Theoretical investigation on the mechanism of ferrocenecarboxaldehyde-catalyzed direct β-alkylation of 1-phenylethanol with benzyl alcohol

Abstract DFT methods have been used to study the reaction mechanism of 1-phenylethanol with benzyl alcohol catalyzed by ferrocenecarboxaldehyde/NaOH. The structures of intermediates and transition states, and the exchange of electronic density are computed in detail. In general, the catalyzed reaction is consists of three steps: hydride transfer step with the electron transfer, crossing-aldol condensation step, and the reduction step. Hydride transfer is the speed control step with the highest energy barrier (about 32 kcal/mol). Our calculation results are fundamentally coincident with the experimental detections, and manifest the crossing-coupling reaction occurs through a reliable mechanism.