Aromatic Iodination: Iodine and NaIO4 or NaIO3

[java]

Iodination of Both Deactivated and Activated Arenes with Sodium Periodate or Sodium Iodate as the Oxidant
Piotr Lulinski and Lech Skulski, Bulletin of the Chemical Society of Japan Vol. 73, No. 4, pp. 951-956 (2000)
DOI:

10.1246/bcsj.73.951

  (free pdf article)

Abstract
Five easy, relatively inexpensive, and environmentally-safe aromatic oxidative iodination procedures are presented; three of them are particularly suitable for deactivated arenes. Nine deactivated arenes, four halobenzenes, benzene, toluene, and N,N-dimethylaniline were reacted upon with the following anhydrous systems: diiodine/NaIO4 or (in four cases) NaIO3/acetic anhydride/glacial acetic acid, acidified with varying amounts of concd (98%) sulfuric acid; the following workups are explained. The aromatic oxidative iodination reactions proceeded mostly at room temperature and within 1—8 h to give fifteen mono- and two diiodinated purified products (sometimes obtained in 2—3 different ways) in 51—95% yields.

[Rhodium]

Eco-friendly Oxidative Iodination of Various Arenes with a Urea-Hydrogen Peroxide Adduct (UHP) as the Oxidant
Piotr Lulinski, Anna Kryska, Maciej Sosnowski, Lech Skulski

Synthesis 441-445 (2004)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/aromatic.iodination.urea-h2o2-i2.pdf)
DOI:

10.1055/s-2004-815955

Abstract
Three easy eco-friendly laboratory procedures are presented for the oxidative iodination of various activated and deactivated arenes with molecular iodine, in the presence of UHP (percarbamide), a stable, strongly H-bonded, solid urea-hydrogen peroxide adduct as the oxidant.

[demorol]

Oxidative Iodination of Arenes with Manganese(IV) Oxide or Potassium Permanganate as the Oxidants
Piotr Luliñski and Lech Skulski

Full text, available for free:

Bull. Chem. Soc. Jpn., 72, 115-120 (1999)

(http://www.jstage.jst.go.jp/article/bcsj/72/1/115/_pdf)

Abstract
Novel and easy laboratory methods (novel Procedures 1-4) are presented for the oxidative mono- and diiodination of both activated and deactivated arenes, which gave the pure iodinated products in 62-89% yields. The reactions were carried out in the anhydrous, strongly acidic medium, I₂/activated MnO₂/AcOH/Ac₂O/conc. H₂SO₄, firstly at r.t. for 2 h, then at 45-55°C for 2-9 h. The resulting mixtures were poured into excess aq Na₂SO₃ solution buffered with (NH₄)₂CO₃ to neutralize H₂SO₄. The following workups are given. Similarly, on carrying out the iodination reactions (at 35°C, for one hour) in the anhydrous, strongly acidic system, I₂/KMnO₄/AcOH/Ac₂O/conc. H₂SO₄, it was possible to mono- or diiodinate several deactivated arenes in 73-87% yields (improved Procedures 5 and 6).

[Kinetic]

Here's another simple iodination procedure from Synthesis. Aromatic amines are stable to the system, so maybe other amines are too.
It would be nice if this could complement Barium's work on the iodination of 2C-H (

Post 383499

(Barium: "A little 2C-I perhaps", Novel Discourse)):

Nonmetal-Catalyzed Iodination of Arenes with Iodide and Hydrogen Peroxide
Jernej Iskra,* Stojan Stavber, Marko Zupan, Synthesis 1869-1873 (2004)
DOI:

10.1055/s-2004-829136

Abstract
Oxidative iodination of arenes was carried out with one equivalent of KI and two equivalents of 30% hydrogen peroxide in MeOH in the presence of strong acid. Reactions of various substituted anisoles, phenols and anilines, as well as mesitylene and uracil, were selective and effective with very good yields of isolated halogenated aromatic molecules.

