反应详情

温度

0 °C

Tri-n-butylphosphine (8.4 mL, 34 mmol) was added dropwise over 5 min to 3-(2-methoxyphenylsulfonyloxy)-5-methylphenol (4.97 g, 16.9 mmol, prepared in the preceding step), 1,3-propanediol (12 mL, 170 mmol) and 1,1′-(azodicarbonyl)dipiperidine (8.54 g, 33.8 mmol) in anhydrous tetrahydrofuran (75 mL) at 0° C. under a nitrogen atmosphere. Dichloromethane (75 mL) was added mid-way through the tri-n-butylphosphine addition to aid stirring. The slurry was stirred at ambient temperature for 1 h, then the mixture was cooled to 0° C. and additional 1,1′-(azodicarbonyl)dipiperidine (4.27 g, 16.9 mmol) and tri-n-butylphosphine (4.2 mL, 16.9 mmol) were added. The reaction was stirred overnight at ambient temperature. Diethyl ether (200 mL) was added and the mixture was filtered. The filtrate was concentrated in vacuo, and the residue was purified by flash column chromatography (25% ethyl acetate in hexane to 60% ethyl acetate in hexane, then 2% acetone in dichloromethane to 7% acetone in dichloromethane in two separate chromatographic separations) to give the title compound (3.79 g, 64%) as a gold oil. 1H-NMR (300 MHz, CDCl3) δ7.82 (dd, 1H, J=7.9, 1.7 Hz), 7.61 (ddd, 1H, J=8.4, 7.5, 1.8 Hz), 7.08 (d, 1H, J=8.4 Hz), 7.01 (ddd, 1H, J=7.9, 7.5, 1 Hz), 6.58 (br s, 1H), 6,51 (br s, 1H), 6.46 (t, 1H, J=2.1 Hz), 4.02 (s, 3H), 4.00 (t, 2H, J=6.0 Hz), 3.81 (dt, 2H, J=5.7, 5.3 Hz), 2.24 (s, 3H), 1.98 (pentet, 2H, J=6.0 Hz), 1.72 (t, 1H, J=5.0 Hz). Mass spectrum (MALDI-TOF, (α-cyano-4-hydroxycinnamic acid matrix) calcd. for C17H20O6S: 375.1 (M+Na). Found: 375.1.

1. stirringThe slurry was stirred at ambient temperature for 1 h
2. stirringThe reaction was stirred overnight at ambient temperature
3. filtrationthe mixture was filtered
4. concentrationThe filtrate was concentrated in vacuo
5. customthe residue was purified by flash column chromatography (25% ethyl acetate in hexane to 60% ethyl acetate in hexane
6. custom2% acetone in dichloromethane to 7% acetone in dichloromethane in two separate chromatographic separations)