Intramolecular Diels-Alder cycloadditions of 2-pyrones

The intramolecular Diels-Alder (IMDA) cycloadditions 05CR4779 02AC(E)1668 of 2-pyrones have not been exhaustively explored, due to the lack of synthetic methods to incorporate requisite tethered dienophiles. Only a few examples can be found in the literature and they have been employed mostly in the synthesis of aromatic compounds. 

Sdieme 38. IMDA cycloaddition of 154 with alkyl silane tether 

Scbeme 42. Synthesis and IMDA cycloadditions of 2-pyrones tethered with acrylamide 

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