反应详情

A mixture of 5.0 g (0.017 mole) of (3R-cis)-3-(4,6-dihydroxychroman-3-ylmethyl)benzoic acid methyl ester (prepared by esterification of the corresponding carboxylic acid (prepared according to the method of co-pending U.S. Pat. Application of Murtiashaw, et al., U.S. Ser. No. 07/964,336 filed Oct. 21, 1992) and 1.0 g palladium hydroxide in 100 mL glacial acetic acid was shaken in a Parr hydrogenator under 50 psi hydrogen at room temperature for 3 hours. The mixture was filtered through Celite and the filtrate concentrated to give an oil. Flash chromatography on silica gel eluting with 5% methanol in dichloromethane yielded 4.3 g (81% of the title product as an oil). NMR (CDCl3): δ2.30 (m, 1H); 2.50 (dd, 1 ,H) ; 2.75 (m, 3H); 3.80 (dd, 1H); 3.92 (s, 3H); 4.15 (dd, 1H). MS (Cl, NH3) m/e: 316 (100).

1. customprepared
2. filtrationThe mixture was filtered through Celite
3. concentrationthe filtrate concentrated
4. customto give an oil