Trifluoroacetic acid → HCID 5278893, compound

Participants

Reaction Steps

0.80 g of (R)-2-methyl-2-(4-(4-(N-methyl-N-tert-butoxycarbonylamino)piperidin-1-yl)phenoxymethyl)-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole was dissolved in 2 ml of trifluoroacetic acid and 2 ml of dichloromethane, followed by stirring at room temperature for 15 hours. Thereafter, the reaction solution was concentrated under a reduced pressure, and then, 2 ml of dichloromethane and 2 ml of triethylamine were added thereto. The mixture was stirred at room temperature for 5 minutes, and it was then concentrated under a reduced pressure. The residue was dissolved in 8 ml of dichloroethane, and then, 0.57 g of 2-trifluoromethylbenzaldehyde and 0.70 g of triacetoxy sodium borohydride were added thereto while cooled by ice. The mixture was warmed to room temperature, and the mixture was then stirred for 24 hours. Thereafter, an aqueous solution of potassium carbonate and dichloromethane were added to the reaction solution. The mixture was stirred, and then extracted with dichloromethane. The organic layer was dried over magnesium sulfate, and then filtered. The obtained filtrate was concentrated under a reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane:methanol=9:1). The resultant product was then crystallized from ethyl acetate to obtain 0.47 g (yield: 52.4%) of light yellow powders, (R)-2-methyl-2-(4-(4-(N-methyl-N-(2-trifluoromethylbenzyl)amino)piperidin-1-yl)phenoxymethyl)-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole.

Provenance & Evidence