Templating effect of carbon nanoforms on highly cross‐linked imidazolium network: Catalytic activity of the resulting hybrids with Pd nanoparticles. (30th April 2019)

• Record Type: Journal Article
• Authors: Campisciano, Vincenzo; Calabrese, Carla; Liotta, Leonarda Francesca; La Parola, Valeria; Spinella, Alberto; Aprile, Carmela; Gruttadauria, Michelangelo; Giacalone, Francesco
• Is Part Of: Applied organometallic chemistry. Volume 33:Number 7(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-04-30
• Subjects: C‐C coupling -- Heck reaction -- heterogeneous catalysis -- nanotubes -- Suzuki–Miyaura reaction; Organometallic chemistry -- Periodicals; Organometallic compounds -- Periodicals; 547.05
• DOI: 10.1002/aoc.4848
• Languages: English
• ISSNs: 0268-2605

Abstract

Abstract : Two different carbon nanoforms (CNFs), namely multi‐walled carbon nanotubes (MWCNTs) and carbon nanohorns (CNHs), have been chosen as support for the direct polymerization of a bis‐vinylimidazolium salt. Transmission electron microscopy analyses revealed a templating effect of the CNFs on the growth of the polymeric network, which perfectly covers their whole surfaces creating a cylindrical or spherical coating for MWCNTs and CNHs, respectively. Subsequently, the CNFs‐polyimidazolium have been used as stabilizers for Pd nanoparticles (Pd NPs), and the obtained materials have been characterized by means of analytical and spectroscopic techniques and then employed as easily recoverable and recyclable catalysts for Suzuki and Heck reactions. Quantitative conversions have been obtained in almost all the explored reactions, even employing low loading of catalyst (down to 0.007 mol%). Suzuki reactions were carried out in pure water under aerobic conditions. Both materials showed excellent activity and recyclability for the investigated C‐C coupling reactions, with the CNHs‐based material resulting slightly more active than the MWCNTs‐based one due to a higher superficial exposure of Pd NPs. Abstract : Wrapping two carbon nanoforms, MWCNTs and CNHs, with a highly cross‐linked polyimidazolium salt gave suitable materials where palladium nanoparticles were well dispersed. The catalytic materials showed high activity and recyclability for Suzuki and Heck reactions.