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In recent years the chemistry of cyclic iodonium salts has experienced ever-growing development. The advantages of using cyclic iodonium salts over acyclic iodonium salts are that the reactions between cyclic iodonium salts and various nucleophiles lead, under suitable reaction conditions, to dual arylations in a one-pot manner and to the formation of new heterocycles. Variously functionalized thiophenes, carbazoles, fluorenes, phenanthrenes and triazolophenanthridines have been synthesized by utilizing cyclic diaryliodonium salts. Various new ladder-type p-conjugated systems have also been synthesized by employing cyclic iodonium salts. In this microreview, the recent advancements in the synthesis and application of cyclic diaryliodonium salts are discussed in a systematic and concise manner. [ABSTRACT FROM AUTHOR]

Both hypervalent organoiodine(III) compounds and boronic acids/esters are non-toxic and considered as environment-friendly compounds and have had a remarkable impact on the field of synthetic organic chemistry. Numerous transformations have been carried out using hypervalent organoiodine(III) or boronic acids/esters - taken separately - with other reactants, but transformations with these two reagents taken together are comparatively less well reported. In this mini-review, diverse reactions carried out with these two substrates in the presence of each other, have been discussed. Various functionalizations of boronic compounds, promoted by hypervalent organoiodine(III) reagents, both in the presence and absence of transition metals, have been reviewed. Different metal-free iodine(III)-boron exchange reactions providing iodonium salts, various ipso transformations of boronic acids/esters and metal-catalyzed cross-coupling reactions of boronic compounds with hypervalent organoiodine(III) reagents are the prime focal areas of this article. Mechanistic aspects for certain reactions have also been delineated. [ABSTRACT FROM AUTHOR]

An efficient, metal and base-free, chemoselective synthesis of aryl-, heteroaryl-, and alkyl primary amines from the corresponding boronic acids has been achieved at ambient temperature mediated by [bis(trifluoroacetoxy)iodo]benzene (PIFA) and N-bromosuccinimide (NBS) using cyanamidyl/arylcyanamidyl radicals as the aminating species. The primary amine compounds were initially obtained as their corresponding ammonium trifluoroacetate salts which, on treatment with aq NaOH, provide the free amines. Finally, the primary amines were isolated through column chromatography over silica-gel using hexane-EtOAc solvent system as the eluent. The reactions are sufficiently fast, completing within 1 h. Quantum chemical calculations in combination with experimental observations validate that the ipso amination of substituted boronic acids involves the formation of cyanamidyl/arylcyanamidyl radical, followed by regiospecific interaction of its nitrile-N center with boron atom of the boronic acids, leading to chemoselective primary amination. [ABSTRACT FROM AUTHOR]

A new pathway to the synthesis of N-arylindoles has been developed that proceeds through an iron-catalyzed [2+2+2] cycloaddition reaction between diynes and indole-N-alkynes. The reaction is carried out in ethanol and employs a catalyst system that consists of iron(II) chloride tetrahydrate as the metal source, 2-[(2,6-diisopropylphenyl)iminometh-yl]pyridine (dipimp) as the ligand, and zinc as the reducing agent. The method provides efficient access to 3-carbonyl/ ester-substituted (indol-1-yl)arenes in good to excellent yields under green reaction conditions, and these products are structurally similar to other N-arylindole derivatives with potential medicinal value. [ABSTRACT FROM AUTHOR]

The reaction tolerates a broad range of aryl, hetaryl, and alkyl boronic acids which may contain diverse functional groups. [ABSTRACT FROM AUTHOR]

The article presents chemical equations for the article "An Eco-Friendly Route to N-Arylindoles by Iron-Catalyzed [2 + 2 + 2] Cycloaddition of Diynes with (Indol-1-yl)alkynes" by H. Chowdhury and others, published in the journal "Journal of Organic Chemistry" in 2015.

An abstract of the article "Metal and Base Free Synthesis of Primary Amines via ipso Amination of Organoboronic Acids Mediated by [Bis(trifluoroacetoxy)iodo]benzene (PIFA)" by N. Chatterjee and A. Goswami is presented.

A convenient oxidative ipso nitration of various functionalized organoboronic acids under mild reaction condition using a combination of PIFA, NBS, and sodium nitrite as nitro source is presented. [ABSTRACT FROM AUTHOR]

A novel methodology for the iodine-catalyzed ipso-hydroxylation of aryl and alkylboronic acids and esters is developed affording diversely functionalized aromatic and aliphatic alcohols. [ABSTRACT FROM AUTHOR]

An abstract of the article "Hydroxylation of Aryl- and Alkylboronic Acids/Esters Mediated by Iodobenzene Diacetate - An Avenue for Using Organoboronic Acids/Esters as Nucleophiles for Hydroxylation Reactions," by Nachiketa Chatterjee and colleagues is presented.