Selective reduction of C=C double bond of the Lactone ring

The aim of the current work is development of the novel methods for the selective reduction of the double bond of lactone ring in 3-substituted 2-oxo-25-dihydrofurans and 2-oxo-56-dihydropyrns as well as the synthesis of new derivatives of unsaturated γ-lactones on the basis of relatively accessible compounds of butenolide class with the aim of searching for the biological activity among the synthesized structures.Two reducing systems –“magnesium-methanol” and “sodium borohydride-triethylamine” – are proposed for the selective reduction of C=C double bond of the lactone ring.