Tetrabutylammonium peroxydisulfate

Tetrabutylammonium peroxydisulfate-mediated oxidative cycloaddition was recently discovered to be a convenient method for the realization of fused acetal derivatives. It is believed that the reactive intermediate is the cyclic enol ethers of the 1,3-diketones. An example is presented below <00S1091>. 

A convenient approach to the synthesis of fused furofuran derivatives is provided by the tetrabutylammonium peroxydisulfate-mediated oxidative cycloaddition of 1,3-dicarbonyl compounds to cyclic enol ethers. In the presence of a base such as potassium acetate in acetonitrile, several fused acetal derivatives of type 39 have been prepared in 82-90% yield (Equation 62) <200081091 >. 

Epoxidation. 30% Hydrogen peroxide proves effective in epoxidizing unactivated alkenes in the presence of Af.N -dicyclohexylcarbodiimide. Epoxidation of enones is mediated by tetrabutylammonium peroxydisulfate. ... 

Tetrabutylammonium peroxydisulfate, I2, 25-50 C, CH3CN, H2O, 0.5-4 h, 81-95% yield. When tetrabutylammonium peroxydisulfate is used alone the allyl group is oxidized to an ester which is then cleaved with MeONa/ MeOH. ... 

Epoxidation. Conjugated carbonyl compounds are epoxidized with stoichiometric H2O2 and NaOH while employing tetrabutylammonium peroxydisulfate as catalysC... 

Kim and colleagues studied the use of the one-electron oxidant tetrabutylammonium peroxydisulfate as initiator in conjunction with formate as reductant. This protocol was designed to be more appropriate for bulk chemical deoxygenations, as the use of AIBN or peroxides can be dangerous on large scale. Tetrabutylammonium peroxydisulfate is soluble in organic solvents such as acetonitrile, DMF and chlorinated solvents. 

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