Bifunctional mesoporous silica nanoparticles as cooperative catalysts for the Tsuji–Trost reaction – tuning the reactivity of silica nanoparticles
作者:Arne T. Dickschat、Frederik Behrends、Sabrina Surmiak、Mark Weiß、Hellmut Eckert、Armido Studer
DOI:10.1039/c3cc00235g
日期:——
Bifunctional mesoporous silica nanoparticles (MSNs) bearing Pd-complexes and additional basic sites were prepared and tested as cooperative active catalysts in the TsujiâTrost allylation of ethyl acetoacetate. Functionalization of the MSNs was realized by postmodification using click-chemistry. The selectivity of mono versus double allylation was achieved by control of reaction temperature and the nature of the catalyst.
Preparation of Bifunctional Mesoporous Silica Nanoparticles by Orthogonal Click Reactions and Their Application in Cooperative Catalysis
作者:Arne T. Dickschat、Frederik Behrends、Martin Bühner、Jinjun Ren、Mark Weiß、Hellmut Eckert、Armido Studer
DOI:10.1002/chem.201200499
日期:2012.12.21
The synthesis of bifunctionalmesoporoussilicananoparticles is described. Two chemically orthogonal functionalities are incorporated into mesoporoussilica by co‐condensation of tetraethoxysilane with two orthogonally functionalized triethoxyalkylsilanes. Post‐functionalization is achieved by orthogonal surface chemistry. A thiol–ene reaction, Cu‐catalyzed 1,3‐dipolar alkyne/azide cycloaddition,
Pd Immobilized in Mesoporous Silica Particles as Recyclable Catalysts for Suzuki-Miyaura Coupling: Cooperative Effects Exerted by Co-Immobilized Amine Functionalities
作者:Armido Studer、Arne Dickschat、Sabrina Surmiak
DOI:10.1055/s-0033-1339183
日期:——
A bifunctional heterogeneous palladium catalyst bearing additional basic sites was successfully prepared by sequential Cu-catalyzed 1,3-dipolar alkyne-azide cycloaddition and thermal nitroxide-exchange reaction of surface-bound alkoxyamines. This catalyst shows high activity in the Suzuki-Miyaura cross-coupling. The additional basic functionality acts cooperatively since an analogous heterogeneous Pd catalyst lacking the amine functionality is less active. Such catalysts can be recycled up to ten times without loss of activity.
Site-Selective Surface-Initiated Polymerization by Langmuir–Blodgett Lithography
作者:Marion K. Brinks、Michael Hirtz、Lifeng Chi、Harald Fuchs、Armido Studer