Monomolecular mechanisms of isobutanol conversion to butenes catalyzed by acidic zeolites: Alcohol isomerization as a key to the production of linear butenes

Density functional theory calculations are performed to explore the mechanisms of poorly understood monomolecular conversions isobutanol butenes, belonging an important class transformations biobased molecules into chemicals. Except for lowest reaction temperatures (<405 K), at which a conventional mechanism via alkoxide intermediates dominates, alkenes formation proceeds newly explored routes involving alcohol isomerization followed by dehydration according E2 mechanism. The carbenium ion deprotonation in latter step is facilitated water molecule created during reaction. In contrast, found be unfavorable all conditions. A favourable unconventional linear from discovered, and combined single step. Our work represents key unraveling why butenes formed some zeolites when used as reagent.