Sodium iodide sulfoxides

Spray solution ID For sulfoxides Dissolve 5 g starch and 0.5 g sodium iodide in 100 ml water with wanning. Add 1 ml cone, hydrochloric acid to 10 ml of the solution immediately before use [8]. 

Chemical deoxygenation of sulfoxides to sulfides was carried out by refluxing in aqueous-alcoholic solutions with stannous chloride (yields 62-93%) [186 Procedure 36, p. 214), with titanium trichloride (yields 68-91%) [203], by treatment at room temperature with molybdenum trichloride (prepared by reduction of molybdenyl chloride M0OCI3 with zinc dust in tetrahydrofuran) (yields 78-91%) [216], by heating with vanadium dichloride in aqueous tetrahydrofuran at 100° (yields 74-88%) [216], and by refluxing in aqueous methanol with chromium dichloride (yield 24%) [190], A very impressive method is the conversion of dialkyl and diaryl sulfoxides to sulfides by treatment in acetone solutions for a few minutes with 2.4 equivalents of sodium iodide and 1.2-2.6 equivalents of trifluoroacetic anhydride (isolated yields 90-98%) [655]. 

In the rings containing sulfur, reduction of sulfoxides of phenoxathiin and thianthrene can be performed in excellent yield with the aluminium chloride/sodium iodide or zinc dust/l,4-dibromobutane systems <1996CHEC-II(6)447>. 

ENOL ETHERS Chlorotrimethylsilane-Sodium iodide. Dimethyl sulfoxide. 

The method was used in studies of a fungal heterogalactan.150 The polysaccharide was subjected to successive tritylation, methylation, detritylation, p-toluenesulfonylation, reaction with sodium iodide, and, finally, reaction with sodium p-toluenesulfinate. The product was then treated with sodium methylsulfinyl carbanion in dimethyl sulfoxide, the product remethylated, and the polysaccharide material recovered by gel chromatography. The polymer was hydrolyzed, and the sugars in the hydrolyzate were analyzed, as the alditol acetates, by g.l.c.-m.s.1 The analysis revealed that —60% of the hexose residues that were unsubstituted at C-6 had been eliminated. As the product was still polymeric, it was concluded that these residues had constituted a part of side chains linked to a main chain of (1 — 6)-linked D-galactose residues. 

Diphenylphosphine)lithium, 126 Nickel boride, 197 Samarium(II) iodide, 270 to 1,2-disubstituted compounds B-3-Pinanyl-9-borabicyclo-[3.3.1]nonane, 249 Titanium(III) chloride, 302 of phosphorus compounds Lithium aluminum hydride-Cerium(III) chloride, 159 of sulfoxides and sulfones Sodium iodide-Boron trifluoride ether-ate, 282... 

This strategy involving a Pummerer dehydration of sulfoxide and/or selenoxide is not applicable for preparation of tellurium analogs. The first diheteropentalene bearing the tellurolo[3,4-c]thiophene framework, e.g. 262, has been generated from 259 using tellurium metal in the presence of sodium iodide in DME. Compound 262 appears to be stable in dilute solution for no more than 1-2 h and adds to DMAD across the 4,6-positions in the tellurophene part. The intermediate 263 loses tellurium and collapses to a l,3,5,6-tetramethoxycarbonylbenzo[c]thiophene derivate 264 (Scheme 51) [81],... 

The main methodologies developed until now for enantioselective oxidation of sulfides are effective only in the oxidation of alkyl aryl sulfoxides. Dialkyl sulfoxides on the other hand are generally oxidized with only poor selectivity. In an attempt to solve this problem, Schenk s group69 recently reported a stereoselective oxidation of metal-coordinated thioethers with DMD. The prochiral thioether is first coordinated to a chiral ruthenium complex by reaction with the chloride complexes [CpRu[(S,S)-chiraphos]Cl], 36. Diastereoselective oxygen transfer from DMD produces the corresponding sulfoxides in high yield and selectivity. The chiral sulfoxides 37 are liberated from the complexes by treatment with sodium iodide. Several o.p. aryl methyl sulfoxides have been obtained by this method in moderate to high ee (Scheme 12). 

Trichloro(methyl)silane-Sodium iodide, 11, 553-554. This in situ equivalent of io-dotrimethylsilane is also effective for cleavage of esters and lactones, selective conversion of tertiary and benzylic aleohols into iodides, dehalogenation of a-halo ketones, deoxygenation of sulfoxides, and conversion of dimethyl acetals to carbonyl compounds. ... 

Deoxygenation of sulfoxides and azoxyarenes. This combination is superior to triphenylphosphine-iodine for deoxygenation of sulfoxides to sulfides (70-95% yield) and of azoxy benzenes to azobenzenes ( 90% yield, two examples). The reaction can be promoted by addition of sodium iodide. One advantage is that the by-product, HMPT, is soluble in water and easily removed. 

Aliphatic primary halides—chlorides, bromides, and especially iodides—are converted into aldehydes by treatment with dimethyl sulfoxide [998, 999, 1000] or trimethylaniine oxide [993], The reactivity of alkyl chlorides and bromides is increased by converting them in situ to alkyl iodides by the addition of sodium iodide into the reaction mixtures [999] (equation 188). 

Secondary bromides such as 2-bromobutane and 2-bromooctane are oxidized by dimethyl sulfoxide in the presence of sodium iodide and sodium bicarbonate after 2 h at 115 °C to 2-butanone and 2-octanone in 65 and 56% yields, respectively (equation 190) [999]. 

Drabowicz, J. and Oae, S. (1977) Mild reductions of sulfoxides with trifluoroacetic anhydride/ sodium iodide system. Synthesis, 404-405. 

