High Pressure Mediated Diels-Alder Reaction of Furan with Dialkyl (Acetoxymethylene)malonate

Article abstract of DOI:10.1021/jo00258a012

The Diels-Alder reaction of furan with dialkyl (acetoxymethylene)malonates 1 did not proceed even in the presence of Lewis acid catalysts under conventional conditions.However, the reaction under high pressure (1.1 GPa) gave the expected cycloadducts, dialkyl 3-acetoxy-7-oxabicyclo<2.2.1>hept-5-ene-2,2-dicarboxylates 2.The bis-, tris-, and tetrakisadducts 3-6 were also produced in some amounts.Similar high-pressure reactions in the presence of zinc iodide as a catalyst yielded dialkyl 2-furfurylidenemalonate 8, and none of the adducts were obtained.