A straightforward copper-free palladium methodology for the selective alkynylation of a wide variety of S-, O-, and N-based mono- and diheterocyclic bromides and chlorides

作者：Saleh Samer; Picquet Michel; Meunier Philippe; Hierso Jean Cyrille^*

来源：Tetrahedron, 2009, 65(34): 7146-7150.

DOI：10.1016/j.tet.2009.06.009

High-yield alkynylations are successfully achieved by a simple and widely accessible catalytic system for an unprecedented variety of heterocyclic bromides and chlorides in position -2, -3 or -5: pyridine, quinoline, thiophene, furan, thiazole, benzothiazole, pyrimidine, pyridazine, pyrazine, dioxepin halides are efficiently functionalized in short time reactions. This copper-free methodology employs 1 mol% palladium only, with inexpensive PPh(3) and amine base. The ionic liquid solvent allows a straigtforward separation of products and recycling opportunity. Unsuitable substrates and secondary reactions are also reported in order to point out further progress in cross-coupling using ionic liquids.

• 出版日期2009-8-22