Sulfoxide-Iodine

Quinkert, G. Duemer, G. Kleiner, E. Adam, F. Haupt, E. Liehfritz, 

Joseph P. Marino David R Holub University of Michigan, Ann Arbor, MI, USA 

Solubility DMSO sol H2O, alcohol, acetone, THF, CH2CI2.12 sol ether, CHCI3, CS2, aq soln HI. 

Form Supplied in DMSO is a colorless liquid widely available, including anhydrous grades of 99%+ DMSO packed under N2.12 is a widely available crystalline solid. 

Preparative Methods the actual reagent may differ from one reaction to another, and the specific procedures also differ. 

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Dimethyl sulfoxide-iodine, 190-191 Dimethyl sulfoxide-Methanesulfonic anhydride, 191... 

DIKETONES Dimethyl sulfoxide-iodine. Methyl 2-nitrophenyl disulfide. 

Dimethyl Sulfoxide-Iodine, 233 Dimethyl Sulfoxide-Methanesulfonlc Anhydride, 234 Dimethyl Sulfoxide-Phosphorus Pentoxlde, 234 Dimethyl Sulfoxide-Silver Tetrafluoroborate, 235... 

Pyrrole, 4-ethynyl-2-formyl-3-methyl-synthesis, 4, 222 Pyrrole, formyl-oxidation, 4, 289 reactions, 4, 292 with sulfoxides, 4, 293 synthesis, 4, 223, 274, 287 Pyrrole, 1-formyl-barrier to rotation, 4, 193 Pyrrole, 2-formyl-benzoylation, 4, 220 conformation, 2, 107 4, 193 diacetoxythallium derivative iodination, 4, 216 dipole moment, 4, 194 ketals, 4, 290 protonation, 4, 47 reactions... 

In a similar reaction, iodine fluonde also can be removed from perfluorobutyl-, perfluorohexyl-, and perfluorooctyl iodide by using zinc-copper couple in dimethyl sulfoxide or dimethylformamide [71]... 

Halogenation of 106 with triphenylphosphine, iodine, and imidazole provided the iodo derivative 109. On treatment with lithium aluminum hydride, 109 was converted into two endocyclic alkenes, 110 and di-O-isopro-pylidenecyclohexanetetrol, in the ratio of 2 1. Oxidation of 110 with dimethyl sulfoxide - oxalyl chloride afforded the enone 111.1,4-Addition of ethyl 2-lithio-l,3-dithiane-2-carboxylate provided compound 112. Reduction of 112 with lithium aluminum hydride, and shortening of the side-chain, gave compound 113, which was converted into 114 by deprotection. ... 

Pure dimethyltriazanium chloride decomposes at 133 to 134° (the checker reports 135 to 136°). The salt is very hygroscopic and should be stored in a desiccator. It is readily soluble in water, methanol, ethanol, and dimethyl sulfoxide. An aqueous solution is stable at room temperature. Free iodine is liberated from an acidic iodide solution, and this reaction makes it possible to determine the triazanium content.3... 

Molecular iodine has also been demonstrated to adivate certain mannosyl sulfoxides albeit over extended periods of time and at higher temperatures. Mannosyl iodides may be involved as intermediates here, but O-iodyl mannosyl sulfonium salts have also been discussed [334]. The yield and selectivity of these readions vary with resped to the potency of the iodonium ion source, IBr yielding much less... 

Asymmetric oxidation of sulfides to sulfoxides occurs in the presence of chiral catalysts. It was found (53) that oxidation of benzyl methyl sulfide with iodine suspended in (i )-2-methyl-2-phenylsuccinate 33 buffer gives optically active benzyl methyl sulfoxide 34 having 6.35% optical purity. Much higher asymmetric... 

The reduction of (2,3)-q - and (2,3)-jS-methylenepenam j6-sulfoxides to the corresponding sulfides using potassium iodide and trifluoroacetic anhydride (TFAA) is found to be much faster than for bicyclic jS-lactam jS-sulfoxides.- In the proposed mechanism, initial attack of the sulfoxide oxygen on TFAA is followed by rate-limiting, nucleophilic displacement of trifluoroacetate by iodide ion nucleophilic attack of iodide on the iodine atom then yields the sulfide and iodine. The rate enhancement is accounted for by the stabilization of the transition state in the rate-limiting step by interaction of the p-like orbital of sulfur and the cyclopropane a orbital. 

Disulfide formation using a mixture of chlorosilanes and sulfoxides is a novel oxidation procedure developed independently by Akaji et al. 94-95 and Koide et al. 96 The reagents oxidatively cleave almost all types of S-protecting groups including those which are not oxidatively cleaved by iodine. Therefore, this procedure offers an additional dimension to the strategies of regioselective multiple-disulfide formation (see Section 6.1.4.2). 

Much of the experience gained in the field of solution-phase oxidative deprotection of cysteine peptides can be applied to solid-phase chemistry. For this purpose the iodine, thallium(III), and chlorosilane/sulfoxide procedures have been usually employed,163 107-1121 generally, the results obtained with the thallium(III) reagent are better than with iodine. 

Disulfide Formation by a Combination of Iodine and Chlorosilane/Sulfoxide... 

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