A new method for the preparation of 2,3-cycloalkeno-5,6-cycloalkeno-4H-pyran-4-ones

Several 2,3-cycloalkeno-5,6-cycloalkeno-4H-pyran-4-ones, such as 2,3,5,6-bicyclopenteno-4H-pyran-4-one and 1,2-dihydronaphtho[3,4-b]cyclopenteno[1,2-e]-4H-pyran-4-one, were synthesized conveniently by the reaction of a cyclic ketone enamine and diacylchloride. This reaction allows a new method for preparation of these compounds, which may be the precursors for the synthesis of some useful heterocycles.