Design and preparation of a new Ni/Arg@zeolite-Y nano-composite: investigation of its performance as a multi-functional and bio-organic catalyst for the one-pot synthesis of thieno[2,3-<i>d</i>]pyrimidinones

This paper describes the design and fabrication of a Ni/Arg@zeolite-Y nanocomposite, and investigates its application as a multifunctional nanocatalyst in the one-pot synthesis of thieno[2,3-<i>d</i>]pyrimidinone derivatives. Herein, nickel metal ions were stabilized on NaY zeolite through a sodium exchange process (Ni@zeolite-Y). Then, this catalyst was functionalized <i>via</i> the linker 3-chloropropyltriethoxysilane with the basic l-arginine amino acid (Arg@zeolite-NiY). The structure of the nano-catalyst was confirmed using techniques such as FT-IR, XRD, BET, FE-SEM, TGA-DTA, and EDX-MAP. The catalytic activity of this nanocomposite in the green synthesis of thieno-pyrimidines was evaluated. Initially, the feasibility of conducting the reaction with this nano-catalyst was assessed through a one-pot reaction involving the cyclization of 2-amino-4,5,6,7-tetrahydrobenzo[<i>b</i>]thiophene-3-carboxamide with various aromatic aldehydes under different conditions. Subsequently, the reaction's generality for synthesizing thienopyrimidines under optimized conditions was successfully demonstrated. Key advantages of this project include the elimination of the toxic homogeneous catalyst hydrochloric acid and the use of green solvent ethanol. Additional benefits are the non-toxic nature, cost-effectiveness, recyclability of the nano-catalyst, ease of product isolation, high yield, and reduced reaction time.