Sequence of alkylation of cyclohexane-1, 3-dione. Alternative synthesis of (±)-Angustione

A method is proposed for introducing one, two, or three alkyl substituents into positions 4 and 6 of the cyclohexane-1, 3-dione molecule by successive alkylation under the action of strong bases. (±)-Angustione (a natural β-diketone) has been synthesized.