Categories: I-O Bond Formation >
Synthesis of hypervalent iodine(III) compounds
Sodium hypochlorite pentahydrate (NaClO·5H2O) enables an inexpensive, safe, and rapid oxidation of iodoarenes to provide synthetically useful (diacetoxyiodo)arenes as precursors of various organo-λ3-iodanes such as hydroxyl(tosyloxy)iodobenzene, iodosylbenzene, iodonium ylide, etc.
A. Watanabe, K. Miyamoto, T. Okada, T. Asawa, M. Uchiyama, J. Org. Chem., 2018, 83, 14262-14268.
The use of oxone in trifluoroacetic acid enables a general and convenient synthesis of [bis(trifluoroacetoxy)iodo]arenes at room temperature. The oxidation of perfluoroalkyl iodides gives [bis(trifluoroacetoxy)iodo]perfluoroalkanes, that can be converted to stable [hydroxy(tosyloxy)iodo]perfluoroalkanes.
A. A. Zagulyaeva, M. S. Yusubov, V. V. Zhdankin, J. Org. Chem., 2010, 75, 2119-2122.
One-pot syntheses of neutral and electron-rich [hydroxy(tosyloxy)iodo]arenes (HTIBs) from iodine and arenes avoid the need for expensive iodine(III) precursors. A large set of HTIBs, including a polyfluorinated analogue, can be obtained from the corresponding aryl iodides under mild conditions, without excess reagents, in high yields.
E. A. Merritt, V. M. T. Carneiro, L. F. Silva Jr., B. Olofsson, J. Org. Chem., 2010, 75, 7416-7419.
Sodium perborate in acetic acid is an effective reagent for the oxidation of aromatic aldehydes to carboxylic acids, iodoarenes to (diacetoxyiodo)arenes, azines to N-oxides, and various sulphur heterocycles to S,S-dioxides. Nitriles undergo smooth oxidative hydration to amides when aqueous methanol is employed as solvent.
A. McKillop, D. Kemp, Tetrahedron, 1989, 45, 3299-3306.
Various [(diacetoxy)iodo]arenes were efficiently prepared by the treatment of iodoarenes with m-chloroperoxybenzoic acid in acetic acid. The great advantage of the present method is the easy preparation and isolation of [(diacetoxy)-iodo]arenes bearing electron-withdrawing groups.
M. Iinuma, K. Moriyama, H. Togo, Synlett, 2012, 23, 2663-2666.
A modified procedure for the direct synthesis of hypervalent [bis(trifluoroacetoxy)iodo]arenes avoids the use of hazardous reagents with the workup being only an aqueous extraction.
T. Keri Page, T. Wirth, Synthesis, 2006, 3080-3084.