Pd-PEPPSI-IPent: Low-Temperature Negishi Cross-Coupling for the Preparation of Highly Functionalized, Tetra-ortho-Substituted Biaryls

Cool couplings: Complex, hindered biaryls have been prepared at temperatures ranging from 0°C to room temperature, or with gentle heating. The Pd‐PEPPSI‐IPent catalyst (see scheme) nicely couples starting materials containing acidic moieties and routinely prepares biaryl derivatives where one or both rings comprising the biaryl are heterocyclic. Ar1=hindered aryl or heteroaryl, Ar2=unactivated aryl or heteroaryl.