Potassium permanganate sulfoxides

With oxidative reagents of a nucleophilic nature such as sodium and potassium permanganate, sulfoxides react faster than sulfides and a chemoselective oxidation of a sulfoxide in preference to that of a sulfide is available [77-79]. 

Ueno and coworkers49 have developed a procedure for the synthesis of chiral sulfinic acids. Treatment of (R)-( + )-23 with disulfide 24 and tributylphosphine in THF gave (S)-( — )-25. Compound 25 was oxidized with potassium permanganate to the sulfone, which was then reduced to the sulfinic acid, (S)-( — )-26, by treatment with sodium borohydride. Conversion of 26 or an analog to an ester would lead to diastereomers. If these epimers could be separated, then they would offer a path to homochiral sulfoxides with stereogenic carbon and sulfur atoms. 

Solvents Water (purified water or water-for-injection grade) toluene, methanol, ethanol, ether, acetate, dimethyl sulfoxide, tetrahydrofuran, hexane, cyclohexane, dichloromethane, acetonitrile, acetone Oxidizing Agents Hydrogen peroxide, chromic acid, potassium permanganate, manganese dioxide, ozone... 

Thiazines can be oxidized at the sulfur atom to give sulfoxides and eventually sulfones. Generally speaking, however, this is not a good approach to these structures as there are inherent problems of non-selectivity and over-oxidation. Air oxidation is sufficient to convert the 1,3-benzothiazine (24 R = alkoxy) into the 1-oxide (25 n = 1), whereas potassium permanganate yields the 1,1-dioxide (25 n = 2). In the case of the unsubstituted compound (24 R = H) the sulfur atom is less reactive and oxidation affords the l,3-benzothiazin-4-one (26) (77ACH(92)317). 

Butyl hypochlorite, 55 of phenols to quinones Benzoyl /-butyl nitroxide, 28 2,3-Dichloro-5,6-dicyano-l, 4-benzoqui-none, 104 Periodic acid, 238 of phosphorus compounds Dimethyldioxirane, 120 of selenium compounds Potassium permanganate, 258 of sulfides to sulfoxides and sulfones /-Butyl hydroperoxide-Dialkyl tar-trate-Titanium(IV) isopropoxide, 51 ra-Chloroperbenzoic acid, 76, 112 Dimethyldioxirane, 120 of thiols to sulfur compounds Trimethylsilyl chlorochromate, 327... 

In the case of 2,3-disubstituted dihydrobenzo-TAs, oxidation by potassium permanganate results in a mixture of sulfoxides and sulfones (69USP3455915). Only sulfones were obtained by potassium permanganate oxidation (63JOC2160 70JHC1007). 

The popularity of the Nef reaction is due in part to the ready availability of nitro compounds. Primary and secondary halides react with sodium nitrite in dimeAyl sulfoxide (DMSO) or dimethylform-amide (DMF) to give useful yields of nitro compounds. Primary amines can be oxidized to nitro compounds with potassium permanganate, m-chloroperbenzoic acitP or ozone. Chlorination of oximes with hypochlorous acid and reduction with magnesium, zinc or hydrogen/lpalladium gives secondary nitro compounds. Stabilized carbanions can be nitrated by treauitent with a nitrate ester, and enol acetates are nitrated by acetyl nitrate to give nitro ketones. ... 

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