Micellar templates and spectroscopic rulers for synthesis and characterization of site-isolated inorganic catalysts

ANYL 173

Brittni A Scruggs, brittni.scruggs@trinity.edu1, Suzanna L Kilgore, suzanna.kilgore@trinity.edu1, Brent H. Shanks, bshanks@iastate.edu2, and Bert D Chandler, bert.chandler@trinity.edu1. (1) Department of Chemistry, Trinity University, One Trinity Place, San Antonio, TX 78212, (2) Department of Chemical and Biological Engineering, Iowa State University, 2119 Sweeney Hall, Ames, IA 50011-2230
The controlled preparation of active sites on heterogeneous catalysts could improve several catalyst systems. CTAB micelles were used as surface templating agents for the encapsulation and deposition of aminopropyltriethoxysilane (APS) onto silica. The number of active sites on each material was determined using spectroscopic measurements of cobalt(II) titrations and ninhydrin tests. Further characterization of the active sites after micelle removal and surface alkylation with tetramethyldisilazane (TMDS) was performed using fluorescence resonance energy transfer (FRET). Indole-3-propionic acid, a fluorescence donor, and a variety of fluorescence acceptor molecules have been reacted with the surface amines on APS micelle-templated and APS grafted silica to provide a distribution of distances between the amines using the Förster radii of the specific donor and acceptor pairs. These FRET studies will determine the extent of isolation of the active sites on oxide supports using the proposed templating scheme. The extension of these techniques to the preparation of site-isolated catalysts for amide-bond formation will be discussed.
 

Directed Assemblies Using Surface Templates
8:25 AM-12:05 PM, Wednesday, April 9, 2008 Morial Convention Center -- Rm. 335, Oral

Division of Analytical Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008