Catalysis Sonogashira reaction

The coupling of terminal alkynes with aryl or vinyl halides under palladium catalysis is known as the Sonogashira reaction. This catalytic process requires the use of a palladium(0) complex, is performed in the presence of base, and generally uses copper iodide as a co-catalyst. One partner, the aryl or vinyl halide, is the same as in the Stille and Suzuki couplings but the other has hydrogen instead of tin or boron as the metal to be exchanged for palladium. 

However, the real breakthrough in this area is due to the development of catalysis by transition metals, with the Heck, Suzuki, Sonogashira reactions and other related coupling process. ... 

Cross-coupling of aryl and vinyl halides with terminal acetylenes (the Sonogashira reaction) is among the fundamental methods of Pd-catalyzed C-C bond forming reactions. Cu-Pd co-catalysis is considered a standard requirement for this method. 

Monohgated oxazolines derived from commercially available 2-ethyl-2-oxazoUne can form trans-square-planar palladium complexes by simple treatment of this ligand with inorganic palladium salts in methanolic solutions (Scheme 6.15) [72]. The catalysis, when performed in pyrrolidine, gave a yield of 32%, which corresponded to a TON of 190. The Sonogashira reaction was carried out under aerobic conditions with no precautions to exclude moisture from the solvent or substrates. 

Since aikenes and aikynes can be prepared via Heck and Sonogashira reactions, respectively, tandem processes are also possible for lactone synthesis [71-77]. Appropriately, o-iodobenzoic acids can generate both phthalide and isocoumarin derivatives under Pd catalysis, with a Cul co-catalyst favoring the former and... 

Future avenues of research will focus on heterogeneous catalysis whereby highly active catalysts can be easily recycled and reused. Application has already begun in the established reactions such as Suzuki-Miyaura, Mizoroki-Heck and Sonogashira reactions. Over time it is expected that new C-H activation reactions will succumb to designed nanoparticle catalysis. Researchers in the field of total synthesis are... 

The coupling of terminal alkynes 25 with aryl or vinyl halides under palladium catalysis is known as the Sonogashira reaction. The catalytic process... 

Starting from l-(2-ethynylquinolin-3-yl)ethanone 140, available by subsequent Sonogashira reaction from 2-chloroquinoline, the Grignard reaction with MeMgBr to give a secondary alcohol, and Dess—Martin periodinane oxidation, a method was developed which provided 1-aminoacridines 141 (Scheme 53). On addition of secondary amines, enamines E formed under TiCl4 catalysis (method A), in the presence of molecular sieves... 

I 2 Bridging the Cap between Homogeneous and Heterogeneous Catalysis 1.1.1 A Sonogashira Reaction... 

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