Hydrochloric Acid → 5-(Cyclopent-1-enyl)-2-methylpentan-2-ol

5-(Cyclopent-1-enyl)-2-pentanone (5.95 g; 39 mmol) in ethyl ether (6 ml) was added dropwise to a 3M solution of methylmagnesium bromide in the same solvent (17 ml; 51 mmol) during 15 minutes. After 2 hours at reflux, the mixture was cooled down to room temperature, poured into ice (20 g), acidified with 5N HCl (20 ml) and extracted with MTBE (60 ml). The aqueous phase was separated and extracted again with MTBE (2×100 ml). The combined organic phases were washed with saturated NaHCO3 (80 ml), H2O (80 ml), brine (80 ml), dried over MgSO4 and concentrated in vacuo. Bulb-to-bulb distillation (80° C./0.06 torr) yielded quantitatively 5.84 g of 5-(cyclopent-1-enyl)-2-methylpentan-2-ol containing 11% of 5-cyclopentylidene-2-methylpentan-2-ol.

1. temperatureAfter 2 hours at reflux
2. extractionextracted with MTBE (60 ml)
3. customThe aqueous phase was separated
4. extractionextracted again with MTBE (2×100 ml)
5. washThe combined organic phases were washed with saturated NaHCO3 (80 ml), H2O (80 ml), brine (80 ml)
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo
8. distillationdistillation (80° C./0.06 torr)

ORD record

ord-9586f4572e71411488278bbf89310e7c

Source dataset

uspto-grants-2002_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06399811B1