反应详情

A portion (3.3 g) of the compound obtained in Example 22 was dissolved in anhydrous tetrahydrofuran (THF; 400 ml) and to the solution was added o-chloranil (3.6 g). The resulting mixture was stirred for 30 minutes at room temperature. After adding 1N aqueous solution of sodium hydroxide, the reaction mixture was extracted twice with ethyl acetate. The organic layers were combined, washed twice with 1N aqueous solution of sodium hydroxide and once with saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. Then, the solvent was distilled off under reduced pressure and the residue was purified by silica gel column chromatography (methylene chloride) and further crystallized from an ether/hexane mixed solvent to yield 2.3 g (70%) of the titled compound as crystals.

1. extractionthe reaction mixture was extracted twice with ethyl acetate
2. washwashed twice with 1N aqueous solution of sodium hydroxide and once with saturated aqueous solution of sodium chloride
3. dry with materialdried over anhydrous sodium sulfate
4. distillationThen, the solvent was distilled off under reduced pressure
5. customthe residue was purified by silica gel column chromatography (methylene chloride)
6. customfurther crystallized from an ether/hexane mixed solvent