Alcohols, reaction with tetrapropylammonium

Good yields of oi-aminothioethers were obtained on electroreduction of, ]J-disubstituted thioamides in acetonitrile containing tetrapropylammonium perchlorate and an alkylating agent. 2-Aminothioethers and 2-aminoethers were obtained from N-phthalimi-doaziridines by reaction with thiols and alcohols respectively, followed by reduction of the resultant B-hydrazino-thioethers and -ethers. 

The oxidation of alcohols with (l,l-dimethylethyl)benzene-sulfenamide is extremely mild and many sensitive functional groups such as epoxides and alkenes are tolerated hy the reaction conditions (eq 5). In the case of alcohol 1, oxidation with tetrapropylammonium perruthenate (TPAP) resulted in only 58% yield and Swern oxidation was unsuccessful. Epimerizable aldehydes such as the protected phenylglycinol 2 do not undergo racemization when oxidized (eq 6). ... 

There are problems associated with the expensive disposal of toxic waste from metal-based oxidations of alcohols. Thus, the focus has been largely on catalytic reactions as typified by Ley and Griffith s tetrapropylammonium perruthenate oxidant (section 7.1.6). Completely metal-free oxidations have much potential for environment-friendly oxidations, particularly if the reagent can be recovered and recycled. The most common metal-free oxidation of alcohols are TEMPO/oxone or TEMPO/N-chlorosuccinimide oxidation, Dess-Martin periodane oxidation (section 7.1.5) and Swern oxidation (section 7.1.4) and its several variants. 

Another ruthenium-catalyzed oxidation uses tetrapropylammonium permthenate (TRAP) [24]. Being a ruthenium(VII) oxide, the permthenate ion is a less powerful oxidant than rutheni-um(VIII) oxide and more functional groups are stable to the oxidation conditions, including alkenes, alkynes, amines, amides, benzyl, trityl and silyl ethers [24]. However, alcohols and lactols still undergo oxidations in high yield with W-methyl-morpholine A-oxide (NMO) as the stoichiometric oxidant. The reactions are usually carried out in dichloromethane, acetonitrile, or mixtures of both in the presence of molecular sieves [24]. 

F.i. Tetrapropylammonium Perruthenate-Ley Oxidation. Ruthenium derivatives have been used for oxidation reactions. A particularly useful one is TPAP, introduced by Ley for the oxidation of alcohols and called Ley oxidation. 1 2 a very mild oxidizing agent that is compatible with many sensitive... 

Solandelactones A, B, E, and F have been synthesized by White et al., in which the diene side chain was installed using a Nozaki-Hiyama-Kishi reaction. Aldehydes 48 and 49 were prepared by tetrapropylammonium perruthenate oxidation of the corresponding alcohols and were immediately treated with CrCla and NiCl2 to afford the natural products solandelactone A, B, E, and F (Scheme 12.36). ... 

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