Oxidative Iodination of Deactivated Arenes in Concentrated Sulfuric Acid with I₂/NaIO₄ and KI/NaIO₄ Iodinating Systems [1]

Abstract

Deactivated arenes were mono- or diiodinated with strong electrophilic I⁺ reagents, which were prepared from NaIO₄ and either I₂ or KI in concentrated H₂SO₄ (minimum 95% by weight). In general a small excess of the dark brown iodinating solution was used (1.1/1.5 equivalents, for nitrobenzene two equivalents was required). The iodinations were conducted at 25-30 °C with a reaction time of 1-2 hours using either a ‘direct’ or an ‘inverse’ method of aromatic iodination to give mono- or diiodinated pure products in 31-91% optimized yields.

Key words

iodoarenes - deactivated arenes - iodine - potassium iodide - sodium periodate - direct oxidative iodination

1

These results were partly presented at the 8^th International Electronic Conference on Synthetic Organic Chemistry, paper A024, November 1-30, 2004.

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1

These results were partly presented at the 8^th International Electronic Conference on Synthetic Organic Chemistry, paper A024, November 1-30, 2004.