Iodine trivalent, compounds

This trivalent iodine compound is obtained in about 90% yield by reaction of C H5I(OAc)2 with toluenesulfonic acid (2 equiv.) in CH,CN. ... 

Phenylbenzoic acid is converted into benzo[c]coumarin in the Su z system, that is irradiation when mixed with trivalent iodine compounds and iodine the 2-iodo derivative may also be formed <99JCS(P1)1713>. 

Iodobenzene and some Related Compounds.—Aromatic iodo-compounds containing iodine in the nucleus unite with two atoms of chlorine to form iodochlorides (Preparation 469), the iodine becoming trivalent. Caustic soda converts the latter into iodoso-compounds, oxygen replacing the two chlorine atoms (Preparation 465.)... 

Togo, H., Aoki, M., and Yokohama, M. (1993) Reductive addition to electron-deficient olefins with trivalent iodine compounds. Tetrahedron, 49, 8241-8256. 

Trivalent iodine compounds can be divided into the following categories (1) with one carbon-iodine bond, such as in iodo salts, RIX2, and iodoso compounds, RIO (2) with two carbon-iodine bonds on the same iodine, such as RRTX and (3) with three carbon-iodine bonds on the same iodine, such as Phsl. 

The reaction of aliphatic carboxylate esters or ethers with carbon monoxide in the presence of nickel or a nickel derivative, iodine or an iodine compound, and an organic trivalent Group VA element compound and DBU under pressure gave carboxylic acid anhydrides (79GEP2844371). 

Two oxidants essentially dominate these oxidations lead tetraacetate in organic solvents and periodic acid in aqueous media. On occasion, other oxidation reagents cause the cleavage of vicinal diols ceric ammonium nitrate [424], sodium bismuthate [482, 483], chromium trioxide [482, 555], potassium dichromate with perchloric acid [949], manganese dioxide [817], and trivalent [779, 789] or pentavalent [798] iodine compounds. 

V-chloro-1,2,4-triazole 43 reacts with methyl iodide in the same manner. Formation of iodine and a mixture of /V-unsubstituted 1,2,4-triazoles, isomeric /V-alkyltriazoles, /V-iodotriazolcs, 1,4-dimethyltriazolium salts, and the products of their further transformations is observed (94ZOR1398 95ZOR113, 95ZOR1227). It is proposed that, similarly to N-halobenzotri-azoles, formation of an intermediate trivalent iodine compound and its subsequent cleavage to the reaction products takes place (Scheme 118). 

Radical alkylation and carbamoylation of 4-cyanopyridine (54) have been reported. (54) has been alkylated with carboxylic acids, using trivalent iodine compounds as oxidant, to give (65) (Scheme 32) (93JCS(P1)2417>. (54)... 

Hypervalent iodine compounds can serve as effective oxidants of trivalent phosphorus compounds. In particular, various organic phosphines are selectively oxidized by iodosylbenzene to the respective phosphine oxides in quantitative yield [542]. 

Given the variety of iodine valence states in organoiodine compounds, the A nomenclature (see Section 1.26) will prove useful for our discussion. Dichloroiodobenzene is thus a A -iodane, the superscript being essentially the valence of the atom in question. As shown below, a number of other A -iodanes such as iodobenzene diacetate are also readily accessible from iodobenzene the pentavalent iodine compound iodoxybenzene is shown below in a different color to distinguish it from the other trivalent compounds. 

Togo, H., Aoki, M., and Yokoyama, M., Facile radical decarboxylative alkylation of heteroaromatic bases using carboxylic acids and trivalent iodine compounds, Tetrahedron Lett., 32, 6559, 1991. Togo, H., Aoki, M., and Yokoyama, M., Alkylation of aromatic heterocycles with oxalic acid monoalkyl esters in the presence of trivalent iodine compounds, Chem. Lett., 1691,1991. Vismara, E., Torri, G., Pastori, N., and Marchiandi, M., A new approach to the stereoselective synthesis of C-nucleosides via homolytic heteroaromatic substitution. Tetrahedron Lett., 33, 7575, 1992. 

Togo, H., Hoshina, Y, Nogami, G., and Yokoyama, M., Radical reactions with trivalent iodine compounds, Yuki Gosei Kagaku Kyokaishi, 55, 90,1997. 

Arsenious oxide, trivalent antimony (73), sulfurous acid (74), hydrogen sulfide (75), stannous ion, and thiocianate (76) have been recommended for the titration of iodine. However, none of these appears to have a greater sensitivity for the deterrnination of minute quantities of iodine than thiosulfate. Organic compounds such as formaldehyde (77), chloral hydrate (78), aldoses (79), acetone (70,80), and hydroquinone have also been suggested for this purpose. 

Trimethylarsine gives a 98% yield of trimethylarsine difluoride when treated with xenon difluoride [102] in fluorotrichloromelhane. and tnsfpentafluorophen-yl)arsine gives a 94% yield of tris(pentafluornphenyl)arsme difluoride after reaction with dilute fluorine in fluorotnchloromethane at 0 C [106] Other trivalent arsenic compounds have also been fluorinated with xenon difluoride [103] In addition, arsines have been oxidatively fluorinated by iodine pentafluoride [107] or electrochemically in 26-34% yield [108]... 

In the work reported here, which was directed toward the attainment of an isotopic enrichment of the trivalent actinide and lanthanide elements, the problem was compounded by the fact that these elements do not readily form appropriate compounds, like iodine in ethyl iodide. They do form some stable organic chelates, and, indeed, it is possible to obtain a Szilard-Chalmers reaction with such compounds. However, their radiation damage resistance does not appear adequate to permit useful production of an isotope like 247Cm, which requires a thermal neutron exposure ap-... 

The first few pentacoordinate cationic silicon complexes (153-155) were discussed in an earlier review2. The first two were described as trivalent silicenium ions stabilized by mtermolecularcoordination183 184, while 155 is an intramolecular silicenium ion21a. Since then, a few other compounds were reported. Oxidation of the dihydrido-hexacoordinate chelate 156 by the addition of excess iodine produced 157185. The X-ray structure of 157 showed a slightly distorted TBP for the cation, with a well separated (Si—I distance 5.036 A) I8 2 anion for every two cations. The nitrogens are in the apical positions, and both Si-N distances (2.08 and 2.06 A) are longer than covalent bonds but well within the coordination distance. 

The combination of triphenylphosphine with esters of trihaloacetic acids provides a reagent system for the stereo- and regio-selective conversion of alcohols into alkyl halides.The bromine-triphenylphosphine adduct has been used at low temperatures (-50 C in dichloromethane) for the removal of the tetrahydropyranyl protecting group from tetrahydropyranyl ethers derived from secondary and tertiary alcohols.The reactions of tertiary phosphines (and other trivalent phosphorus compounds) with iodine in aprotic solvents have received further study, a range of species being identified.The first reported study of the reactions of trivalent phosphorus compounds with monopositive astatine has led to the identification of stable complexes with triphenylphosphine, trioctylphosphine, and triethylphosphite. 

Several oxidants are derivatives of iodoaromatic compounds containing trivalent and pentavalent iodine. 

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