Functionalization of multi‐walled carbon nanotubes by the baclofen drug to immobilize palladium nanoparticles and catalyze Sonogashira coupling reactions

Abstract

The baclofen‐MWCNTs‐Pd nanocatalyst was synthesized through covalent grafting of baclofen molecules onto surface‐modified carbon nanotubes and immobilizing Pd nanoparticles by the baclofen ligands. The chemical structure of the produced nanocatalyst was studied by Raman spectroscopy, Fourier transform‐infrared spectroscopy, energy‐dispersive spectroscopy (EDS), elemental mapping and inductively coupled plasma analysis. Also, its surface morphology was determined using the scanning and transmission electron microscopy techniques. Furthermore, the obtained baclofen‐MWCNTs‐Pd nanocatalyst is demonstrated to exhibit very high activity as a heterogeneous phosphine‐free catalyst in Sonogashira cross‐coupling of aryl halides by giving good to excellent yields of different products. In addition, the nanocatalyst can be reused four times without any significant leaching or loss of activity.

Efficient removal of Pb(II) ions from aqueous solution by using a novel functionalized bio‐material with two tridentate coordinated units

“…These results indicated the successful bonding of 5‐aminomphthalic acid methyl ester to the surface of DAS through esterification. In the spectra of DAS2‐AT, the CO (amide I) and N − H (amide II) bending bonds were observed at 1656 and 1522 cm −1 , 36 respectively. This implied that –NH 2 group was grafted onto the surface of the functionalized DAS‐NH 2 .…”

Recent Expedition inPd‐CatalyzedSonogashira Coupling and Related Processes†

“…Later, a baclofen‐MWCNTs‐Pd nano‐ catalyst was introduced by Hekmati for the Sonogashira coupling. [ 100 ] The catalyst was prepared through covalent grafting of baclofen molecules onto surface‐modified multi‐walled carbon nanotubes and immobilizing PdNPs by the baclofen ligands. Aryl iodides and bromides were coupled with phenylacetylene with 0.2 mol% of the catalyst loading to give excellent yields.…”

Carbon‐Based Material‐Supported Palladium Nanocatalysts in Coupling Reactions: Discussion on their Stability and Heterogeneity

“…In addition, the supported catalyst prepared by pramipexole had no potential for large‐scale industrial application. Similarly, the same research group also recently reported the functionalization of MWCNTs by the drug baclofen to support Pd NPs and catalyze Sonogashira reactions …”