Iodosobenzene is prepared from iodobenzene.[3] It is prepared by first oxidizing iodobenzene by peracetic acid. Hydrolysis of resulting diacetate affords "PhIO":[4]
C6H5I + CH3CO3H + CH3CO2H → C6H5I(O2CCH3)2 + H2O
C6H5I(O2CCH3)2 + H2O → C6H5IO + 2 CH3CO2H
The structure of iodosobenzene has been verified by crystallographically.[5] Related derivatives are also oligomeric.[6] Its low solubility in most solvents and vibrational spectroscopy indicate that it is not molecular, but is polymeric, consisting of –I–O–I–O– chains.[7] The related diacetate, C6H5I(O2CCH3)2, illustrates the ability of iodine(III) to adopt a T-shaped geometry without multiple bonds.[8]
Theoretical studies show that the bonding between the iodine and oxygen atoms in iodosobenzene represents a single dative I-O sigma bond, confirming the absence of the double I=O bond.[9]
A monomeric derivative iodosylbenzene is known in the form of 2-(tert-butylsulfonyl)iodosylbenzene, a yellow solid. C-I-O angle is 94.78°, C-I and I-O distances are 2.128 and 1.848 Å.[10]
Applications
Iodosobenzene has no commercial uses, but in the laboratory it is employed as an "oxo-transfer reagent." It epoxidizes certain alkenes and converts some metal complexes into the corresponding oxo derivatives. Although it is an oxidant, it is also mildly nucleophilic. These oxo-transfer reactions operate by the intermediacy of adducts PhI=O→M, which release PhI.[11]
^Richter, Helen W.; Koser, Gerald F.; Incarvito, Christopher D.; Rheingold, Arnold L. (2007). "Preparation and Structure of a Solid-State Hypervalent-Iodine Polymer Containing Iodine and Oxygen Atoms in Fused 12-Atom Hexagonal Rings". Inorganic Chemistry. 46 (14): 5555–5561. doi:10.1021/ic0701716. PMID17569525.
^C. J. Carmalt, Claire J.; J. G. Crossley; J. G. Knight; P. Lightfoot; A. Martín; M. P. Muldowney; N. C. Norman; A. G. Orpen (1994). "An examination of the structures of iodosylbenzene (PhIO) and the related imido compound, PhINSO2-4-Me-C6H4, by X-ray powder diffraction and EXAFS (extended X-ray absorption fine structure) spectroscopy". J. Chem. Soc., Chem. Commun. (20): 2367–2368. doi:10.1039/C39940002367.
^Ivanov, A.; Popov, A.; Boldyrev, A.; Zhdankin, V. (2014). "The I=X (X = O,N,C) Double Bond in Hypervalent Iodine Compounds: Is it Real?". Angew. Chem. Int. Ed. 53 (36): 9617–9621. doi:10.1002/anie.201405142. PMID25045143.
^MacIkenas, Dainius; Skrzypczak-Jankun, Ewa; Protasiewicz, John D. (2000). "Redirecting Secondary Bonds to Control Molecular and Crystal Properties of an Iodosyl- and an Iodylbenzene". Angewandte Chemie International Edition. 39 (11): 2007–2010. doi:10.1002/1521-3773(20000602)39:11<2007::AID-ANIE2007>3.0.CO;2-Z. PMID10941012.
^Lennartson, Anders; McKenzie, Christine J. (2012). "An Iron(III) Iodosylbenzene Complex: A Masked Non-Heme FeVO". Angewandte Chemie International Edition. 51 (27): 6767–6770. doi:10.1002/anie.201202487. PMID22639404.