3,4-DIEXOMETHYLENE TETRAHYDROPYRANE DERIVATIVES WHICH ARE USEFUL AS INTERMEDIATE FOR PREPARING TWO OR THREE CYCLIC COMPOUNDS THROUGH DIELS-ALDER REACTION AND PROCESS FOR PREPARING THE SAME

摘要

PURPOSE: 3,4-Diexomethylene tetrahydropyrane derivatives and a process for preparing the same derivatives are provided, which derivatives are useful as intermediate for preparing two or three cyclic compounds through Diels-Alder reaction. CONSTITUTION: The 3,4-diexomethylene tetrahydropyrane derivatives represented by formula (1) are provided, wherein R1 and R2 are selected from hydrogen, C1-C10 optionally saturated linear, branched chain or cyclic alkyl, and aromatics. The process for preparing the 3,4-diexomethylene tetrahydropyrane derivatives of formula (1) comprises reacting 1-substituted-3-trimethylsilanylmethyl-3,4-pentadiene-1-ol derivatives of formula (2) with aldehyde derivatives of formula (3) in solvent in the presence of Lewis acid catalyst at -100 deg. C to room temperature, wherein the Lewis acid catalyst is selected from trimethylsillyl trifluoromethanesulfonate(TMSOTF), aluminium halide, indium(III) halide, boron halide and titanium(IV) halide; and the solvent is selected from dimethylether, diethylether and tetrahydrofuran.