Hydrochloric Acid → HCID 131730383, compound

Participants

Reaction Conditions

Reaction Steps

Trans-methyl 4-(3-ethoxy-3-oxopropanoyl)-2-(4-fluorophenyl)piperidine-1-carboxylate (1.26 g, 3.59 mmol) (from example 25, step 1) was dissolved in MeOH (50 mL) and cooled to −40° C. under nitrogen. Sodium hydroxide (0.143 g, 3.59 mmol) dissolved in water (5.00 mL) was added during 5 min and the colourless solution continued to stir at −40° C. for 20 min. Hydroxylamine (50% by weight in water, 0.220 mL, 3.59 mmol) was added during 8 min. The resulting solution was stirred at −40° C. for 3 h 20 min. The mixture was transferred into a prewarmed (80° C.) solution of 6 M hydrogen chloride (17.93 mL, 107.58 mmol) and the mixture continued to stir at 80° C. for 20 min. The solvent was evaporated and DCM/water added. The phases were separated and the organic phase passed through a phase separator and evaporated to yield trans-methyl 2-(4-fluorophenyl)-4-(3-oxo-2,3-dihydroisoxazol-5-yl)piperidine-1-carboxylate (1.1 g, 95%) as a brown solid, 1.1 g. MS m/z 321 (M+H)+.

Provenance & Evidence