ChemInform Abstract: An Efficient One-Pot Synthesis of Dialkyl 3H-Naphtho[2,1,b]pyran-2,3-dicarboxylates Mediated by Vinyl Triphenylphosphonium Salt

Protonation of the reactive intermediates produced in the reaction between dialkyl acetylenedicarboxylates and triphenylphosphine by 2-hydroxy-1-naphthaldehyde leads to vinyltriphenylphosphonium salts, which undergo intramolecular Wittig reaction to produce dialkyl 3H-naphtho[2,1-b]pyran-2,3-dicarboxylates in fairly high yields. ∗Dedicated to Professor Abbas Shafiee on the anniversary of his 60th birthday.