Air oxidation of olefins using titanium substituted heteropoly anions

Abstract

Air oxidation of styrene and cyclohexene has been studied in the presence of isobutyraldehyde as reductant using heteropoly an ion catalys ts such as K₅[PW₁₁TiO₄₀], K₇[PW₁₀Ti₂O₄₀], K₂[Bu₄N]₅ [PW₁₀Ti₂O₄₀], Na_2.25 [(CH₃)₂(C₆H₅ )(C₆H₅,CH₂)N]_4.75

[PW₁₀Ti₂O₄₀ and K₇[PW₁₀Ti₂O₄₀] supported on silica (10% by wt.). The major product of oxidation of styrene is styrene oxide while that for cyclohexene is the corresponding oxide. The maximum molar conversion for styrene is 81 % with 83% selectivity for the oxide: for cyclohexene, these values are 49 and 93% respectively.