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The reaction of alkynyl p-quinone methide (pQM) with keto-methylenes through a base-mediated tandem 1,6-addition/annulation sequence, [2 + 3] annulation, affording the furans is reported for the first time. A variety of functionalized furans, including fused derivatives, were obtained in good to excellent yields under mild reaction conditions. The efficacy of alkynyl pQMs is highlighted by extending their use to access isoxazoles, pyrazoles via[3 + 2] annulation, and pyridines through [3 + 3] annulation in the presence of different bis-nucleophiles.

An efficient intramolecular annulation of Morita–Baylis–Hillman (MBH) alcohols of propiolaldehydes is developed in the presence of ICl or PhSeSePh/PhSSPh–CuCl2. This cyclization offers access to a wide variety of iodinated or chalcogenated 3-(chloromethyl)-2-pyrones in good yields. The chloromethyl group of the obtained 2-pyrones has been easily converted to introduce other handy functionalities, which allowed for further transformations to synthesize diverse 2-pyrone containing molecules.