Solvent-Free DABCO-Mediated [3 + 2] Cycloadditions of Donor–Acceptor Cyclopropanes with Aldehydes: Strategy for Synthesis of Fully Substituted Furans

DABCO-mediated [3 + 2] cycloadditions of donor–acceptor cyclopropanes with aldehydes under solvent-free conditions have been developed for the preparation of fully substituted furans which are a wide range of structurally interesting and pharmacologically significant compounds. The reaction appears to be general for a variety of 1-cyanocyclopropane-1-carboxylates and aldehydes and tolerates the presence of aromatic moieties with electron-withdrawing and electron-donating substituents.