2-Cyclopenten-1-one → HCID 66902515, compound

Participants

Reaction Steps

To a suspension of (ethoxycarbonylmethyl)dimethyl sulfonium bromide (134 g, 585 mmol) in 486 mL of acetonitrile at room temperature is added 87.4 mL (585 mmol) of 1,8-diazabicyclo[5.4.0]undec-7-ene dropwise over 15 minutes. After stirring for 1 hour, the yellow mixture is treated with 40 g (487 mmol) of 2-cyclopenten-1-one over 10 minutes. The mixture is allowed to stir over night at which time 480 mL of tert-butyl methyl ether is added, followed by washing with 1N hydrochloric acid (1×240 mL). The aqueous layer was washed with tert-butyl methyl ether (1×240 mL). The combined organic extracts were washed with brine (1×400 mL), dried (MgSO4), filtered, and concentrated in vacuo to provide crude ethyl (6S)-2-oxobicyclo[3.1.0]hexane-6-carboxylate as an orange solid (84.8 g). The crude material may be purified through distillation (138° C., 10 mm Hg), followed by slurrying the solidified distillate in heptane, filtering, and drying.

Provenance & Evidence