反应详情

0.530 g (2.65 mmoles) of (Z)-8-Hydroxy-7,7-dimethyl-5-octenoic acid methyl ester in 5 ml of methylene chloride was added slowly to a mixture of CrO3 (2.1 g; 21 mmol) and pyridine (3.5 g; 42 mmol) suspended in 55 ml of methylene chloride at room temperature. The reaction mixture was stirred for 5 hrs. The dichloromethane phase was decanted, and the precipitate was washed three times with ether. The organic phases were combined, washed with chilled 1 N sodium hydroxide, 1 N sulfuric acid, saturated sodium bicarbonate solution and brine then dried (MgSO4) and concentrated to give 0.53 g of crude material. Purification by chromatography or a silica gel column afforded 0.405 g (77.1%) of pure (Z)-8-Oxo-7,7-dimethyl-5-octenoic acid methyl ester (100% pure, by GC-analysis).

1. customThe dichloromethane phase was decanted
2. washthe precipitate was washed three times with ether
3. washwashed
4. temperaturewith chilled 1 N sodium hydroxide, 1 N sulfuric acid, saturated sodium bicarbonate solution and brine
5. dry with materialthen dried (MgSO4)
6. concentrationconcentrated
7. customto give 0.53 g of crude material
8. customPurification by chromatography