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.