Chemoselective cross-coupling reactions with differentiation between two nucleophilic sites on a single aromatic substrate.

A new thiophene building block, containing both a stannyl group and a boronic ester, was prepared. From this starting material, a general, nucleophile-selective one-pot reaction was developed, exploiting the different reactivities of the Stille and Suzuki-Miyaura cross-coupling reactions. A series of aromatic electrophiles were used to demonstrate the high functional group tolerance.