Dimethyl Sulfoxide → 6-Bromo-2-oxabicyclo[2.2.1]heptan-3-one

Participants

Reaction Conditions

Reaction Steps

Bromotrimethysilane (3.1 mL, 0.023 mol) was added dropwise to a solution of dimethyl sulfoxide (1.6 mL, 0.023 mol) in chloroform (38.0 mL) in a round-bottom flask at 0° C. The resulting mixture was stirred at 0° C. for 2 hours. To the reaction mixture was added dropwise a solution of cyclopent-3-ene-1-carboxylic acid (2.00 g, 0.0178 mol) in chloroform (12 mL) over a period of 15 minutes and the reaction mixture was stirred at 0° C. for 10 minutes. N,N-diisopropylethylamine (4.0 mL, 0.023 mol) was then added and the resulting mixture was stirred at 0° C. After 10 minutes, the mixture was heated to reflux for 16 hours. The reaction mixture was diluted with chloroform, washed with water, brine, dried (MgSO4), and stripped in vacuo. The residue was purified by chromatography on silica gel using 30% EtOAc/hexanes as eluent to give the product. 1H NMR (400 MHz, CDCl3): δ 4.88 (brs, 1H), 4.34 (m, 1H), 2.90 (m, 1H), 2.66 (m, 1H), 2.31 (m, 1H), 1.93 (m, 1H), 1.83 (m, 1H).

Provenance & Evidence