Asymmetric Synthesis of Bicyclo[2.2.2]oct-5-en-2-one by Using Organocatalysis

Significance

Jørgensen and co-workers report an unexpected Michael-aldol-Smiles rearrangement sequence for the preparation of 6-substituted bicyclo[2.2.2]oct-5-ene-2-ones 4 with high enantioselectivity. The corresponding Michael ­adducts 3 of cyclohexenone and β-keto benzo­thiazoyl sulfones 1 can be easily cyclized under mild ­reaction conditions. The authors also performed various transformations on the obtained bicyclic compounds, such as ring-expanding Baeyer-Villiger oxidation, Schmidt reaction and rearrangement reactions.