反应详情

0.13 Gram (1.85 mmol) propiolic acid is dissolved in 20 ml ether, under nitrogen, and the solution is cooled to -70°. 3.3 Milliliters of 1.1 M t-butyllithium (3.63 mmol) is added over a period of 1 hr, and the mixture is stirred for an additional hour at -60°. HMPA (10 ml) is added, followed by 0.32 g (1.96 mmol) 1-bromo-4-methyl-4-pentene (prepared as in either Example 1 or Example 3), keeping the solution cold. After 24 hr, the mixture is heated to 40°-45°. After 3 days, the reaction is worked up in 5% NaOH/ether, and the aqueous layer is extracted with ether. The basic phase is acidified with HCl and extracted with ether (2×). The latter ether phases are washed with water and brine, dried over Na2SO4, filtered and the solvent is removed to yield 7-methyl-7-octen-2-ynoic acid.

1. temperaturethe solution is cooled to -70°
2. customprepared as in either Example 1 or Example 3),
3. temperaturethe mixture is heated to 40°-45°
4. waitAfter 3 days
5. extractionthe aqueous layer is extracted with ether
6. extractionextracted with ether (2×)
7. washThe latter ether phases are washed with water and brine
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. customthe solvent is removed