The Directed ortho Metalation (D o M)-Cross-Coupling Connection: Synthesis of Polyfunctional Biaryls

A comparative evaluation of the combined directed ortho metalation (DoM)-Suzuki-Miyaura and DoM-Negishi cross-coupling reactions with aryl triflates for the synthesis of substituted biaryls is described. Both ortho-zinc and ortho-boron aryl directed metalation group (DMG = CON(i-Pr)(2), OCONEt2, OMOM, NHBoc) substrates were evaluated. The superiority of the DoM-Negishi over the DoM-Suzuki-Miyaura reaction in operational convenience and mild reaction conditions is noted. Orthogonal Negishi and Suzuki-Miyaura with Corriu-Kumada reactions for the synthesis of a teraryl derivative is also reported.