Iodine compounds, polyvalent organic

A. Varvoglis Polyvalent iodine compounds in organic synthesis [9]... 

Iodosobenzene bistrifluoroacetate is a versatile mild oxidant that has been used to oxidize a broad range of organic compounds, such as alkenes, alkynes, carbonyl compounds, and alcohols Its application in organic synthesis has been summarized m several recent reviews devoted to polyvalent iodine compounds [63, 64, 65]... 

Aryl-, as well as heteroaryliodonium salts, belong to the most common, stable, and well investigated class of polyvalent iodine compounds. The preparation and chemistry of aryliodonium salts was extensively covered in several reviews [5,7,9,10]. Diaryliodonium salts have found synthetic application as arylating reagents in reactions with various organic substrates. 

Iodine differs in many aspects from the other halogens. Because of the large atomic size and the relatively low ionization energy, it can easily form stable polycoordinate, multivalent compounds. Interest in polyvalent organic iodine compounds arises from several factors (a) the similarity of the chemical properties and reactivity of I(III) species to those of Hg(+2), Tl(+3), and Pb(+4), but without the toxic and environmental problems of these heavy metal congeners ... 

A summary of the biological properties of iodonium salts has been provided in a 1996 review [1]. Among the numerous known structural types of polyvalent organic iodine compounds, only aryl- and heteroaryliodonium salts and iodonium ylides have considerable, practically useful biological activity. Table 7.1 provides a brief description of the specific biological activity of several patented iodonium derivatives. 

Stang, P. J. Zhdankin, V. V. Organic Polyvalent Iodine Compounds, Chem. Rev. 1996, 96, 1123-1178. An earlier review. 

GENERAL OVERVIEW OF ORGANIC POLYVALENT IODINE COMPOUNDS... 

Iodine can form organic compounds with oxidation states of +3 and 4-5. The most common stmctural types of organic polyvalent iodine species are represented by structures 1—3, shovm in Figure 1. Structure 1, the iodo-nium ion, formally does not belong to hypervalent species since it has only eight valence electrons on the iodine atom however, in the modem Hterature iodonium salts are commonly treated as the 10-electron hypervalent... 

Figure 1 Typical structural types of organic polyvalent iodine compounds.

Banks, D.F., Organic polyvalent iodine compounds, Chem. Rev., 66, 243,1966. 

Stang, P.J. and Zhdankin, V.V., Organic polyvalent iodine compounds, Chem. Rev., 96,1123,1996. Varvoghs, A., Chemical transformations induced by hypervalent iodine reagents. Tetrahedron, 53, 1179, 1997. 

E. B. Merkushev Organic compounds of polyvalent iodine. Derivatives of iodosobenzene [13]... 

The intention is not to cover the vast halo-organic chemistry in this context, but only organic polyvalent halogen compounds that are actually limited to derivatives with iodine (I), iodine (III), and iodine (V), though evidence for the divalent L2T radical was obtained by the hemolytic cleavage of I-O bonds during thermolysis of tert-butyl-peroxyiodanes7 ... 

Historically, (dichloroiodo)benzene, PhICh, was the first reported organic compound of polyvalent iodine. It was prepared by Willgerodt in 1886 by the reaction of iodobenzene with ICI3 or, preferably, with chlorine... 

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