Hypervalent iodine (V) catalyzed reactions

Abstract

The chemistry of hypervalent iodine compounds has been widely recognized in the synthetic community. The utilization of hypervalent iodine compounds as stoichiometric reagents as well as catalysts has tremendously been studied in recent decades. Hypervalent iodine (V)-catalyzed reactions are proven to be versatile catalytic systems to access various oxidative transformations. In this review, the versatility of hypervalent iodine (V)catalyzed reactions have been discussed in detail. This review highlights the oxidation of various substrates using catalytic amounts of o-iodoxybenzoic acid (IBX), modified IBX derivatives, o-iodoxybenzenesulfonic acid (IBS), recyclable iodine (V), and non-cyclic/pseudocyclic iodine (V) compounds.

Organohypervalent heterocycles

“…333,[612][613][614] 615 Later, Mullin and coworkers reported the synthesis of IBX through the oxidation of 2-iodobenzoic acid using potassium bromate under acidic conditions. 616 However, the existence of bromate impurities imparted explosive nature to IBX at elevated temperature; thus, IBX could not be developed as a potential oxidant, especially for many years until the synthetic method reported by Frigerio et al 617 Since then, IBX has been utilized in a plethora of oxidative transformations, involving the oxidation of alcohols, amines, benzylic carbon and phenols 333,[612][613][614] and oxidative cyclization to diverse heterocyclic rings has been welldocumented. 618 A. R. Katritzky and coworkers confirmed the cyclic structure of IBX derivatives by X-ray crystallographic study.…”

New Isoxazole‐Substituted Aryl Iodides: Metal‐Free Synthesis, Characterization and Catalytic Activity

“…[7][8] Besides the use of hypervalent iodine reagents as stoichiometric reagents, the catalytic use of hypervalent iodine compounds has received much attention in recent years. [9][10] The first hypervalent iodine-catalyzed reaction for electro-chemical gem-difluorination of dithioacetals was reported by Fuchigami and Fujita in 1994. [11] Initially, peracetic acid and some common inorganic oxidants were used, however, m-chloroperbenzoic acid (m-CPBA) was effectively employed for the in-situ generation of hypervalent iodine reagents by the oxidation of iodoarenes.…”

“…[14] Subsequently, various reports appeared in the literature regarding iodoarene-catalyzed organic transformations by the use of terminal oxidants. [2,10,15] The oxidation of hydroquinone and sulfides to their corresponding oxidized products is one of the most studied oxidation reactions. During the oxidation of sulfides, most reagents necessitate carefully controlled reaction conditions including the quantity of oxidants because of the formation of sulfones as side products.…”

“…These reagents have been extensively explored for the various oxidative transformations such as oxidation of alcohols, [3] phenols, [4] sulfides, [5] and C−H functionalization [6] and for the oxidative cyclization to form various heterocyclic moieties [7–8] . Besides the use of hypervalent iodine reagents as stoichiometric reagents, the catalytic use of hypervalent iodine compounds has received much attention in recent years [9–10] . The first hypervalent iodine‐catalyzed reaction for electro‐chemical gem‐difluorination of dithioacetals was reported by Fuchigami and Fujita in 1994 [11] .…”

“…The first hypervalent iodine‐catalyzed reaction using m ‐CPBA as a terminal oxidant was independently reported by groups of Ochiai, [12] Kita [13] and Vinod [14] . Subsequently, various reports appeared in the literature regarding iodoarene‐catalyzed organic transformations by the use of terminal oxidants [2,10,15] . The oxidation of hydroquinone and sulfides to their corresponding oxidized products is one of the most studied oxidation reactions.…”