A Pd–Cu bimetallic catalyst supported on activated carbon for the efficient and selective reductive synthesis of procaine

Abstract

Green catalytic hydrogenation has been widely adopted in pharmaceutical synthesis due to its efficiency and environmental compatibility. However, industrial synthesis of procaine hydrochloride still predominantly relies on chemical reduction methods, which means green catalytic hydrogenation remains underutilized. This study presents a novel Pd–Cu bimetallic catalyst for the green hydrogenation synthesis of procaine hydrochloride. Compared with chemical reduction methods, this catalyst demonstrates a significantly enhanced reaction yield while addressing persistent challenges in traditional Pd/C catalytic hydrogenation systems, including agglomeration, instability, low selectivity, and poor activity. Comprehensive characterization, including field emission scanning electron microscope (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), was employed to analyze the structural and morphological properties of the synthesized catalysts. We reveal that the incorporation of an optimal copper content reduces the size of catalyst particles and increases the number of active sites. These structural advantages, combined with the introduction of copper, facilitate the adsorption of nitrogen-containing compounds, achieving a conversion rate of 99.7% and a selectivity of 99.1%, thereby effectively addressing the low-yield limitations of conventional catalytic hydrogenation. Furthermore, the catalyst exhibits excellent recyclability, maintaining its activity without significant loss of performance over multiple reaction cycles. These attributes position the Pd–Cu bimetallic system as a scalable and environmentally sustainable catalyst for industrial applications.

Graphical Abstract