Dmitry Tsvelikhovsky - Palladium-Catalyzed Cross-Alkynylation of Aryl Bromides by Sodium Tetraalkynylaluminates

Version 1

      Publication Details (including relevant citation   information):

      Dmitri Gelman, Dmitry Tsvelikhovsky, Gary A. Molander, and   Jochanan Blum

      J. Org. Chem.,  2002, 67 (18), pp 6287–6290

      Publication Date (Web): August 15, 2002   (Article)

      DOI: 10.1021/jo020169q

     

      Department of Organic Chemistry, The Hebrew University, Jerusalem   91904, Israel, and Roy and Diana Vagelos Laboratories, Department   of Chemistry, University of Pennsylvania, Philadelphia,   Pennsylvania 19104-6323

      Abstract:

      Sodium tetraalkynylaluminates, prepared from NaAlH4 and terminal alkynes, cross-couple   with aryl bromides in the presence of Pd(0) and Pd(II) catalysts.   The reactions take place in boiling THF or DME. The process is   applicable to both ****- and heterocyclic aryl bromides and can   be used for conversion of polybromo compounds into polyalkynes.   The reactions are high yielding and selective, free of undesired   homocoupling and hydrogenolysis processes. The reagents   selectively react with the ring-bound bromine atoms but do not   affect chloro, cyano, triflate, or ester functions.

      Address (URL): http://pubs.acs.org/doi/pdf/10.1021/jo020169q