A Palladium Catalyzed Environmentally Benign Acylation

Recent trends in research have gained an orientation towards developing efficient strategies using innocuous reagents. The earlier reported transition-metal catalyzed carbonylations involved either toxic carbon monoxide (CO) gas as carbonylating agent or functional group assisted ortho sp2 C-H activation (i.e. ortho acylation) or carbonylation by the activation of carbonyl group (i.e. via the formation of enamines). Contradicting to these methods, here we describe an environmentally benign process, [Pd]-catalyzed direct carbonylation starting from simple and commercially available iodo arenes and aldehydes, for the synthesis of a wide variety of ketones. Moreover, this method comprises direct coupling of iodo-arenes with aldehydes without the activation of carbonyl and also without directing group assistance. Significantly, the strategy was successfully applied to the synthesis n-butylphthalide and pitofenone