Sodium dichlorofluoroacetate, 83 Sodium dihydrogen phosphate, 451 Sodium dithionite, 24 Sodium ethoxide, 451-452,467 Sodium hydride, 23, 35, 86, 114, 123, 125, 195, 230, 267, 331, 452-455,465 Sodium hydride-r-Butylchlorite, 455-456 Sodium hydride-Dimethyl sulfoxide, 456 Sodium hydrogen carbonate, 194,406 Sodium hydrosulfite, 24 Sodium 4-hydroxybenzenesulfonate, 504 Sodium hypobromite, 254 Sodium hypochlorite, 456 Sodium iodide, 249-250, 456-457,529 Sodium methoxide, 61, 195, 213, 275, 334, 457-459... 

Dehydrohalogenation Benzyltrimethylammonium mcsitoate. r-Butylamine. Calcium carbonate. j Uidine. Diazabicyclo[3.4.0]nonene-5. N.N-Dimethylaniline (see also Ethoxy-acetylene, preparation). N,N-Dimelhylformamide. Dimethyl sulfoxide-Potassium r-but-oxide. Dimethyl sulfoxide-Sodium bicarbonate. 2,4-Dinitrophenylhydrazine. Ethoxy-carbonylhydrazine. Ethyldicyclohexylamine. Ethyidiisopropylamine. Ion-exchange resins. Lithium. Lithium carbonate. Lithium carbonate-Lithium bromide. Lithium chloride. Methanolic KOH (see DimethylTormamide). N-PhenylmorphoKne. Potassium amide. Potassium r-butoxide. Pyridine. Quinoline. Rhodium-Alumina. Silver oxide. Sodium acetate-Acetonitrile (see Tetrachlorocyclopentadienone, preparation). Sodium amide. Sodium 2-butylcyclohexoxide. Sodium ethoxide (see l-Ethoxybutene-l-yne-3, preparation). Sodium hydride. Sodium iodide in 1,2-dimethoxyethane (see Tetrachlorocyclopentadienone, alternative preparation) Tetraethylammonium chloride. Tri-n-butylamine. Triethylamine. Tri-methyiamine (see Boron trichloride). Trimethyl phosphite. 

Dehalooenation Chromous chloride. Copper powder-Benzoic acid. Dimethyl sulfoxide-NaH. Hydrazine-Palladium. Iron pentacarbonyl. Lithium-l-Butanol-THF. Magnesium-Iodine-Ether. Methyllithium. Sodium acetate. Sodium iodide. Zinc dust. Zinc dust-Ethanol (see Allene, preparation. Hexafluoro-2-butyne, preparation). 

In the ring containing sulfur, sulfoxides of phenoxathiin and thianthrene are reduced to the corresponding sulfides in excellent yields with the aluminum chloride/sodium iodide <88IJC(B)259> or zinc dust/l,4-dibromobutane systems <87CPB435l>. 

Reduction of sulfoxides to sulfides. This reduction can be conducted at 0° by addition of TFAA to an acetone solution of a sulfoxide and sodium iodide. Yields are 90 987o- The reduction involves acylation of the sulfoxide to form an acyloxysulfonium salt, which is converted into a sulfide by iodide anion (equation I). ... 

Deoxygenation of sulfoxides. This reaction can be carried out with triphenyl-phosphine activated by iodine (1 equiv.) in refluxing acetonitrile in 10-60 minutes. Sodium iodide is added to increase the rate. Sulfides are obtained in 70-957, yield. ... 

The chloride (62) thus obtained was resistant to subsequent hydrolysis to the alcohol (47). Therefore, (62) was quantitatively converted into (64) by treatment with sodium iodide in ethyl acetate. For replacement of the iodine in (64) with a hydroxy group, various methods were investigated. These included use of silver perchlorate in aqueous acetone, treatment with silver nitrate or a combination of sodium nitrate and methyl p-toluenesulfonate followed by reduction of the allylic nitrate intermediate with zinc and acetic acid, and application of the Evans method involving sulfoxide rearrangement [29]. A conversion method... 

Difficulties in attachment and lower yields have been encountered with certain specific amino acids such as A -Boc-nitroarginine and N-Boc-proline. Difficulties in linking the first amino acids to the polymer support have also been observed in case of A -Boc-methionine and A -Boc-N -benzylhistidine. For methionine, the difficulty is due to the formation of suifonium derivatives. This was overcome by using methionine, as its sulfoxide, and then reducing the sulfoxide to its thioether by sodium iodide and acetyl chloride in DMF (Norris et aL, 1971). The two last-named amino acids can be linked without any difficulty to the hydroxymethyl polymers and the problem circumvented. 

We applied the McCarthy DAST procedure to the sulfoxides 9a (see Scheme 2) derived by selective oxidation of 2, 3 -di-0-acetyl-5 -S-phenyl-5 -thioadenosine (8a) [ 1 equivalent MCPBA (3-chloroperoxybenzoic acid)/-40 C], but observed minimal conversion to the desired a-fluoro thioethers. The major product was the deoxygenated thioether precursor 8a. Addition of zinc(II) iodide as catalyst resulted in rapid deoxygenation of 9a to give 8a. Facile deoxygenation of sulfoxides to thioethers had been reported with sodium iodide and boron trifluoride etherate, so we investigated other Lewis acid systems that did not contain iodide. 

Y.D. Vankar and C.T. Rao, Sodium iodide/boron trifluoride etherate A mild reagent system for the conversion of allylic and benzylic alcohols into corresponding iodides and sulfoxides into sulEdes, Tetrahedron Utt, 26 2717 (1985). 

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