N-bromobutanimide → 2-Bromo-3-ethoxycyclopent-2-enone

Participants

Reaction Steps

3-Ethoxy-cyclopent-2-enone (Intermediate NINE1) (commercially available from Aldrich) (10.0 g, 77.6 mmol) in carbon tetrachloride (15 mL) at 0° C. was treated with NBS (15.3 g, ˜85 mmol) added portion-wise over 30 m. After 1 h at 0° C. the mixture was partitioned between CH2Cl2 and saturated NaHCO3. The aqueous layer was extracted with CH2Cl2. The pooled organic layers were washed with H2O (2×) and dried over MgSO4. The mixture was filtered and evaporated to dryness. The solid was recrystallized from pentane:ether to give 13.3 g of 2-bromo-3-ethoxy-cyclopent-2-enone (Intermediate NINE2).

Provenance & Evidence