反应详情

To a solution of 4,5-dimethyl-cyclohexa-1,4-diene-1,2-dicarboxylic acid dimethyl ester (3.84 g, 17.1 mmol) in chlorobenzene was added 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (7.77 g, 34.2 mmol) at room temperature and the resulting mixture was heated to reflux 48 h. The resulting mixture was cooled and filtered through FLORISIL®. The pad of FLORISIL® was rinsed with diethyl ether and the filtrate filtered another (3×) through a pad of FLORISIL®. The filtrate was evaporated in vacuo to yield an amber syrup, which was purified via flash column chromatography (EtOAc/Heptane 4:1) to yield 4,5-dimethyl-phthalic acid dimethyl ester as a colorless oil.

1. temperaturethe resulting mixture was heated
2. temperatureto reflux 48 h
3. temperatureThe resulting mixture was cooled
4. filtrationfiltered through FLORISIL®
5. washThe pad of FLORISIL® was rinsed with diethyl ether
6. filtrationthe filtrate filtered another (3×) through a pad of FLORISIL®
7. customThe filtrate was evaporated in vacuo
8. customto yield an amber syrup, which
9. customwas purified via flash column chromatography (EtOAc/Heptane 4:1)