Reaction of Dianions of Acyclic β-Enamino Ketones with Electrophiles. Part 2. Oxiranes: Synthesis of γ'- and ε-Hydroxy-β-enamino Ketones and of α-Tetrahydrofurylidene Ketones.
β-Monoalkylamino-α,β-unsaturated ketones can be regioselectively dimetallated either at the α'- or in the γ-positions.The reaction of the resulting dianions with oxiranes proceeds in good to high yields affording the corresponding hydroxyalkyl derivatives