Sulfuric Acid → (1R,2R,5S)-2,6,6-trimethylbicyclo[3.1.1]heptan-3-one

Participants

Reaction Steps

add a mixture of 9 ml of H2SO4 and 40 ml of H2O to a solution of Cr2O3 (15.0 g, 0.15 mol) in H2O (20 mL) at 0° C. Add dropwise the above Jones reagent to a solution of (1R,2R,3R,5S)-2,6,6-trimethylbicyclo[3.1.1]heptan-3-ol (23.1 g, 0.15 mol) in acetone (100 mL) over a period for 2 hours at 0° C. Stir the resultant mixture for additional 1 hour. Dilute the mixture with 100 mL of water and then extract the aqueous mixture with ether (50 mL×3). The combined organic layers are washed with brine (20 mL), dried over Na2SO4, filtered, and concentrated under vacuum to give crude (1R,2R,5S)-2,6,6-trimethylbicyclo[3.1.1]heptan-3-one as pale yellow oil (21.3 g, yield: 93.4%), MS (m/z): 151 (M−1).

Provenance & Evidence