Sustainable Preparation of Campholenic Aldehyde from Biorenewable Α-Pinene Via Efficient Epoxidation and Isomerization Using Recoverable Catalysts

Abstract

As a highly valuable fine chemical, economical and environmentally friendly productionof campholenic aldehyde is of great significance. In this work, using α-pinene asbiorenewable feedstock, campholenic aldehyde has been synthesized via epoxidationand isomerization. Using the polyoxometalate-based catalyst, the highly efficient α-pinene epoxidation (selectivity: 96.9%) can be achieved under the conditions of lowerH2O2 dosage, lower temperature and shorter reaction time. In the isomerization of theα-pinene oxide catalyzed by cheap/readily available MCM-22, high conversion (99.3%)and considerable selectivity (82.6%) can be obtained. Particularly, two catalysts can befacially recovered with good cycling stabilities. Furthermore, continuous reaction on theisomerization step was executed. To our delight, the shorter reaction time, less solventconsumption and lower temperature point to the high possibility of industrialproduction. This work presents the efficient synthesis of campholenic aldehydefrom biorenewable α-pinene using recoverable catalysts, which paves a broad way forits industrial applications.

Keywords: Campholenic aldehyde, α-Pinene, Epoxidation, Isomerization, Phase transfer catalysts, MCM-22