Continuous flow homogeneous catalysis using ionic liquid/supercritical fluid biphasic systems

Catalysis;Hydroformylation;Supercritical fluid extraction;Rhodium catalysts;Silver catalysts

Martins, Tânia Isabel Quintas ; Cole-Hamilton, D. J. (David John) ; Cole-Hamilton, D. J. (David John)

University:University of St Andrews

Department:Chemistry (School of)

关键词: Catalysis;    Hydroformylation;    Supercritical fluid extraction;    Rhodium catalysts;    Silver catalysts;   

Others  :  https://research-repository.st-andrews.ac.uk/bitstream/handle/10023/982/T%c3%a2nia%20Isabel%20Quintas%20Martins%20PhD%20thesis.PDF?sequence=3&isAllowed=y

来源: DR-NTU

【 摘 要 】

Ionic liquid/scCO₂ biphasic systems have been studied as a possible solution tothe main problems concerning homogeneous catalysis reactions such as, theproduct/catalyst separation, the catalyst retention in the reaction medium and theuse of organic solvents. The hydroformylation of long chain alkenes (1-octene)has been carried out as a continuous flow reaction using [OctMIM]Tf₂N (OctMIM= 1-octyl-3-methylimidazolium, Tf = CF₃SO₂) as the reaction solvent and scCO₂as the mobile phase to extract the products. The performance of the rhodiumcomplexes formed with the ionic ligands [PentMIM][TPPTS] (1-pentyl-3-methylimidazolium tri(m-sulfonyl)triphenylphosphine) and [OctMIM][TPPTS](1-octyl-3- methylimidazolium tri(m-sulfonyl)triphenylphosphine) is describedunder different sets of experimental conditions.Continuous flow hydroformylation of 1-octene was also carried out using a SILP(Supported Ionic Liquid Phase) catalyst formed with the TPPTS-based ionicligands named above. The SILP system described in this work has the peculiarityof introducing the “without gases” approach: syn gas was synthesised in situ bythe decomposition of formaldehyde.The performance of both systems is compared in the end.The extension of the continuous flow ionic liquid/scCO₂ biphasic system is shownwith the optimisation of the silver-catalysed heterocyclisation of furans. Acomparison is carried out with a previously developed and optimised continuousflow heterogeneous system.