反应详情

Cyclopentadiene, which was obtained by thermolysis of dicyclopentadiene, was dissolved in a conventional organic solvent, and the solution was cooled to about −30° C. About 1 equiv. of cooled acryl acid was slowly added to the solution. The reaction mixture was stirred for about 10 hours, after which the reaction mixture was allowed to reach room temperature and stirred for additional 10 hours. The solvent was removed using a rotary evaporator, and 5-norbornene-2-carboxylic acid was obtained by vacuum distillation. About 1 mole of 5-norbornene-2-carboxylic acid and about 1 mole of thionyl chloride were slowly combined and agitated in a bath. The remaining or unreacted thionyl chloride was removed and about 1 mole of triethylamine and 4-(2-hydroxyethyl)morpholine were added to the mixture. The reaction mixture was extracted with ethyl acetate. And the organic layer was separated, dried over anhydrous MgSO4, and concentrated to provide the title compound represented by formula 1a in 75% yield.

1. customThe remaining or unreacted thionyl chloride was removed
2. extractionThe reaction mixture was extracted with ethyl acetate
3. customAnd the organic layer was separated
4. dry with materialdried over anhydrous MgSO4
5. concentrationconcentrated