2- or 3-Alkynylpyridines were prepared using a palladium complex, in the absence of copper ions or amines. The mild procedure tolerated a range of 1-alkynes giving 2- or 3-alkynylpyridine in moderate to good yield.
(a) SonogashiraK., TohdaY., and HagiharaN., Tetrahedron Lett., 1975, 16, 4467; (b) L. Cassar, J. Organomet. Chem., 1975, 93, 253; (c) H.A Dieck and F.R. Heck, J. Organomet. Chem., 1975, 93, 259.
2.
For reviews, see: (a) SonogashiraK. In Comprehensive Organic Synthesis, TrostB.M, and FlemingI., (eds.) Pergamon Press, New York, 1991, vol. 3, 521; (b) R. Rossi, A. Carpita and F. Bellina, Org. Prep. Proc. Int., 1995, 27, 129; (c) J. Tsuji, Palladium Reagents and Catalysts. Wiley, Chichester, 1995, p. 168; (d) K.C. Nicolaou and E.J. Sorensen, Classics in Total Synthesis. VCH, Weinheim, 1996, p. 582; (e) L. Brandsma, S.F. Vasilevsky and H.D. Verkruijsse, Application of Transition Metal Catalysts in Organic Synthesis, Springer, Berlin, 1998, p. 179; (f) K. Sonogashira In Metal-Catalysed Cross-Coupling Reactions, F. Diederich and P.J. Stang, (eds.) Wiley-VCH, Weinheim, 1998, p. 203.
3.
For examples using aryl bromides in the Sonogashira reaction, see: (a) LemhadriM., DoucetH., and SantelliM., Synthesis, 2005, 1359; (b) M. Lopez-Deber, L. Castedo and J. Granja, Org. Lett., 2001, 3, 2823; (c) M. Unroe and B. Reinhardt, Synthesis, 1987, 981; (d) L. Bleicher N. Cosford A. Herbaut, J. McCallum and I. McDonald, J. Org. Chem., 1998, 63, 1109; (e) M. Inouye, K. Fujimoto M. Furusyo and H. Nakazumi, J. Am. Chem. Soc., 1999, 121, 1452; (f) A. Basak, J. Shain, K. Khamrai, K Rudra and A. Basak, J. Chem. Soc., Perkin Trans. 1, 2000, 1955.
(a) ChengJ., WangF., XuJ., PanY., and ZhangZ., Tetrahedron Lett., 2003, 44, 7095; (b) J. Cheng, Y. Sun, F. Wang, J. Xu, Y. Pan and Z. Zhang, J. Org. Chem, 2004, 69, 5428.
6.
MukaiyamaT., KikuchiW., and ShintouT., Chem. Lett., 2003, 32, 300.
7.
LemhadriM., DoucetH., and SantelliM., Synthesis, 2005, 1359.
8.
NovakZ., SzaboA., RepasiJ., and KotschyA, J. Org. Chem., 2003, 68, 3327.
9.
ErdelyiM., and GogollA., J. Org. Chem, 2001, 66, 4165.
10.
NagyT., CsampaiA., and KotschyA., Tetrahedron, 2005, 61, 9767.
11.
LiP., WangL., and LiH., Tetrahedron, 2005, 61, 8633.
