Facile Synthesis of Silylated 4,5-Disubstituted Phthalates via Inverse Electron-demand Cycloaddition of 2-Pyrone-4,5-dicarboxylate with Silylacetylenes

A facile and efficient synthesis of silylated 4,5-disubstituted phthalates through the inverse electron-demand [4+2] cycloaddition of 2-pyrone-4,5-dicarboxylate with various silylacetylenes has been developed. The reaction was promoted by 4A molecular sieves (MS 4A) to afford the corresponding polysubstituted arenes with functionalizable silyl groups in good to high yield, thus providing versatile access to a wide variety of functionalized phthalates that represent promising intermediates for the synthesis of fine chemicals, particularly photochemically active compounds.