Selective addition of isobutene over ZrSiO4/SiO2-SO3H: Hydroacetoxylation versus dimerization

Abstract

The acid-catalyzed Markovnikov addition of isobutene is affected by the concomitant isobutene oligomerization. Herein, a solid acid catalyst consisting of the sulfonated silica modified with crystalline ZrSiO4 was prepared, and the ZrSiO4/SiO2-SO3H catalyst went beyond conventional acid catalysts in the hydroacetoxylation of isobutene. The structure of the catalyst was well-characterized, and the role of ZrSiO4 in suppressing the dimerization of isobutene was discussed in terms of both kinetic study and in-situ DRIFT analysis. Moreover, this catalyst also showed general applicability for a broad substrate scope, further highlighting the necessity of ZrSiO4 in the solid acid catalyst.

Keywords

• Selective hydroacetoxylation
• Isobutene dimerization
• ZrSiO4
• tert-butyl ester