Facile preparation of ultrafine Pd nanoparticles anchored on covalent triazine frameworks catalysts for efficient N-alkylation.

Abstract The fabrication of stable and efficient catalysts for green and economic catalytic transformation is significant. Here, highly stable covalent triazine frameworks (CTF-1) were used as the supporting material for anchoring ultrafine Pd nanoparticles (NPs) via a facile impregnation process and a one-pot calcination-reduction strategy. The widespread dispersion of ultrafine Pd NPs was a result of the abundant high nitrogen-content triazine groups of CTF-1 that endowed the catalyst Pd@CTF-1 with high catalytic activity. The catalytic performance of Pd@CTF-1 was demonstrated by the one-pot N-alkylation of benzaldehyde with aniline (or nitrobenzene) under mild reaction conditions, and Pd@CTF-1 exhibited a wide range of general applicability for N-alkylation reactions. The reaction mechanism for the N-alkylation reaction was also studied in detail. In addition, the Pd@CTF-1 catalyst exhibited high thermal and chemical stability, maintaining good catalytic efficiency after multiple reaction cycles. This study provides new insights for the fabrication of organic supporting materials with highly dispersed active catalytic sites that can lead to excellent catalytic performance for efficient, economical, and green reactions.