Hydrochloric Acid → HCID 131730394, compound

Participants

Reaction Conditions

Reaction Steps

Trans-methyl 2-(4-tert-butylphenyl)-4-(3-ethoxy-3-oxopropanoyl)piperidine-1-carboxylate (1.09 g, 2.80 mmol) was dissolved in MeOH (10 mL) and cooled to −40° C. Sodium hydroxide (0.112 g, 2.80 mmol) dissolved in water (1.2 mL) was added over 1 min and the resulting solution was stirred at −40° C. for 20 min. Then, hydroxylamine (50% in water, 0.178 mL, 2.91 mmol) was added over 1 min and stirring continued at −40° C. for 3 h. The reaction mixture was then transferred into a prewarmed (80° C.) solution of 6M hydrogen chloride (30 mL, 180.00 mmol) and the mixture was continued to be stirred at 80° C. for 1 h. Then cooled to room temperature. Methanol was evaporated, then water was added. Extracted three times with DCM. Combined organic layers dried over MgSO4 and evaporated. Crude trans-methyl 2-(4-tert-butylphenyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (910 mg, 90%) was isolated as off-white foam. 1H NMR (400 MHz, cdcl3) δ 1.32 (s, 9H), 1.46-2.23 (m, 3H), 2.46-3.05 (m, 3H), 3.74 (s, 3H), 3.98-4.43 (m, 1H), 5.48-5.72 (m, 2H), 7.10-7.22 (m, 2H), 7.35-7.45 (m, 2H). MS m/z 359 (M+H)+

Provenance & Evidence