Base‐Promoted One‐Pot Synthesis of Phthalans from 1,3‐Enynyl Alcohols and Allylic(propargylic) Bromides

Abstract A synthetic method that relies on base‐promoted allylation(propargylation)/propargyl‐allenyl isomerization/dehydro‐Diels−Alder cascade of 1,3‐enynyl alcohols for the synthesis of structurally diverse phthalan derivatives under metal‐free mild reaction conditions is described. Moreover, the protocol could be further expanded to the synthesis of 3,5‐disubstituted‐5,7‐dihydrofuro[3,4‐ b ]pyridines simply by changing the allyl or propargyl bromides to 2‐bromoacetonitrile.