反应详情

A solution of the product of example 8, part b), (1.6 g), N-bromosuccinimide (1 g), and azoisobutyronitrile (10 mg) in ethyl acetate (25 ml) was refluxed for 1 h. The solution was cooled to room temperature, washed successively with dilute sodium hydroxide solution and water, the organic extracts were dried over anhydrous magnesium sulfate, filtered and evaporated under reduced pressure. The residue was purified by column chromatography over silica, eluting with diethyl ether/i-hexane (1:1) to give the sub-title compound as a solid (1.5 g). δ 1HCDCl3 1.62 (6H, d), 3.37 (3H, s), 3.99 (3H, s), 3.60-3.70 (3H, m)

1. washwashed successively with dilute sodium hydroxide solution and water
2. dry with materialthe organic extracts were dried over anhydrous magnesium sulfate
3. filtrationfiltered
4. customevaporated under reduced pressure
5. customThe residue was purified by column chromatography over silica
6. washeluting with diethyl ether/i-hexane (1:1)