Trifluoroacetic acid → HCID 17842376, compound
Reaction equation
FC(F)(F)C(O)=O.C(O[C:13]([N:15]1[CH2:20][CH2:19][C:18]2[N:21]=[C:22]([C:24]([O:26][CH3:27])=[O:25])[O:23][C:17]=2[CH2:16]1)=O)(C)(C)C>ClCCl>[CH3:27][O:26][C:24]([C:22]1[O:23][C:17]2[CH2:16][N:15]([CH3:13])[CH2:20][CH2:19][C:18]=2[N:21]=1)=[O:25]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Trifluoroacetic acid (15 ml) was added to a solution of 5-(tert-butoxycarbonyl)-2-methoxycarbonyl-4,5,6,7-tetrahydrooxazolo[5,4-c]pyridine (500 mg) in dichloromethane (15 ml) at room temperature, and the mixture was stirred for 10 minutes. The reaction mixture was concentrated under reduced pressure, and dichloromethane (20 ml), triethylamine (0.495 ml), acetic acid (205 ml), formalin (0.230 ml) and sodium triacetoxyborohydride (570 mg) were added to the resultant residue at room temperature. After stirring for 15 minutes, dichloromethane (20 ml) and a saturated aqueous solution (50 ml) of sodium hydrogencarbonate were added to separate an organic layer. The water layer was extracted with dichloromethane (3×20 ml). After the resultant organic layers were combined and dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure. The residue was purified by column chromatography on silica gel (chloroform:methanol=20:1→10:1) to obtain the title compound (257 mg) as a colorless oil.