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The Heck reaction (also called the Mizoroki-Heck reaction) is the chemical reaction of an unsaturated halide (or triflate) with an alkene in the presence of a base and a palladium catalyst (or palladium nanomaterial-based catalyst) to form a substituted alkene. It is named after Tsutomu Mizoroki and Richard F. Heck. Heck was awarded the 2010 Nobel Prize in Chemistry, which he shared with Ei-ichi Negishi and Akira Suzuki, for the discovery and development of this reaction. This reaction was the first example of a carbon-carbon bond-forming reaction that followed a Pd(0)/Pd(II) catalytic cycle, the same catalytic cycle that is seen in other Pd(0)-catalyzed cross-coupling reactions. The Heck reaction is of great importance, as it allows one to do substitution reactions on planar sp2-hybridized carbon atoms. The reaction is performed in the presence of an organopalladium catalyst. The halide (Br, Cl) or triflate is an aryl, benzyl, or vinyl compound and the alkene contains at least one hydrogen and is often electron-deficient such as acrylate ester or an acrylonitrile.The catalyst can be tetrakis(triphenylphosphine)palladium(0), palladium chloride or palladium(II) acetate. The ligand is triphenylphosphine, PHOX or BINAP. The base is triethylamine, potassium carbonate or sodium acetate. Several reviews have been published. ==History== The original reaction by Tsutomu Mizoroki (1971) describes the coupling between iodobenzene and styrene to form stilbene in methanol at 120°C (autoclave) with potassium acetate base and palladium chloride catalysis. This work was an extension of earlier work by Fujiwara (1967) on the Pd(II)-mediated coupling of arenes (Ar–H) and alkenes and earlier work by Heck (1969) on the coupling of arylmercuric halides (ArHgCl) with alkenes using a stoichiometric amount of a palladium(II) species. The 1972 Heck publication acknowledged the Mizoroki publication and detailed ''independently discovered'' work. The reaction conditions differ in catalyst used (palladium acetate) and catalyst loading (0.01 eq.), base used (a hindered amine) and lack of solvent. In these reactions the active catalyst Pd(0) (see reaction mechanism) is formed by Pd coordination to the alkene. In 1974 Heck introduced phosphine ligands into the equation. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Heck reaction」の詳細全文を読む スポンサード リンク
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