Trifluoroacetic acid → HCID 67684386, compound

Participants

Reaction Steps

To a solution of tert-butyl[2-(2-hydroxy-3-methylpentyl)-4-methoxyphenyl]carbamate (2.65 g) in dichloromethane (25 mL) was added trifluoroacetic acid (5 mL) under ice-cooling. This mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure. To the residue were added ethyl acetate and saturated aqueous sodium hydrogen carbonate solution to separate the organic layer. The organic layer was washed with water and saturated brine successively, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. Under an argon atmosphere, the residue was dissolved in N,N-dimethylformamide (30 mL), and then 2-bromomesitylene (1.50 mL), tetrakis(triphenylphosphine) palladium(0) (472 mg), and potassium carbonate (2.25 g) were added thereto. The mixture was stirred overnight at 150° C. The reaction mixture was cooled to room temperature, and then water was added thereto, followed by extraction with ethyl acetate. The organic layer was washed with water and saturated brine successively, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting solvent: ethyl acetate-hexane) to obtain the title compound (1.46 g). 1H-NMR (CDCl3) δ ppm: 0.91 (3H, t, J=7.4 Hz), 1.32 (3H, d, J=7.0 Hz), 1.55-1.80 (2H, m), 2.75-2.90 (1H, m), 3.84 (3H, s), 6.15-6.20 (1H, m), 6.77 (1H, dd, J=2.4, 8.8 Hz), 7.02 (1H, d, J=2.4 Hz), 7.19 (1H, d, J=8.8 Hz), 7.77 (1H, br s).

Provenance & Evidence