反应详情

In a 500 ml three-neck flask fitted with a condenser and magnetic stirrer was placed under argon a mixture of 6-bromo-2,2-dimethyl-1-hydroxyhexane (25 g, 0.119 mol), dichloromethane (300 ml) and p-toluenesulfonic acid (0.15 g, 0.78 mmol). 3,4-Dihydro-2H-pyran (12.57 g, 0.1495 mol) was added slowly to the mixture at 0° C. The reaction mixture was stirred at room temperature for one hour, and then the mixture was filtered through aluminum oxide, which was further washed with dichloromethane (200 ml). The combined fractions were evaporated under vacuum to provide 33.73 g (97%) of the above-titled compound as a pale-yellow residue, ca. 90%: 1H NMR CDCl3, δ (ppm): 4.48-4.52 (m, 1H), 3.90-3.75 (m, 1H), 3.50-3.35 (m, 4H), 2.95 (d, J=12 Hz, 1H), 1.90-1.20 (m, 12H), 0.90 (s, 6H); 13C NMR CDCl3, δ (ppm): 99.0, 76.2, 61.8, 38.2, 34.0, 33.8, 33.6, 30.5, 25.5, 24.5, 24.4, 22.5, 19.3.

1. customIn a 500 ml three-neck flask fitted with a condenser and magnetic stirrer
2. filtrationthe mixture was filtered through aluminum oxide, which
3. washwas further washed with dichloromethane (200 ml)
4. customThe combined fractions were evaporated under vacuum