Potassium Hydroxide → 5-Norbornene-2-carboxylic acid

27.5 g (110 mmol) of the Diels-Alder adduct obtained in the above step was dissolved in 420 ml of a mixture solvent of tetrahydrofuran-water (5:2), on ice cooling, 30.0 g (455 mmol) of potassium hydroxide (85%) in 120 ml of water was added, and the mixture was stirred at room temperature for 24 hours. After distilling off tetrahydrofuran, the residue was neutralized with 40 ml of concentrated hydrochloric acid, and the solution was extracted with a mixture solvent of hexane-methylene chloride (98:2) (150 ml×4). The extract was dried over anhydrous magnesium sulfate and filtered, the solvent was distilled off, and 15.7 g of crude 5-norbornene-2-carboxylic acid was obtained. Crude yield: 100%.

1. additionwas added
2. distillationAfter distilling off tetrahydrofuran
3. extractionthe solution was extracted with a mixture solvent of hexane-methylene chloride (98:2) (150 ml×4)
4. dry with materialThe extract was dried over anhydrous magnesium sulfate
5. filtrationfiltered
6. distillationthe solvent was distilled off

ORD record

ord-d0a400947286491490acb03e2d1d0101

Source dataset

uspto-grants-1993_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05266728