反应详情

To a solution of dimethyl 2,2-dimethylpentanedioate from Step A (25.4 g, 135 mol) in MeOH (150 mL), THF (100 mL) and water (100 mL), was added potassium carbonate (36.2 g, 262 mmol). This biphasic solution was allowed to stir for 68 h, at ambient temperature, after which time the reaction was about 50% complete. Solvents were carefully removed in vacuo such that the starting materials did not vaporize. The aqueous layer was diluted with water (266 mL) and then extracted with diethyl ether until no additional SM was detected in the aqueous layer. The aqueous layer was made acidic by the addition of 6 M HCl (95 mL), and was then saturated with NaCl. This aqueous layer was extracted once with diethyl ether (250 mL). This ethereal layer was washed with brine, then dried over sodium sulfate, filtered and concentrated in vacuo to give the title compound. MS: m/z=175 (M+1).

1. customSolvents were carefully removed in vacuo such that the starting materials
2. additionThe aqueous layer was diluted with water (266 mL)
3. extractionextracted with diethyl ether until no additional SM
4. additionThe aqueous layer was made acidic by the addition of 6 M HCl (95 mL)
5. extractionThis aqueous layer was extracted once with diethyl ether (250 mL)
6. washThis ethereal layer was washed with brine
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated in vacuo