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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