Unexpected regiocontrol in the Pauson–Khand reaction due to 2-furyl substitution of the alkene component

Abstract

2-Vinylfuran derivatives undergo regiocontrolled Pauson–Khand reaction, in which the furan exerts the dominant directing influence, to furnish 5-(2-furyl)cyclopent-2-enones, overwhelming the strong directing effects of a homoallylic thioether and appearing to inhibit intramolecular reaction in which bridging constraints are in opposition to the directing influence of the 2-furyl substituent.