Oxalic Acid → (RS)-2-methyl-4-methylidene-3-ethylcyclopent-2-en-1-ol

After 4.0 g of (RS)-2-methyl-4-methylidene-3-ethyl-1-t-butyldimethylsilyloxy-2-cyclopentene was dissolved in 35 ml of dry tetrahydrofuran, 17.5 ml of a 1M tetrabutylammonium fluoride/tetrahydrofuran solution was added under cooling and stirred at ambient temperatures for twelve hours. The reaction solution was then added to 100 ml of an ice-cooled 5% aqueous oxalic acid, and extracted with diethyl ether (300 ml×3 times). The combined ether layer was washed successively with a saturated sodium hydrogencarbonate solution and a saturated sodium chloride solution, and dried over anhydrous magnesium sulfate. After removal of the solvent under reduced pressure, the residue was treated by silica gel column chromatography (eluent: n-hexane:ethyl acetate=3:1 (v/v)) to yield 2.0 g of (RS)-2-methyl-4-methylidene-3-ethylcyclopent-2-en-1-ol. Yield 92%

1. temperatureunder cooling
2. extractionextracted with diethyl ether (300 ml×3 times)
3. washThe combined ether layer was washed successively with a saturated sodium hydrogencarbonate solution
4. dry with materiala saturated sodium chloride solution, and dried over anhydrous magnesium sulfate
5. customAfter removal of the solvent under reduced pressure
6. additionthe residue was treated by silica gel column chromatography (eluent: n-hexane:ethyl acetate=3:1 (v/v))

ORD record

ord-26e29a31b8fe437cb4fa6fc6ce5e7f56

Source dataset

uspto-grants-1997_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05672779