Hydrochloric Acid → HCID 118020716, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of methoxymethyltriphenyl phosphonium chloride (5.4 g, 15.7 mmol) in THF (50 mL), n-butyl lithium (a 2.6 mol/L hexane solution, 6.3 mL, 16.5 mmol) was added under cooling at −78° C., and the resulting mixture was stirred for 30 minutes. The reaction mixture was heated to 0° C., a solution of 1-(5-fluoropyridin-2-yl)-1H-pyrazole-3-carbaldehyde obtained in Reference Example 29 (1.5 g, 7.9 mmol) and hexamethylphosphoric triamide (0.5 mL) in THF (50 mL) was added thereto, the resulting mixture was stirred for 3 hours, then heated to room temperature and stirred for 15 hours. To the reaction mixture, EtOAc and a saturated aqueous solution of sodium chloride were added under cooling in an ice bath and stirred to separate the organic layer. The organic layer was dried over MgSO4, then the drying agent was filtered off, and then the solvent was distilled off under reduced pressure to obtain a brown oil. To the obtained brown oil, an aqueous solution of hydrochloric acid (1.2 mol/L, 10 mL) was added, and the resulting mixture was heated to reflux and stirred for 2 hours. The reaction mixture was allowed to cool at room temperature, then water was added thereto, followed by extraction with EtOAc. The organic layer was washed with a saturated aqueous solution of sodium chloride, dried over MgSO4, then the drying agent was filtered off, and then the solvent was distilled off under reduced pressure. The obtained residue was purified by column chromatography (HIP-Sil 25 g, hexane/EtOAc=80/20 to 20/80) to obtain the title compound (1.0 g) (light yellow oil).

Provenance & Evidence