Oxidations silver trifluoroacetate/iodin

Potassium permanganate. Dimethyl sulfide-Chlorine. Dimethyl sulfoxide. Dimethyl sulfoxide-Chlorine. Dimethylsulf-oxide Sulfur trioxide. Dipyridine chro-mium(VI) oxide. Iodine. Iodine-Potassium iodide. Iodine tris(trifluoroacetate). Iodosobenzene diacetate. Isoamyl nitrite. Lead tetraacetate. Manganese dioxide. Mercuric acetate. Mercuric oxide. Osmium tetroxide—Potassium chlorate. Ozone. Periodic acid. Pertrifluoroacetic acid. Potassium ferrate. Potassium ferricyanide. Potassium nitrosodisulfonate. Ruthenium tetroxide. Selenium dioxide. Silver carbonate. Silver carbonate-Celite. Silver nitrate. Silver oxide. Silver(II) oxide. Sodium hypochlorite. Sulfur trioxide. Thalli-um(III) nitrate. Thallium sulfate. Thalli-um(III) trifluoroacetate. Triphenyl phosphite ozonide. Triphenylphosphine dibromide. Trityl fluoroborate. 

Silver trifluoroacetate. For use in combination with iodine for the 4-iodination of veratrole," the salt is prepared by adding trifluoroacetic acid to a suspension of precipitated silver oxide in water, filtering, and evaporating the filtrate to dryness. Extraetion of the dry salt with ether in a Soxhiet and evaporation of the solvent gives colorless, crystalline material in 88% yield. 

The preferred procedure for iodination of veratrole employs silver trifluoroacetate. An aqueous solution of the salt is prepared from the acid and silver oxide, filtered, and evaporated to dryness the salt is purified by Soxhlet extraction with ether. A solution of iodine in chloroform is added with stirring under reflux to a mixture of... 

SUica gels, 110, 221, 229, 339, 345, 416, 461,505,509 a-Siloxyallylsilanes, 485 Silver acetate, 441-442 Silver carbonate, 441 Silver carbonate-Celite, 441-442 Silver chromate-iodine, 442 Silver cyanide, 442 Silver fluoride, 161 Silver nitrate, 247 Silver(I) oxide, 441, 442-443 Silver tetrafluoroborate, 443-444 Silverll) trifluoroacetate, 444-445 Silver(II) trifluoroacetate, 527 Silylation, 227 Silyl cyclopropanes, 307 Silyl enol ethers, 127, 172, 218, 227, 296, 378, 446, 485, 524-525 Silylvinyl triflates, 410 Simmons-Smith reagent, 172,445 Smiles rearrangement, 243 Sodium, 445... 

Oxidations with iodine silver trifluoroacetate Aldehydes from prim, alcohols s. 16, 321... 

While the silver and zinc salts were effective Lewis acids for these cyclizations, Kikugawa and coworkers reported that the alkoxynitrenium ions could be generated directly from hydroxamic esters (4) using hypervalent iodine oxidants such as hydroxy(tosyloxy) iodobenzene (HUB) and phenyliodine(lll)bis(trifluoroacetate) (PIFA) . Presumably, with such reagents the reactions proceed through A-(oxoiodobenzene) intermediates (54), which can themselves be regarded as anomeric hydroxamic esters and sources of alkoxynitrenium ions (55) (Scheme 11). 

Reagents for oxidation 5,5 -dithio-hw-(2-nitrobenzoic acid) (DTNB, Ellman reagent)", silver triflate (AgOTf)", thallium trifluoroacetate (Tl(tfa)3), iodine, and guanidine HCT (Fluka or Sigma-Aldrich). 

E22b, Section 6.1.1.2.1)j l Por stepwise regioselective disulfide formation, the iodine-mediated oxidative deprotection of a pair of Cys(Trt) residues is a widely applied procedure (see Vol.E22b, Sections 6.1.2-6.1.4). Finally, 5-trityl groups are efficiently cleaved with metal ions such as mercury(II) and silver(I),t 51 or with thalhum(III) trifluoroacetate.P ... 

OXIDATION, REAGENTS Acetyl nitrate. Bis(tri-n-butyltin)oxide. Bromine-Hexameth-ylphosphoric triamide. f-Butyl perbenzoate. Ceric ammonium nitrate. N-chlorosuc-cinimide-Dimethyl sulfide. Chromic add. Chromic anhydride. Chromic anhydride-Acetic anhydride. Chromic anhydride-Hexamethylphosphoric triamide. 2,3-Dichloro-5,6-dicyano-l,4-benzoquinone. Dimethyl sulfoxide. Dimethyl sulfoxide-Trifluoro-acetic anhydride. Diphenylseleninlc anhydride. Iodine tris(trifluoroacetate). Lead tetraacetate. N-Methylmorpholine -N-oxide. p-NitrobenzenesulfonyI peroxide. Oxygen, singlet. Palladlumfll) chloride. Peroxybcnzimidic acid. Phenylseleninyl chloride. N-Phenyl-l,2,4-triazoline-3,5-dione. Potassium chromate. Potassium superoxide. Pyri-dinium chlorodiromate. Salcomine. Silver carbonate-Celite. Sodium hypochlorite. Sulfuryl chloridc-Silica gel. Thallium(III) acetate. ThaUium(III) nitrate. Triphenyl phosphite ozonide. Trltyl tetrafluoroborate. Uranium hexafluoride. 

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