Efficient and selective N-benzylation of amines using Pd-doped La-BDC MOF

Abstract

Transition metal catalysis has become increasingly important in direct N-alkylation via the hydrogen borrowing mechanism, an environmentally friendly pathway that produces only water as a by-product. However, the application of inner-transition metal catalysts for the alkylation of amines has been explored on a limited scale. Herein, we investigate the potential of a Pd-doped La-BDC (benzene-1,4-dicarboxylate, terephthalic acid) MOF in the N-benzylation of amine substrates. The isolation of imine and benzaldehyde intermediates confirms that the reaction follows a hydrogen auto-transfer pathway. Reaction conditions, including temperature, reaction time, and catalyst loading, were optimized to achieve high conversion and selectivity. Extensive characterization using FTIR, FESEM, HRTEM, EDS, XPS, and nitrogen adsorption–desorption measurements assessed the structural and textural properties of the synthesized Pd@La-BDC MOF. Compared to previous literature, our findings provide valuable insights into the application of La-derived MOFs in sustainable catalysis and offer new possibilities for synthesizing N-benzylated products using benzyl alcohol as an alkylating agent.