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dc.contributor.authorHopmann, Kathrin Helen
dc.contributor.authorFrediani, Luca
dc.contributor.authorBayer, Annette
dc.date.accessioned2016-09-13T12:48:14Z
dc.date.available2016-09-13T12:48:14Z
dc.date.issued2014-05-27
dc.description.abstractRecent experimental studies of iridium-phosphinooxazoline-mediated alkene hydrogenation indicated two dihydride species as resting states, with the minor isomer assumed to give rise to the major product enantiomer [Gruber and Pfaltz, Angew. Chem. Int. Ed. 2014, 53, 1896]. B3LYP-D2 calculations confirm the two dihydride intermediates as resting states but show that these species do not give rise to the lowest-lying hydrogenation barriers. Instead, both species prefer to isomerize to different intermediates prior to hydrogenation. The computed enantiomeric excess (ee) at 298 K is in excellent agreement with experiment. The calculations further show an increased barrier for isomerization between the dihydride species at lower temperature. Numerical simulations of the overall reaction kinetics indicate that this can explain the reduced enantioselectivity observed experimentally at 233 K. Analysis of the selectivity-determining interactions identifies strong C-H/π interactions between the oxazoline substituents and the alkene. On the basis of the insights obtained, a rational redesign of the catalyst is suggested, resulting in an improved ee in silico. Additional benchmark studies on different experimental barriers and reaction energies for iridium complexes confirm the suitability of the employed computational protocol.en_US
dc.identifier.cristinIDFRIDAID 1134377
dc.identifier.issn0276-7333
dc.identifier.urihttps://hdl.handle.net/10037/9680
dc.identifier.urnURN:NBN:no-uit_munin_9204
dc.language.isoengen_US
dc.rights.accessRightsopenAccess
dc.subjectVDP::Matematikk og Naturvitenskap: 400::Kjemi: 440en_US
dc.subjectVDP::Mathematics and natural science: 400::Chemistry: 440en_US
dc.titleIridium-PHOX-mediated alkene hydrogenation: Isomerisation influences the stereochemical outcomeen_US
dc.typeJournal articleen_US
dc.typeTidsskriftartikkelen_US
dc.typePeer revieweden_US


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