Functionalization of mesoporous silicas as powders for support and immobilization of Pd catalysts and as monolithic framework for building strong lightweight materials

Author

Xiaojiang Wang

Keywords and Phrases

Sonogashira coupling

Abstract

"Immobilization of catalysts is a promising approach to combine the advantages of heterogeneous and homogeneous catalysts. Pd(PPh₃)₂Cl₂ known as an extremely active homogeneous catalyst for the Sonogashira coupling reaction has been immobilized on high surface area MCF (mesocellular foams)-type mesoporous silica powder modified with 3-aminopropyltriethoxysilane (APTES). The functionalized MCF-type silica and supported catalysts have been characterized by FTIR, BET, and Elemental Analysis. Such supported Pd catalysts have proven to be useful reagents for copper-, and amine-free Sonogashira reactions for the coupling of haloaromatic compounds and alkynes.

Monolithic pure silica gels with macro-mesoporous structure have been synthesized via a sol-gel process from tetramethoxysilane (TMOS) using Pluronic P123 as a structure-directing agent and 1,3,5-trimethylbenzene (TMB) as a micelle-swelling reagent. The template P123 can be removed completely by Soxhlet extraction using CH₃CN as a solvent and the samples were dried with CO₂ taken out super critically, resulting in materials with minimal shrinkage. The mechanical properties of such monolithic pure silica gels can be improved by introducing and letting a di-isocyanate (N3200) react with silanol groups on the surface of the silica"--Abstract, page iv.

Advisor(s)

Leventis, Nicholas
Sotiriou-Leventis, Lia

Committee Member(s)

Isaac, Kakkattukuzhy M.

Department(s)

Chemistry

Degree Name

M.S. in Chemistry

Publisher

University of Missouri--Rolla

Publication Date

Fall 2006

Journal article titles appearing in thesis/dissertation

• Immobilization of Pd catalysts on mesoporous silicas for amine-, and copper-free Sonogashira coupling reactions
• Conformal polymer nano-encapsulation of ordered mesoporous silica monoliths for improved mechanical properties

Pagination

x, 55 pages

Note about bibliography

Includes bibliographical references (pages 53-54)

Rights

© 2006 Xiaojiang Wang, All rights reserved.

Document Type

Thesis - Restricted Access

File Type

text

Language

English

Subject Headings

Catalysts -- TestingPorous materialsSilica

Thesis Number

T 9115

Print OCLC #

156787026

Recommended Citation

Wang, Xiaojiang, "Functionalization of mesoporous silicas as powders for support and immobilization of Pd catalysts and as monolithic framework for building strong lightweight materials" (2006). Masters Theses. 5905.
https://scholarsmine.mst.edu/masters_theses/5905