An oxidative procedure for the electrophilic iodination of phenols was developed by using iodosylbenzene as a nontoxic iodine­(III)-based oxidant and ammonium iodide as a cheap iodine atom source. A totally controlled monoiodination was achieved by buffering the reaction medium with K3PO4. This protocol proceeds with short reaction times, at mild temperatures, in an open flask, and generally with high yields. Gram-scale reactions, as well as the scope of this protocol, were explored with electron-rich and electron-poor phenols as well as heterocycles. Quantum chemistry calculations revealed PhII­(OH)·NH3 to be the most plausible iodinating active species as a reactive “I+” synthon. In light of the relevance of the iodoarene moiety, we present herein a practical, efficient, and simple procedure with a broad functional group scope that allows access to the iodoarene core unit.

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The first gold(I)-catalyzed cycloisomerization procedure applied to the synthesis of substituted 4 H -benzo[ d ][1,3]oxazines has been developed starting from N -(2-alkynyl)aryl benzamides. The chemoselective oxygen cyclization via the 6- exo -dig pathway yielded the observed heterocycles in modest to good chemical yields under very mild reaction conditions. The obtained oxazines were assayed on the breast cancer (BC)-derived cell lines MCF-7 and HCC1954 with differential biological activity. The newly synthesized 4 H -benzo[ d ][1,3]oxazine compounds showed several degrees of cell proliferation inhibition with a remarkable effect for those compounds having a substituted aryl at C-2 of the molecules. The 4 H -benzo[ d ][1,3]oxazines showed an IC 50 ranking from 3.1 to 95 μM in MCF-7 and HCC1954 cells. These compounds represent potential drug candidates for BC treatment. However, additional assays are needed to elucidate their complete effect over the cellular and molecular hallmarks of cancer.

In memory of KevinThe first iodine(III)-mediated para-selective iodination protocol for free anilines as well as the mechanistic elucidation of the reaction pathway is described. The developed method proceeded under clean, non-toxic, efficient, and in general mild reaction conditions. To the best of our knowledge this report describes for the first time a procedure focused specifically on the introduction of an iodine atom in free anilines using PIDA [(diacetoxyiodo)benzene] and ammonium iodide which formed in situ acetyl hypoiodite (AcO-I) as the halogenating species. Our DFT calculations suggest a reaction mechanism that highlights the catalytic role of the ammonium cation in the AcO-I formation and halogenation. Considering there are few procedures for the iodine atom introduction in anilines using non-acidic conditions, herein we described an initial report on a mild and operationally simple alternative using iodine(III) reagents.

: Iodine(III)-based reagents has been broadly used in oxidative reactions for the structural functionalization with several functional groups. Among the more relevant and useful synthetic transformations using these hypervalent γ 3 -reagents, it can be found the fluorination, chlorination, bromination as well as the iodination protocols. Herein, we present some of the most representatives oxidative halogenation procedures of arenes, olefins and alkynes dating from the oldest to the more recent advances in the area, highlighting the discovery and application of new iodine(III)-based halogenating species.