Acetic Acid → HCID 69479566, compound

Participants

Reaction Steps

(S)-2-[4-(4-Trifluoromethoxyphenyl)aminopiperidin-1-yl]methyl-2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole prepared in Example 282 (400 mg, 0.90 mmol) was dissolved in methanol (10 ml). To the solution, a 37% formaldehyde solution (0.13 ml, 4.52 mmol), sodium cyanotrihydroborate (170 mg, 2.71 mmol) and acetic acid (0.17 ml, 2.71 mmol) were added followed by stirring at room temperature for 30 minutes. The reaction mixture was poured into a saturated sodium hydrogencarbonate solution and extracted with methylene chloride. The organic phase was dried over magnesium sulfate and then filtered. The resulting filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (methylene chloride/methanol=100/1) and recrystallized from methylene chloride-diisopropyl ether to afford (S)-N-[1-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperidin-4-yl]-N-methyl-4-trifluoromethoxyaniline (309 mg, yield 78%) as a light yellow crystals.

Provenance & Evidence