Double Elimination Protocol for the Synthesis of Arylene Ethynylenes Containing Heteroaromatic Rings

The double elimination reaction of β-substituted sulfones offers a versatile strategy for synthesis of arylene ethynylene kits containing heteroaromatic rings. A sequence of aldol reaction between α-sulfonyl carbanion and aldehyde, trapping the resulting aldolate to give β-substituted sulfone, and double elimination of this intermediate can be integrated in one pot. This protocol allows thiophene, pyridine, and ferrocene units to be accommodated in phenylene ethynylene arrays.Key words: arylene–ethynylenes, heteroaromatic rings, ferrocene, double elimination, sulfones.