Cyclohexadienone ketals and quinols: Four building blocks potentially useful for enantioselective synthesis

An overview is given of the preparations and applications of MOB-ketals, 0-quinols, MPB-ketals, and p-quinols. The diastereoselective syntheses testify to the usefulness of these compounds as intermediates. Chiral auxiliaries and derivatizations have been used with success for the production of these types of nonracemic cyclohexadienones. The more recent asymmetric catalytic methods bode well for future enantioselective applications.