Table 2. Synthesis of Multisubstituted Furans (3) from 2-(Aziridin-2-ylmethylene)malonate or 1,3-Dione (2) with BF₃·OEt₂^a.

^aReaction conditions: 1,3-dione 2 (1.0 equiv) and BF₃·OEt₂ (1.05 equiv) in CH₂Cl₂ (0.3 M) at rt.

^bStarting ketone 2p was prepared in situ and directly converted to furan derivative 3p.