Lewis Acid–Base Pairs Constructed via Lattice Regulation for Ultrafast Catalytic Transfer Hydrogenation

Abstract

Catalytic transfer hydrogenation (CTH) strongly relies on the synergistic interaction between Lewis acid and Lewis base. Highly active, high-density, and well-dispersed Lewis acid–base pairs (LP) are crucial to achieving efficient CTH catalysis, yet forming such an ideal interface remains challenging. To address this, a novel construction strategy is presented, which leverages the regulation of the layered double hydroxide (LDH) lattice structure to establish an ideal LP interface. Supercritical isopropyl alcohol (SCIP) was employed to selectively remove hydroxyl groups and hydrogen bonds from the NiAl-LDH surface, constructing rich M_CUS and Ni-OOH at the LDH interface in a simple, controllable, and environmentally friendly way. The formation process of M_CUS and Ni-OOH in SCIP was analyzed using a series of dynamic characterization. Key factors restricting the formation of M_CUS and Ni-OOH were identified by comparing results across different precursor preparation methods and temperatures of SCIP treatment. On this basis, the one-pot reaction system was established. Within this system, catalyst preparation and the CTH of ethyl levulinate (EL) to γ-valerolactone (GVL) co-occur. The system simplifies the CTH reaction process and exhibits ultrahigh catalytic efficiency, with a GVL formation rate of 0.780 mol_GVL·g^–1·h^–1. Compared to traditional reaction systems and catalysts, the developed one-pot reaction system and catalyst demonstrates significant advantages and exhibit excellent cyclic stability after catalyst stabilization. The combination of the LP interface and the one-pot reaction system enabled environmentally friendly, economical, and efficient biomass-based GVL synthesis.