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2-Iodoxybenzoic acid (IBX) is a mild and versatile oxidant. It can be easily prepared from 2-iodobenzoic acid and Oxone (See the Dess-Martin oxidation as reference).
IBX had long been rarely used as a reagent because of its poor solubility in organic solvents other than DMSO. New interesting reactions are being explored recently by Nicolaou and others.
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The addition of water is known to decrease the reactivity, which is rationalized by the reversible ligand exchange mechanism. (ref: J. Am. Chem. Soc. 2005, 127, 14146.)
Whereas the Dess-Martin reagent cleaves 1,2-diols, IBX can oxidize them without breaking them up.
IBX is also useful to prepare α,β-unsaturated ketones.
It can also oxidize benzylic methyl groups into aldehydes.
The oxidation of amines to imines is also possible with IBX.
The oxidation to carboxylic acids is possible by adding N-hydroxysuccinimide. The functional group selectivity is high.[5a] Using Oxone as a reoxidant under heating conditions, IBX can be substoichiometric.[5b]
Selective oxidation of secondary hydroxyl groups in the presence of primary hydroxyl groups is possible.
2-Iodobenzenesulfonic acid acts as a highly active oxidation catalyst. It forms a sulfonic acid analogue of IBX in situ.
The conversion of amides into nitriles with one-carbon dehomologation.
IBX has well-known for its hazard risks as a potential explosive. Special caution is required when carrying out the reaction on a large scale.
 (a) Mazitschek, R.; Mulbaier, M. M.; Giannis, A. Angew. Chem. Int. Ed. 2002, 41, 4059. [abstract] (b) Thottumkara, A. P.; Bowsher, M. S.; Vinod, T. K. Org. Lett. 2005, 7, 2933. DOI: 10.1021/ol050875o
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 Bhalarao, D. S; Mahajan, U. S.; Chaudhari, K. H.; Akamanchi, K. G. J. Org. Chem. 2007, 72, 662. DOI: 10.1021/jo0619074
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