Selective Oxidation of Oximes to their Corresponding Carbonyl Compounds by Sym-Collidinium Chlorochromate (S-COCC) as a Efficient and Novel Oxidizing Agent and Theoretical Study of NMR Shielding Tensors and Thermochemical Parameters

Sym- collidinium chlorochromate (S-COCC), is a new, rapid and useful reagent for the oxidative deprotection of oximes to the corresponding carbonyl compounds. The interesting feature of this catalytic system is that oximes which have conjugated C=C bonds, the C=N bond will selectively convert to the relevant C=O bond. The reactions proceed under room temperature, ethylacetate as solvent and in the presence of catalytic amount of aluminum chloride to offer the products in excellent yields. Furthermore, in this study, it is indicated that both oximes with electron-withdrawing groups and oximes with electron-donating groups produced carbonyl compounds in good yields. In this protocol, the deprotection of oximes is less dependent on the electronic property of substrates. A theoretical study of NMR shielding tensors and thermochemical parameters of substrates has also been carried out.