Ru-Triphos complex as catalyst for the selective hydrogenation of biobased carboxylic acids

National @ CDFA+WHN:LCH:NESInternational audienceBiorefinery is an alternative of petroleum refinery that integrates biomass conversion processes to produce fuels, power, heat, and value-added chemicals. Succinic acid is one of the building block molecules issued from biomass identified by these biorefineries, becaude it can be converted to products with economic interest for industries [1]. Despite numerous papers and patents regarding heterogeneous catalysts for the reduction of esters and acids to alcohols [2,3], a minor effort has been devoted to the application of the homogeneous hydrogenation which has involved mostly soluble ruthenium complexes.This research focuses on the hydrogenation of succinic acid, chosen as a model molecule for carboxylic acids, by active homogeneous catalyst based on a Ru - Triphos complex [4-6], using biosourced ethanol as solvent. The compounds that can be formed from the hydrogenation af succinic acid are Tetrahydrofuran (THF), γ-butyrolactone (GBL), and 1,4-Butanediol (BDO). We focus on this diol because it is commonly used in polymer synthesis. In order to obtain a better selectivity and maximum yield of 1,4-BDO, different reaction parameters were optimized and better results were obtained at 60 bar H2 and 150°C, leading to a complete succinic acid conversion and 1,4-BDO yields up to 90%. We also isolated a Ru complex from the reaction media and suitable crystals allowed an XR diffraction analysis that is in accordance with literature proposed structures. We are actually working on the hydrogenation of other biosourced acids