Synthesis of octyl-ethers of biomass-based glycols through two competitive catalytic routes: Telomerization and etherification

Increasing interest in biomass valorization has triggered a worldwide search for new catalytic routes to transform biomass-based derivatives in transportation fuels and valuable chemicals. It is anticipated that in most cases more than one catalytic pathway can be followed for the synthesis of the desired end products. One such example is the synthesis of octyl-ethers from biomass-based glycols, which can be made either via the telomerization of 1,3-butadiene or the direct etherification of long linear alkenes. For both processes active and selective catalysts have been developed in our groups and their activity and selectivity have been investigated under solvent-free conditions. The telomerization of 1,3-butadiene affords linear octyl-ethers with high yields (up to 80%) with a homogeneous Pd/TOMPP (TOMPP = Tris-(o-methoxyphenyl)phosphine) catalyst. For the direct etherification of glycols with 1-octene H-Beta zeolites were found to be very promising heterogeneous catalysts to produce branched octyl-ethers with yields up to 80%. In this work, a detailed account of the influence of catalyst properties and glycol structure is given and the advantages and disadvantages of both catalytic routes are discussed.