Hypervalent Iodine Compounds
Weaker and longer than covalent linkages, hypervalent bonds are the result of a linear three-center, four-electron (3c-4e) electronic distribution (hypervalent model). Hypervalent iodine reagents are useful synthetic tools due to their low toxicity, ready availability, and ease of handling.
Specific hypervalent iodine reagents: Dess-Martin Periodinane, Iodosobenzene diacetate, Iodosobenzene bis(trifluoroacetate), Iodosylbenzene, 2-Iodoxybenzoic Acid, Iodobenzene Dichloride
Recent Literature
[dibmim][BF4] can be used for the oxidation of alcohols to
carbonyl compounds. This oxidizing agent offers a high degree of selectivity
for the oxidation of primary alcohols to carbonyl compounds without
oxidation to carboxylic acids in ionic liquids. [dibmim][BF4] can
be reused after oxidation with peracetic acid.
W. Qian, E. Jin, W. Bao, Y. Zhang, Angew. Chem., 2005,
117, 974-977.
Stable, microcrystalline 2-iodylphenol ethers were prepared by the
dimethyldioxirane oxidation of the corresponding 2-iodophenol ethers.
2-Iodylphenol ethers can selectively oxidize sulfides to sulfoxides and alcohols
to the respective aldehydes or ketones.
A. Y. Koposov, R. R. Karimov, I. M. Geraskin, V. N. Nemykin, V. V. Zhdankin, J. Org. Chem., 2006,
71, 8452-8458.
A mild, efficient and environmentally friendly oxidation of sulfides to
sulfoxides with a recyclable ion-supported hypervalent iodine reagent tolerates
hydroxyl, nitrile, methoxy, carbon-carbon double bonds, and ester
functionalities. Aliphatic and aromatic sulfides are selectively oxidized to the
corresponding sulfoxides at room temperature in excellent yields without
over-oxidation.
W. Qian, L. Pei, Synlett,
2006, 709-712.
Various α-tosyloxyketones were efficiently prepared in high yields from the
reaction of ketones with m-chloroperbenzoic acid and p-toluenesulfonic acid in
the presence of a catalytic amount of iodobenzene.
Y. Yamamoto, H. Togo, Synlett,
2006, 798-800.
α-Acetoxylation of ketones catalyzed by iodobenzene using^acetic anhydride and
30% aqueous hydrogen peroxide as the oxidant is an effective and economical
method for the preparation of α-acetoxy ketones in good yields.
J. Sheng, Y. Li, M. Tang, B. Gao, G. Huang, Synthesis, 2007,
1165-1168.
Poly{[4-(hydroxy)(tosyloxy)iodo]styrene} was efficient in the halotosyloxylation
reaction of alkynes with iodine or NBS or NCS. The polymer reagent could be
regenerated and reused.
J.-M. Chen, X. Huang, Synthesis, 2004,
1557-1558.
