A new and in situ formed reagent generated by mixing PIFA {bis[(trifluoroacetoxy)iodobenzene]} and AlCl3 was introduced in the organic synthesis for the direct and highly regioselective ortho‐chlorination of phenols and phenol ethers. An efficient electrophilic chlorination for these electron‐rich arenes as well as the scope of the reaction are described herein. An easy, practical, and open‐flask reaction allowed us to introduce a chlorine atom, which is a highly important functional group in organic synthesis. The reproducibility of our method has been demonstrated on gram‐scale by carrying out the reaction in 6‐bromo‐2‐naphthol. This halogenation reaction also proceeds in excellent conditions by first preparing the iodine(III)‐based chlorinating reagent. Our new chlorinating reagent can be stored at least for two weeks at 4 °C without losing its reactivity.

A practical electrophilic bromination procedure for the phenolic core was developed under efficient and very mild reaction conditions. The new I(iii)-based brominating reagent PhIOAcBr operationally easy to prepare by mixing PIDA and AlBr3 was used.

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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<p>A series of new 3,4-diarylmaleimides were synthesized in an optimized and efficient lineal sequence of three steps, starting from commercial maleimide. The biological evaluation of these compounds as enhancers (activity modulators) in the co-administration with doxorubicin treatment in breast cancer cells directly obtained from a patient, were essayed. The cancerous tissue BT026-512N was provided by the National Institute of Cancerology (INCAN) of México. This tissue was obtained by biopsy from a patient diagnosed with stage IIB ductal breast cancer. The results obtained in the assays, show decreased cell viability on the cultured cells for all of the maleimides synthesized in combinatorial administration with doxorubicin. The highest mortality effect was determined for maleimides <strong>9</strong> and <strong>29</strong> increased in close to three times the effect compared with treatment using only doxorubicin. Based on previous functionalized maleimides core reports and Molinspiration chemoinformatic analysis, these results could possibly point out to the Pg-p glycoprotein as bio-molecular action target of maleimides by kinase phosphorylation-inhibition, although more experimental data is necessary.</p>

The chemoselective reaction of the C-followed by the O-centered naphthyl radicals with the more electron-deficient hypervalent bond of the diaryliodonium(III) salts is described. This discovered reactivity constitutes a new activation mode of the diaryliodonium(III) salts which enabled a one-pot doubly arylation of naphthols through the sequential C 2 sp-C 2 sp /O-C 2 sp bond formation. The naphthyl radicals were generated in the reaction by the tetramethylpiperidinyl radical (TMP•) which resulted from the homolytic fragmentation of the precursor TMP 2 O. Experimental and DFT calculations provided a complete panorama of the reaction mechanism.

: 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.