Reactions of Some Furan-3-ones with 2,3-Diaminopyridine and its Derivatives

The furan-2-ylidene acetates (3a-d), obtained from the furan-2,3-diones (1a-b) and methyl/ethyl (triphenylphosphoranylidene)-acetates (2a-b), were converted via the Michael type reactions with 2,3-diaminopyridine and its derivatives (4a-c) into the corresponding pyrrol-2-ylidene-acetates (5a-j) in moderate yields (45-94%). Structures of these compounds were determined by the IR, NMR, elemental analysis, and X-ray diffraction method.