Sonogashira Coupling

This coupling of terminal alkynes with aryl or vinyl halides is performed with a palladium catalyst, a copper(I) cocatalyst, and an amine base. Typically, the reaction requires anhydrous and anaerobic conditions, but newer procedures have been developed where these restrictions are not important.

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Mechanism

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Recent Literature

The First Applications of Carbene Ligands in Cross-Couplings of Alkyl Electrophiles: Sonogashira Reactions of Unactivated Alkyl Bromides and Iodides
M. Eckhardt, G. C. Fu, J. Am. Chem. Soc., 2003, 125, 13642-13643.

Modified Palladium-Catalyzed Sonogashira Cross-Coupling Reactions under Copper-, Amine-, and Solvent-Free Conditions
Y. Liang, Y.-X. Xie, J.-H. Li, J. Org. Chem., 2006, 71, 379-381.

Application of recoverable nanosized palladium(0) catalyst in Sonogashira reaction
P. Li, L. Wang, H. Li, Tetrahedron, 2005, 61, 8633-8640.

Copper- and Ligand-Free Sonogashira Reaction Catalyzed by Pd(0) Nanoparticles at Ambient Conditions under Ultrasound Irradiation
A. R. Gholap, K. Venkatesan, R. Pasricha, T. Daniel, R. J. Lahoti, K. V. Srinivasan, J. Org. Chem., 2005, 70, 4869-4872.

Efficient Copper-Free PdCl₂(PCy₃)₂-Catalyzed Sonogashira Coupling of Aryl Chlorides with Terminal Alkynes
C. Yi, R. Hua, J. Org. Chem., 2006, 71, 2535-2537.

Efficient Palladium-Catalyzed Coupling of Aryl Chlorides and Tosylates with Terminal Alkynes: Use of a Copper Cocatalyst Inhibits the Reaction
D. Gelman, S. L. Buchwald, Angew. Chem. Int. Ed., 2003, 42, 5993-5996.

Copper-Free Sonogashira Coupling Reaction with PdCl₂ in Water under Aerobic Conditions
B. Liang, M. Dai, J. Chen, Z. Yang, J. Org. Chem., 2005, 70, 391-393.

Sonogashira Coupling Reaction with Diminished Homocoupling
A. Elangovan, Y.-H. Wang, T.-I. Ho, Org. Lett., 2003, 5, 1841-1844.

Carbamoyl-Substituted N-Heterocyclic Carbene Complexes of Palladium(II): Application to Sonogashira Cross-Coupling Reactions
R. A. Batey, M. Shen, A. J. Lough, Org. Lett., 2002, 1411-1414.

Single-Isomer Tetrasubstituted Olefins from Regioselective and Stereospecific Palladium-Catalyzed Coupling of β-Chloro-α-iodo-α,β-unsaturated Esters
A. B. Lemay, K. S. Vulic, W. W. Ogilvie, J. Org. Chem., 2006, 71, 3615-3618.

The coupling of acid chlorides with terminal alkynes using one equivalent of triethylamine under Sonogashira conditions followed by subsequent addition of amines or amidinium salts to the intermediate alkynones allows a straightforward access to enaminones and pyrimidines under mild conditions and in excellent yields.
A. S. Karpov, T. J. J. Müller, Synthesis, 2003, 2815-2826.