A sequential one-pot classical aldol, transition-metal and hydride-free reductive aldol reaction has been reported for C(sp3)-H functionalization of 2-oxindoles using multifaceted reagent rongalite. Here, rongalite functions as a hydride-free reducing...

A transition-metal and hydride-free reductive aldol reaction has been developed for the synthesis of biologically active 3,3´-disubstituted oxindoles from isatin-derivatives using rongalite. In this protocol, rongalite plays the dual role...

A transition metal- and hydride-free protocol has been developed for the chemoselective reduction of α-keto esters and α-keto amides using rongalite as a reducing agent. Here, rongalite acts as a hydride-free reducing agent via a radical mechanism. This protocol offers the synthesis of a wide range of α-hydroxy esters and α-hydroxy amides with 85–98% yields. This chemoselective method is compatible with other reducible functionalities such as halides, alkenes, amides, and nitriles. The use of inexpensive rongalite (ca. $0.03/1 g), mild reaction conditions, and gram-scale synthesis are some of the key features of this methodology. Also, cyclandelate, a vasodilator drug, has been synthesized in gram scale with 79% yield.

A molecular iodine catalyzed regioselective insertion of isocyanide into C2-H of quinoline N-oxides has been developed. The reaction proceeds through the nucleophilic addition of isocyanide on quinoline Noxides followed by rearrangement in presence of iodine. This metal-free reaction affords rapid access to quinoline 2-formamides with exceptional functional group tolerance, broad substrate scope and 100% atomeconomy. A library of 33 N-(2-quinolinyl)formamides are synthesized, which may find applications in pharmaceuticals and synthetic chemistry.

No abstract