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The intermolecular C–H cross-coupling between aromatic ethers has been achieved for the first time using perfluorinated hypervalent iodine(III) compounds as extreme single-electron-transfer (SET) oxidants. The demonstrations of this specific coupling could provide a direct route to valuable oxygenated mixed naphthalene-benzene biaryls 3only, without formation of other biaryl-derived byproducts. [ABSTRACT FROM AUTHOR]

The expeditious and efficient [3 2] coupling approach of quinone monoacetals 1with alkene nucleophiles 2by the action of an activated Brønsted acid in the presence of a hydrogen bond donor perfluorinated alcohol has been achieved. With the optimized combined acid, the reaction could proceed under mild conditions by only mixing the two reactants to afford the cycloadducts 3in a short time (within 10 min) with good to quantitative yields. [ABSTRACT FROM AUTHOR]

We have succeeded in the first versatile iodoarene-catalyzed C−C bond-forming reactions by development of a new reoxidation system at low temperatures using stoichiometric bis(trifluoroacetyl) peroxide A in 2,2,2-trifluoroethanol (TFE). The catalytic system supplies a wide range of substrates and functional availabilities sufficient to be used in the key synthetic process of producing biologically important Amaryllidaceae alkaloids. [ABSTRACT FROM AUTHOR]

A series of electron-rich bipyrroles were prepared by the regioselective, phenyliodine(III) bis(trifluoroacetate) (PIFA) induced oxidative coupling of pyrroles in the presence of bromotrimethylsilane. Using pyrrole and 3,4-disubstituted pyrroles gave exclusively 2,2'-linked bipyrroles without the formation of other bipyrrole regioisomers. The 3-alkyl- or 3-aryl-substituted pyrroles gave unsymmetrical H-T dimers in high yields as the major isolable ?-linked bipyrrole products over the symmetrical H-H dimers. The nature of the N-substituent significantly influences the regioselectivity of the reaction, thus regiocontrolled bipyrrole coupling of N-phenyl- and N-benzyl-substituted pyrroles gave 2,3'-bipyrroles. [ABSTRACT FROM AUTHOR]

We have developed a new and reliable method for the direct construction of biologically important aryl lactones and phthalides from carboxylic and benzoic acids, using a combination of hypervalent iodine(III) reagents with KBr. [ABSTRACT FROM AUTHOR]

We have found that the use of fluoroalcohol media greatly enhanced the efficiency and scope of the direct dehydrative condensation of arenes 1 and hypervalent iodine(iii) compounds; the present clean method has a broad range of applicability as well as unique selectivity in the aromatic substrates, and is highly efficient even in polymer functionalization. [ABSTRACT FROM AUTHOR]

A protic solvent, 2,2,2-trifluoroethanol (CF3CH2OH), was successfully introduced into hypervalent iodine(iii)-involved catalytic cycles as an effective solvent, and the first iodoarene-catalyzed intramolecular carbon–nitrogen bond forming reaction was achieved under strong acid-free and mild conditions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Iodonium(III) salts bearing uracil moieties have recently appeared in the literature, but their structural scope and utilization are limited because of their hygroscopic characteristics. In this study, we describe our detailed investigations for synthesizing a series of uracil iodonium(III) salts derived with various structural motifs and counterions. These new compounds have been utilized as attractive synthetic modules in constructing functionalized nucleobase and nucleosides.