[Kinetic]

Tetrabutylammonium peroxydisulfate (made from tetrabutylammonium hydrogen sulfate and sodium peroxydisulfate) and iodine are used to iodinate phenol exclusively in the para- position in 92% yield. 1,4-Dimethoxybenzene is also monoiodinated in 92% yield.

The experimental from the following articles was posted some time ago by foxy2 in

Post 199741 (missing)

(foxy2: "Para-Selective Iodination of Methoxybenzenes", Chemistry Discourse), but the full articles fit nicely into this thread. The second article deals with the preparation of the oxidising agent:

A Practical Iodination of Aromatic Compounds Using Tetrabutylammonium Peroxydisulfate and Iodine
Seung Gak Yang and Yong Hae Kim*
Tetrahedron Letters, 40 (1999), 6051-6054

Abstract
A variety of aromatic compounds substituted with an electron donating group such as methoxy, hydroxy, or amino group, were regioselectively iodinated with iodine in the presence of tetrabutylammonium peroxydisulfate under mild conditions in excellent yields.

Novel Direct Tetrahydropyranylation of Alcohols with Tetrahydropyran and Tetra-n-butylammonium peroxydisulfate
Hyun Chul Choi, Kyu Il Cho, and Yong Hae Kim*
Synlett, 1995, 207-208

Another interesting method is the use of N-iodosaccharin for the iodination of arenes, and also - perhaps more interestingly - for the hypoiodination of alkenes to give iodohydrins in excellent yields:

N-Iodosaccharin - a New Reagent for Iodination of Alkenes and Activated Aromatics
Darko Dolenc
Synlett, 2000, 544-546

Abstract
A mild and efficient iodination reagent, N-iodosaccharin was prepared. Iodination of activated aromatics and alkenes with the reagent takes place fast and under very mild conditions, without the aid of strong acids or heavy metals. The reagent does not affect oxidizable groups, such as hydroxyl or aldehyde.

[Lego]

Simple and regioselective oxyiodination of aromatic compounds with ammonium iodide and Oxone®
K.V.V. Krishna Mohan, N. Narender, and S.J. Kulkarni
Tet. Lett., 2004, 45, 8015-8018
DOI:

10.1016/j.tetlet.2004.09.010

Abstract: A simple method for the iodination of aromatic compounds using NH₄I as the iodine source and Oxone® as the oxidant is described.



General procedure for the iodination of aromatic compounds: Oxone® (2.2 mmol) was added to a well-stirred solution of NH₄I (2.2 mmol) and substrate (2.0 mmol) in methanol (10 mL) and the reaction mixture was allowed to stir at room temperature. The reaction was monitored by thin layer chromatography (TLC). After completion of the reaction, the reaction mixture was filtered and solvent evaporated under reduced pressure. The products were purified by column chromatography over silica gel (finer than 200 mesh) with 5–30% ethyl acetate in hexane as eluent. All the structures of the products were confirmed by NMR and mass spectra.

[java]

Note:This has been inserted here from

Post 459094

(java: "Re: Novel easy preparations of Iodobenzene.....", Novel Discourse) to compliment this thread

Novel Easy Preparations of Some Aromatic Iodine(I, III, and V) Reagents, Widely Applied in Modern Organic Synthesis *

Lech Skulski

Molecules 8, 45-52,2003

http://www.mdpi.org/molecules/papers/80100045.pdf

Abstract:... We report our novel (or considerably improved) methods for the synthesis of aromatic iodides, (dichloroiodo)arenes, (diacetoxyiodo)arenes, [bis(trifluoroacetoxy)-iodo]arenes, iodylarenes and diaryliodonium salts, as well as some facile, oxidative anion
metatheses in crude diaryliodonium or tetraalkylammonium halides and, for comparison,potassium halides. All our formerly published papers were discussed and explained in our review ÒOrganic Iodine(I, III, and V) Chemistry: 10 Years of Development at the Medical University of Warsaw, PolandÓ (1990-2000) [1].