Tetrahedron

Regioselectivity in alkenyl (aryl)-heteroaryl Suzuki cross-coupling reactions of 2, 4-dibromopyridine. A synthetic and mechanistic study

C Sicre, JL Alonso-Gómez, MM Cid

Index: Sicre, Cristina; Alonso-Gomez, J.-Lorenzo; Cid, M. Magdalena Tetrahedron, 2006 , vol. 62, # 48 p. 11063 - 11072

Full Text: HTML

Citation Number: 27

Abstract

2, 4-Dibromopyridine undergoes a regioselective Suzuki cross-coupling reaction at position 2 with several alkenyl (aryl) boronic acids to render 4-bromo-2-carbon substituted pyridines, difficult to be prepared otherwise, in good yields under palladium catalysis, either Pd (PPh3) 4/TlOH or Pd2dba3/PCy3/K3PO4 at 25° C. This behavior is explained on the basis of the electrophilic character of both C–Br bonds, being their relative reactivity in 2, 4- ...