Ruthenium(II)-catalyzed C(3)–H arylation of furan moiety in fuberidazole derivatives

Simple Access to 3-(Hetero)arylated Derivatives of 2-Furoic Acid via Ru(II)-Catalyzed C3-H Arylation of 2-Furoylimidazole

“…We started the study with the arylation of compound 1a bearing the imidazolecarbonyl DG with aryl halides 7a – c (Tables 1 and Table S1 in the SI). Under previously reported conditions, 22 arylation with 4-bromotoluene ( 7a ) in the presence of [RuCl 2 ( p -cymene)] 2 (5 mol%) in 1,4-dioxane at 110 °C gave only a 21% NMR yield of desired product 8a (Table 1 , entry 1). The addition of carboxylic acids (serving as carboxylate proligands) to promote C–H bond activation via the concerted metalation-deprotonation (CMD) 23 mechanism resulted in an increase in the yield of 8a up to 37–79% (entries 2–6).…”