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A palladium (II)-catalyzed borono- ortho -CH activation/amination cascade for the construction of two C-N bonds and one C-C bond in a single synthetic sequence is reported. This method proceeds through a formal syn -carbopalladation of alkynes with organoboron compounds, forming alkenyl palladium species, which are trapped by simple amines to provide highly substituted indoles. Remarkably, with an electron-rich arylboronic acid, the reaction proceeds through an unexpected anti -carbopalladation terminated by ortho -CH activation of diarylalkyne/amination reaction to provide an unsymmetrically substituted 2,3-diaryl indole instead. In the follow-up chemistry, we demonstrate that urea participates in this cascade to offer a variety of free NH-indoles.

A highly regioselective and transition-metal free one-pot arylation of chromenones with arylboronic acids has been achieved employing K 2 S 2 O 8 . The procedure consists of a sequence of some reactions including an arylation/decarboxylation cascade and proceeds well in aqueous media to afford biologically interesting flavones and 3-arylcoumarins. This method exhibited excellent selectivity and functional group tolerance under mild conditions. The reaction also showed perfect efficacy for the preparation of styryl coumarins.

An approach to synthesize 2,3-diaryl benzo[b]furans using coumarins and aryl bromides is developed. This state-of-the-art strategy capitalizes on a palladium-catalyzed one-pot decarbonylative diarylation of coumarins, paving the way to achieve biologically interesting 2,3-diaryl benzo[b]furans.

A Catellani reaction terminated by palladacycle amination leading to methanocarbazoles is reported. The outcome is the formation of three different Csp(3)-Csp(2)/Csp(3)-N/Csp(2)-N bonds through a Heck reaction/C-H activation/double amination cascade in one process.

A new regioselective α-arylation of coumarins with unactivated simple arenes via a palladium-catalyzed twofold C-H functionalization is devised. This method offers an attractive new approach to synthesis of a wide variety of 3-arylcoumarins from readily accessible starting materials.

A straightforward and atom-economical base-free palladium-catalyzed regioselective direct arylation of coumarins and chromenones is devised. This protocol is compatible with a wide variety of electron-donating and -withdrawing substituents and allows construction of various biologically important flavone and neoflavone backbones.