TY - JOUR
T1 - Preparation and characterization of a new bis-layered supported ionic liquid catalyst (SILCA) with an unprecedented activity in the Heck reaction
AU - Vucetic, Nemanja
AU - Virtanen, Pasi
AU - Nuri, Ayat
AU - Mattsson, Ida
AU - Aho, Atte
AU - Mikkola, Jyri-Pekka
AU - Salmi, Tapio
N1 - tk.
iok
2 February 2019
March 2019
post-print, 24 months, CC BY-NC-ND
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Har kontaktat [email protected] den 18.2.2020/LN
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PY - 2019
Y1 - 2019
N2 - A new bis-layered supported ionic liquid catalyst (SILCA) loaded with palladium was designed and successfully applied for the Heck reaction of iodobenzene and methyl acrylate. The silica modified catalyst consisting of the first ionic liquid layer – covalently anchored imidazolium bromide – on which the second layer, made of pyridine-carboxylic acid balanced with tetramethylguanidinium cation was attached, resulted in a catalyst with high activity. High turnover frequencies of 22,000 h−1 were achieved in reactions with a low palladium loading as 0.009 mol %. Lower TOFs, indicating on palladium dimerization was detected when higher amounts were used. The TMG cation had a purpose to recapture and stabilize the Pd nanoparticles thus followed a release and catch mechanism. In order to get a full understanding of the catalyst structure and behaviour, the catalyst was characterized by means of nitrogen physisorption, thermal gravimetric analysis, infrared spectroscopy, scanning electron and transmission electron microscopes, solid-state NMR, X-ray photoelectron spectroscopy and inductively coupled plasma spectroscopy. The catalyst preserved good activity in five cycles.
AB - A new bis-layered supported ionic liquid catalyst (SILCA) loaded with palladium was designed and successfully applied for the Heck reaction of iodobenzene and methyl acrylate. The silica modified catalyst consisting of the first ionic liquid layer – covalently anchored imidazolium bromide – on which the second layer, made of pyridine-carboxylic acid balanced with tetramethylguanidinium cation was attached, resulted in a catalyst with high activity. High turnover frequencies of 22,000 h−1 were achieved in reactions with a low palladium loading as 0.009 mol %. Lower TOFs, indicating on palladium dimerization was detected when higher amounts were used. The TMG cation had a purpose to recapture and stabilize the Pd nanoparticles thus followed a release and catch mechanism. In order to get a full understanding of the catalyst structure and behaviour, the catalyst was characterized by means of nitrogen physisorption, thermal gravimetric analysis, infrared spectroscopy, scanning electron and transmission electron microscopes, solid-state NMR, X-ray photoelectron spectroscopy and inductively coupled plasma spectroscopy. The catalyst preserved good activity in five cycles.
KW - Chemical Engineering
KW - Chemical Engineering
KW - Chemical Engineering
U2 - 10.1016/j.jcat.2019.01.029
DO - 10.1016/j.jcat.2019.01.029
M3 - Artikel
SN - 0021-9517
VL - 371
SP - 35
EP - 46
JO - Journal of Catalysis
JF - Journal of Catalysis
ER -