New selective oxidation of unsymmetrical thiolsulfinates to the corresponding thiolsulfonates with sodium metaperiodate

✍ Scribed by Yong Hae Kirn; Toshikazu Takata; Shigeru Oae

• Book ID: 104242678
• Publisher: Elsevier Science
• Year: 1978
• Tongue: French
• Weight: 248 KB
• Volume: 19
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)91521-7

✦ Synopsis

We have recently reported that oxidations of unsymmetrical thiolsulfinates with peroxy acid 1) or dinitrogen tetraoxide 2) afforded the corresponding symmetrical thiolsulfonates which were undoubtedly derived by the cleavage of sulfur-sulfur bond.

We now have found that both aryl-and alkyl unsymmetrical thiolsulfinates are oxidized selectively with sodium metaperiodate in aqueous media to the corresponding unsymmetrical thiolsulfonates quantitatively. The oxidation was accelerated by addition of a catalytic amount of inorganic or organic acid as well as iodine 3)(Table II).

Since thiolsulfinates are generally unstable and known to disproportionate readily to the corresponding disulfides and thiolsulfonates 4) , only a sporadic studies on the oxidation of thiolsulfinate have been carried out 11215) and showed that all these oxidations involve the cleavage of sulfur-sulfur bond and gave the corresponding thiolsulfonates.

However, surprisingly, with an equimolar amount-of NaI04 all these unsymmetrical thiolsulfinates were selectively oxidized to the corresponding unsymmetrical thiolsulfonates in aqueous solvent such as water-dioxan, acetonitrile or acetic acid under mild conditions(ca. 25O), with no apparent cleavage of sulfur-sulfur bond.