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In contast to the general [4+2] cycloaddition reactions of alkynylcyclopropane ketones reported in the literature, we report herein a Sc(OTf)3-catalyzed formal intermolecular [3+2] cycloaddition reaction of alkynylcyclopropane ketones with electron-rich aromatic aldehydes. 2,3,3,5-Tetrasubstituted tetrahydrofurans were obtained by this method, and the tetrahydrofuran skeleton was diastereoselectively constructed with a 2,5- trans configuration. This is also quite different to the 2,5- cis configuration usually obtained from typical [3+2] cycloaddition reactions of most donor-acceptor cyclopropanes. Additionally, the cycloadducts were subjected to a domino carbopalladation/C-H activation/C-C bond-formation process for the highly efficient construction of polycyclic skeletons. [ABSTRACT FROM AUTHOR]