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.
The catalytic cycle for the Heck reaction involves a series of transformations around the palladium catalyst. The palladium(0) compound required in this cycle is generally prepared in situ from a palladium(II) precursor.
For instance, palladium(II) acetate is reduced by triphenylphosphine to bis(triphenylphosphine)palladium(0) (1) and triphenylphosphine is oxidized to triphenylphosphine oxide. Step A is an oxidative addition in which palladium inserts itself in the aryl to bromide bond. Palladium then forms a π complex with the alkene (3) and in step B the alkene inserts itself in the palladium - carbon bond in a syn addition step. Then follows a torsional strain relieving rotation to the trans isomer (not shown) and step C is a beta-hydride elimination step with the formation of a new palladium - alkene π complex (5). This complex is destroyed in the next step. The palladium(0) compound is regenerated by reductive elimination of the palladium(II) compound by potassium carbonate in the final step, D. In the course of the reaction the carbonate is stoichiometrically consumed and palladium is truly a catalyst and used in catalytic amounts. A similar palladium cycle but with different scenes and actors is observed in the Wacker process.
In the presence of an ionic liquid a Heck reaction proceeds in absence of a phosphorus ligand. In one modification palladium acetate and the ionic liquid (bmim)PF6 are immobilized inside the cavities of reversed-phase silica gel. In this way the reaction proceeds in water and the catalyst is re-usable.
^Fujiwara, Yuzo; Noritani, Ichiro; Danno, Sadao; Asano, Ryuzo; Teranishi, Shiichiro (1969). "Aromatic substitution of olefins. VI. Arylation of olefins with palladium(II) acetate". Journal of the American Chemical Society91 (25): 7166. doi:10.1021/ja01053a047.
^Heck, Richard F. (1969). "Mechanism of arylation and carbomethoxylation of olefins with organopalladium compounds". Journal of the American Chemical Society91 (24): 6707. doi:10.1021/ja01052a029.
^Dieck, H. A.; Heck, R. F. (1974). "Organophosphinepalladium complexes as catalysts for vinylic hydrogen substitution reactions". Journal of the American Chemical Society96 (4): 1133. doi:10.1021/ja00811a029.
^Ozawa, F.; Kubo, A.; Hayashi, T. (1992). "Generation of Tertiary Phosphine-Coordinated Pd(0) Species from Pd(OAc)2 in the Catalytic Heck Reaction". Chemistry Lett. (11): 2177–2180. doi:10.1246/cl.1992.2177.
^De Vries, Johannes G. (2001). "The Heck reaction in the production of fine chemicals". Canadian Journal of Chemistry79 (5–6): 1086. doi:10.1139/cjc-79-5-6-1086.
^Hagiwara, Hisahiro; Sugawara, Yoshitaka; Hoshi, Takashi; Suzuki, Toshio (2005). "Sustainable Mizoroki–Heck reaction in water: remarkably high activity of Pd(OAc)2 immobilized on reversed phase silica gel with the aid of an ionic liquid". Chemical Communications (23): 2942–2944. doi:10.1039/b502528a. PMID15957033.