CRC 858 B01 - Cooperative Catalysis at Surfaces - a Combinatorial Approach (SFB 858)

Basic data for this project

Description

The generation of inorganic-organic hybrid material is one of the major issues within the first project (B1) in project area B. We plan to utilize these hybrid materials as bi- and multifunctional catalysts systems acting in a cooperative manner. Porous SiO2 with defined pore diameter shall be applied as an inorganic support. Functionalization of this material can be achieved by treatment with trialkoxysilanes or trichloroalkylsilanes, respectively, with SiOH units at the surface, leading to particles bearing alkene-, alkyne- and azide-moieties. These three functionalities can be adressed chemoselectively in orthogonal processes by a) the Cu-free Huisgen-[3+2]-alkyne-azide-cycloaddition, b) its Cu-catalyzed pendant and c) radical carboaminoxylation. Such orthogonal processes allow the installation of different functional groups in a combinatorial approach ("one-bead/one-compound"-strategy). They might act as cooperative active units (mainly acid/base-pairs) being "frustrated" at the surface via local separation. As proof of principle, aldol-, Michael- and Baylis-Hillman reactions shall be performed. Finally this approach may lead to tri- and tetrafunctional, cooperative active catalyst systems. Catalyst separation and recycling should be accessible by centrifugation or simple filtration. Kinetic cooperative effects shall be determined experimentally by generation and analysis of the corresponding reference systems.