Facile synthesis of acetylene-substituted terthiophenes

A modified Horner–Emmons condensation reaction has been employed for the synthesis of acetylene-substituted terthiophenes in excellent yields. Conjugating 3′-aryl substituents to terthiophene using an ethyne rather than an ethene linker results in enhanced planarity of the resulting molecule as established by X-ray structural analysis of (2,2′:5′,2″-terthiophen-3′-yl)-4‴-pyridylethyne.