Synthesis and Utility of 2,2-Dimethyl‑2H‑pyrans: Dienes for Sequential Diels–Alder/Retro-Diels–Alder Reactions

The practical use of 2,2-dimethyl-2H-pyrans as electron-rich dienes in sequential Diels–Alder/retro-Diels–Alder (DA/rDA) domino processes to generate aromatic platforms has been demonstrated. Different polysubstituted alkyl 2-naphthoates have been synthesized by the DA/rDA reaction of benzynes and 2,2-dimethyl-2H-pyrans. The use of other activated alkynes allows the access of substituted alkyl benzoate derivatives.