Regioselective arylations silver® carbonate

Regioselective functionalization of unreactive carbon-hydrogen bonds, in particular, arylation of pyridines by using aryl iodide, silver acetate, and catalytic palladium acetate 06SL3382. 

The mechanism likely involves the initial formation of the ruthenacycle with regioselective insertion of alkyne into the Ru(II)-C bond with addition of the Ru (II) site to the aryl carbon atom, and insertion of the carbonyl group into the Ru(II)-C bond. The resulting intermediate gives indenols on protonation or benzofulvenes on dehydration with an excess of silver salt (Scheme 24) [195]. 

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