ИСТИНА

Trans-alkene synthesis is complicated task and usually alkene metathesis reactions, cross-coupling and other reactions of forming a new double carbon bond are applied for their synthesis. Selective hydrogenation of substituted alkynes on heterogeneous catalysts is a very attractive alternative to homogeneous methods. However, hydrogenation of internal alkynes on traditional catalysts leads to cis-alkene formation as a main product. There are only a few publications about heterogeneous systems for direct synthesis of trans-alkenes from alkynes. Therefore the development of the efficient catalysts for trans-alkene synthesis remains an important task. A promising approach recently was proposed for such synthesis via selective diphenylacetylene (DPA) hydrogenation to cis-Stilbene (cis-ST) with subsequent isomerisation to trans-Stilbene (trans-ST). In this work the concept was performed with PdxIny intermetallic compounds. Catalytic tests revealed Pd3In7/Al2O3 as the most promising catalytic composition. This sample demonstrates ~ 75.2% yield of trans-ST at 100% conversion of DPA and can be used for the following up-scaling.