Carboxylic acids Hydrogen peroxide-Sodium tungstate

As with percarboxylic acids, hydrogen peroxide usually requires metal activation.151-154 Peroxo complexes of d° transition metals can often be used to cleave olefins. Tungstic acid cleaves olefins to the carboxylic acid using 35% m/m hydrogen peroxide.154 Sodium tungstate has also been reported to... 

Tetrahydrobenzyl alcohol (( )3-cyclohexenene-l-methanol) and 30% aqueous hydrogen peroxide were purchased from Fluka, AG. 3-Cyclohexene-1-carboxylic acid and cis-4-cyclohexene-l,2-dicarboxylic acid were used as purchased from Lancaster Chemical Co. Methyl iodide, acetic anhydride, Oxone (potassium peroxymonosulfate), Aliquot 336 (methyl tri-n-octylammonium chloride), sodium tungstate dihydrate and N,N-dimethylaminopyridine (DMAP) were purchased from Aldrich Chemical Co. and used as received. 3,4-Epoxycyclohexylmethyl 3, 4 -epoxycyclohexane carboxylate (ERL 4221) and 4-vinylcyclohexene dioxide were used as purchased from the Union Carbide Corp. (4-n-Octyloxyphenyl)phenyliodonium hexafluoroantimonate used as a photoinitiator was prepared by a procedure described previously (4). 

A number of primary alcohols can be oxidised to the corresponding carboxylic acid (Scheme 6) using sodium tungstate as catalyst in 30% aqueous hydrogen peroxide. 

---