Synfacts 2005(0): 0078-0078  
DOI: 10.1055/s-2005-869880
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

Cooperative Catalysis by General Acid and Base Bifunctionalized Mesoporous Silica Nanospheres

Contributor(s): Yasuhiro Uozumi, Masahiro Kimura
S. Hun, H.-T. Chen, J. W. Wiench, M. Pruski, V. S.-Y. Lin*
Iowa State University, USA
Cooperative Catalysis by General Acid and Base Bifunctionalized Mesoporous Silica Nanospheres
Angew. Chem. Int. Ed.  2005,  44:  1826-1830  
Further Information

Publication History

Publication Date:
20 July 2005 (online)


Significance

Bifunctinalized mesoporous silica nanospheres (MSNs) having a general acid, the ureidopropyl group (UDP), and a general base, 3-[2-(2-aminoethylamino)ethylamino]propyl group (AEP), were synthesized. The AEP/UDP-MSNs catalyzed the carbonyl activation reactions, aldol reaction, Henry reaction, and cyanosilylation with high TONs up to 22.6, 125.0, and 276.1, respectively.

Comment

Recently, a new synthetic method to functionalize mesoporous silica with multiple organic groups was reported from the author’s group, by which the loading of functional groups, particle size, and shape of the mesoporous silicas could be controlled (for example, see: S. Huh, J. W. Wiench, J.-C. Yoo, M. Pruski, V. S.-Y. Lin Chem. Mater. 2003, 15, 4247-4256). The authors discussed that the AEP and the UDP activate both the nucleophile and the electrophile at the same time, cooperatively.