Tungstig Acid-Tributyltin Chloride on a Charcoal Catalyst in the Epoxidation of Alkenes with Hydrogen Peroxide

Article abstract of DOI:10.1246/bcsj.58.3193

Several alkenes, such as cyclopentene, cyclohexene, 1-octene, 2-octene, 1-decene, styrene, and 1-methyl-1-cyclohexene, were epoxidized with aqueous (30percent) hydrogen peroxide. n-Bu3SnCl was a good co-catalyst of H2WO4 for selective epoxidation.The conversion was improved by modifying charcoal as the carrier with such alkylating or alkylsilylating agents as N,N-dimethylformamide dibutyl acetal (DMFBA) or N,O-bis(trimethylsilyl)acetamide.Cyclopentene oxide, cyclohexene oxide, and 2-octene oxide were obtained from the corresponding olefins in the good yields of 74, 64, and76percent respectively by using DMFBA-modified charcoal as the support.The epoxidation was first-order with respect to both cyclohexene and H2O2.The apparent activation energy of the epoxidation of cyclohexene was 11.2 kcal/mol.