Ytterbium Triflate Promoted Coupling Reaction Between Aryl Alkynes and Aldehydes

Abstract

A simple and efficient solvent-free coupling reaction affording regioselectively trans-α,β-enones from aryl alkynes and aldehydes catalysed by Yb(OTf)₃ hydrate is described.

Key words

aldehydes - alkynes - catalysis - coupling - lanthanides

References

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11

Typical Procedure: To a mixture of aldehyde (1.0 mmol) and aryl alkyne (2.0 mmol), Yb(OTf)₃ (0.1 mmol) was added and stirring was continued at 90 °C for 12 h. To this mixture CH₂Cl₂ (2 mL) was added at r.t., the solid precipitated was filtered under vacuum, the filtrate dried over Na₂SO₄ and evaporated. The residue was purified by SiO₂ gel column chromatography using petroleum ether-EtOAc 9:1 as eluent, to give the desired product.

12

Identified by comparison with a commercial sample.