A New ۱,۱۰-Phenenthroline-Pd(II) Complex Supported on SBA-۱۵ for the Carboxylation of Aryl Halides

Carbonylation refers to the metal-catalyzed incorporation of carbon monoxide into aryl/benzyl/vinyl halides or related compounds to give carboxylic acid derivatives. In recent decades, most studies have been directed at CO-free carbonylation reactions. Various carbon monoxide surrogates such as Mo(CO)۶, acetic formic anhydride, paraformaldehyde, HCOOH, and oxalic acid have been used as carbonyl sources. Among the mentioned CO sources, formic acid has found a special place due to easy decomposition to CO and water at elevated temperatures in acidic media. Furthermore, formic acid is a cost-effective, environmentally friendly, and available CO source. [۱]. The present study describes the synthesis, characterization, and use of a new supported catalyst, SBA-۱۵@PHEN-Pd(II) for the preparation of benzoic acids from haloarenes. ۵-nitro-۱,۱۰-phenanthroline was prepared from the nitration of the ۱,۱۰-phenanthroline with concentrated nitric acid and subsequent reduction with Pd/C and hydrazin to give ۵-amio-۱,۱۰-phenanthroline. The surface of SBA-۱۵ was successively treated with (۳-chloropropyl) triethoxysilane (CPTES), ۵-amino-۱,۱۰-phenanthroline, and PdCl۲ to afford SBA-۱۵@PHEN-Pd(II), Scheme ۱. The catalyst was characterized by FT-IR, XRD, TGA, EDX, and BET. The catalytic potential of the supported PHEN-Pd(II) complex was explored for the preparation of carboxylic acids from the corresponding aryl halieds. The catalyst could be easily removed from the reaction mixture by centrifuging, and reused in subsequent runs.

کلیدواژه ها:

Supported catalyst ، Nitration ، Carboxylation