A Domino Strategy for the Synthesis of 2H-Pyrans from Propargyl Vinyl Ethers

Article abstract of DOI:10.1002/ejoc.201801847

Stable monocyclic 2H-pyrans are synthesized from readily available tertiary propargyl vinyl ethers via a metal-free all-pericyclic domino manifold involving a sequential propargyl Claisen rearrangement/[1,3]H-shift/oxa-6π electrocyclization set of reactions. The wide scope of this protocol is exemplified by the synthesis of 21 different 2H-pyrans incorporating a varied substitution pattern at the ring.