]oxazepine as white crystals, melting point 91°-93° C.

Provenance & Evidence