The Immobilization of a Transfer Hydrogenation Catalyst on Colloidal Particles

Abstract

In this paper, we report a new synthetic procedure to immobilize a transfer hydrogenation catalyst on the surface of colloidal polystyrene particles. Using supports of colloidal dimensions allows for combining a relatively high surface area for catalyst binding, mobility of the catalyst, and facile recovery by centrifugation or sedimentation. The immobilization procedure relies on the covalent attachment of terpyridine moieties on the particle surface. These immobilized terpyridines are subsequently employed as colloidal ligands, which participate in the formation of an active ruthenium‐based transfer hydrogenation catalyst. The resulting functional colloidal particles successfully catalyze the transfer hydrogenation of acetophenone with 2‐propanol as the hydrogen donor. Thorough analysis of the chemical composition of the colloidal surface led to the determination of the catalyst loading per particle. This enabled us to conduct reference hydrogenations with equal concentrations of the homogeneous transfer hydrogenation catalyst to probe the effect of the immobilization procedure on the catalytic activity. Despite a decrease in transfer hydrogenation activity, full acetophenone conversion is still achievable within 24 h. Preliminary experiments show that the catalytic colloids are recyclable without significant loss of transfer hydrogenation activity.

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Screening of peptide probe binding to particulate matter with a high metal content

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Electrooxidation of organic compounds using some principles of green chemistry

“…In particular, ruthenium complexes have been used in several processes as, for example, catalytic hydrogenation ( VAN RAVENSTEIJN et al, 2017), transformation of amines in nitriles (CRISTIAN et al, 2013). It is worthy to note that some ruthenium complexes have been successfully used in solar cells (AMETA; AMETA, 2016; AGHAZADA; NAZEERUDDIN, 2018); In medical research, some studies have shown that ruthenium (II) complexes are useful as a new generation of antitumor drugs (LIN et al, 2018), since they exhibit higher efficiency and lower toxicity when compared to the platinum complexes that are commonly used (ABID; SHAMSI; AZAM, 2016;THOTA et al, 2018).…”