Heck reaction, Myers’ decarboxylative

Our original mechanism for decarboxylative reactions included a mmiometallic palladium catalyst related to that postulated in 2002 by Myers for his oxidative decarboxylative Heck reactions (Scheme 3) [6]. 

Scheme 4 Proposed mechanism for Myers decarboxylative Heck reaction...

Myers oxidative decarboxylative Heck reaction became the prototype for a whole series of regiospecific oxidative couplings in which carboxylic acids adopt the reactivity of aryl electrophiles in the corresponding redox-neutral processes [67-72]. Crabtree et al. developed a process in which arenes react with aromatic carboxylates under C-H activation in the presence of a palladium catalyst and excess silver carbonate to yield biaryls. This reaction is useful especially for intramolecular couplings (Scheme 20) [73, 74]. Recently, a palladium-free, silver-catalyzed radical variant has been disclosed [78]. 

Myers AG, Tanaka D, Mannion MR (2002) Development of a decarboxylative palladation reaction and its use in a Heck-type olefination of arene carboxylates. J Am Chem Soc 124 11250-11251... 

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