Triethylamine → (R)-3-(2-(Methoxymethyl)-7-methyl-2H-indazol-5-yl)-1-oxopropan-2-yl 4-(2-oxo-1,2-dihydroquinolin-3-yl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

1-Hydroxy-3-(2-(methoxymethyl)-7-methyl-2H-indazol-5-yl)propan-2-yl 4-(2-oxo-1,2-dihydroquinolin-3-yl)piperidine-1-carboxylate (0.65 g, 1.29 mmol) was dissolved in anhydrous dimethyl sulfoxide (5.0 mL). Triethylamine (0.54 mL, 3.87 mmol) was added and the reaction mixture cooled to ca. 5° C. using an ice bath. A solution of sulfur trioxide pyridine complex (0.62 g, 3.87 mmol) in dimethyl sulfoxide (4.0 mL) was added in one portion. After 1 min, the ice bath was removed and the reaction mixture stirred at room temperature for 20 min. The reaction mixture was poured into an ice slurry and extracted with ethyl acetate (3×). The combined organic extracts were washed with 10% citric acid (2×), water (2×), 5% sodium bicarbonate (2×), brine (2×), dried over sodium sulfate, and concentrated. Column chromatography afforded 0.55 g (85%). 1H-NMR (DMSO. d6, 500 MHz) δ 1.90 (s, 3H), 2.48 (s, 3H), 2.51 (m, 2H), 2.71-2.95 (m, 4H), 4.51 (m, 1H), 4.72-4.84 (m, 1H), 6.31-6.46 (m, 1H), 6.91 (d, J=4.0, 1H), 8.36 (s, 1H), 11.74 (s, 1H). Mass spec.: 503.3 (MH)+.

Provenance & Evidence