TY - JOUR
T1 - Multi-layered, covalently supported ionic liquid phase (mlc-SILP) as highly cross-linked support for recyclable palladium catalysts for the suzuki reaction in aqueous medium
AU - Gruttadauria, M.
AU - Salvo, A.M.P.
AU - Giacalone, F.
AU - Noto, R.
AU - Liotta, L.F.
AU - La Parola, V.
AU - Aprile, C.
N1 - Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2011/8/1
Y1 - 2011/8/1
N2 - The reaction between an excess of 1,4-bis(3-vinylimidazolium-1-yl) bromide and a mercaptopropyl-modified amorphous silica gel or ordered mesoporous silica SBA-15 in the presence of azobisisobutyronitrile (AIBN) afforded new materials, which have a high loading of imidazolium moieties. These materials, which contain a highly cross-linked polymeric network, have been denoted as multi-layered, covalently supported ionic liquid phase (mlc-SILP) and have been used as support for palladium catalysts containing a high loading of the metal (10 wt%). Such materials were characterized by several techniques ( C magic angle spinning nuclear magnetic resonance, the Brunauer-Emmett-Teller technique, small-angle X-ray scattering, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy). The presence of a homogeneous distribution of palladium nanoparticles was established. The palladium catalysts displayed good activity allowing the synthesis of several biphenyl compounds in high yields working with only 0.1 mol% of palladium loading at mild temperatures (room temperature or 50 °C) in ethanol/water. Reactions carried out on a 10-mmol scale required only 10 mg of catalysts. Good recyclability was observed.
AB - The reaction between an excess of 1,4-bis(3-vinylimidazolium-1-yl) bromide and a mercaptopropyl-modified amorphous silica gel or ordered mesoporous silica SBA-15 in the presence of azobisisobutyronitrile (AIBN) afforded new materials, which have a high loading of imidazolium moieties. These materials, which contain a highly cross-linked polymeric network, have been denoted as multi-layered, covalently supported ionic liquid phase (mlc-SILP) and have been used as support for palladium catalysts containing a high loading of the metal (10 wt%). Such materials were characterized by several techniques ( C magic angle spinning nuclear magnetic resonance, the Brunauer-Emmett-Teller technique, small-angle X-ray scattering, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy). The presence of a homogeneous distribution of palladium nanoparticles was established. The palladium catalysts displayed good activity allowing the synthesis of several biphenyl compounds in high yields working with only 0.1 mol% of palladium loading at mild temperatures (room temperature or 50 °C) in ethanol/water. Reactions carried out on a 10-mmol scale required only 10 mg of catalysts. Good recyclability was observed.
UR - http://www.scopus.com/inward/record.url?scp=80052002949&partnerID=8YFLogxK
U2 - 10.1002/adsc.201100186
DO - 10.1002/adsc.201100186
M3 - Article
AN - SCOPUS:80052002949
SN - 1615-4150
VL - 353
SP - 2119
EP - 2130
JO - Advanced Synthesis and Catalysis
JF - Advanced Synthesis and Catalysis
IS - 11-12
ER -