Cart
Article
Grafted Metallocalixarenes as Single-Site Surface Organometallic Catalysts
Full Text HTML
Hi-Res PDFPurchase the full-text
- PDF/HTML,
figures/images,
references and tables,
(where available)
Section:Abstract
Metallocalixarenes were grafted onto silica using a surface organometallic approach and shown to be active and selective catalysts for epoxidation of alkenes using organic hydroperoxides. Calixarene−TiIV precursors were anchored at surface densities from 0.1 to near-monolayer coverages (0.025−0.25 calixarene nm-2). Several spectroscopic methods independently detected calixarene−TiIV connectivity before and after epoxidation catalysis. Kinetic analyses of cyclohexene epoxidation confirmed that the active sites were anchored on the silica surface and were significantly more active than their homogeneous analogues. The steric bulk and multidentate binding of the calixarenes led to structural stability and to single-site behavior during epoxidation catalysis. Rate constants were independent of surface density for cyclohexene epoxidation with tert-butyl hydroperoxide (11.1 ± 0.3 M-2 s-1) or cumene hydroperoxide (25 ± 2 M-2 s-1). The materials and methods reported here allow the assembly of robust surface organometallic structures in which the active sites behave as isolated species, even near saturation monolayer coverages. In turn, this makes possible the rational design and synthesis of a class of heterogeneous oxide catalysts with atomic-scale precision at the active site.
Citing Articles
Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.
This article has been cited by 16 ACS Journal articles (5 most recent appear below).
Enhanced and Selective Degradation of Pollutants over Cyclodextrin/TiO2 under Visible Light Irradiation
Xu Zhang, Xuankun Li, and Nansheng DengIndustrial & Engineering Chemistry Research2012 51 (2), 704-709Enhanced and Selective Degradation of Pollutants over Cyclodextrin/TiO2 under Visible Light Irradiation
Xu Zhang, Xuankun Li, and Nansheng DengIndustrial & Engineering Chemistry Research2012 51 (2), 704-709The photocatalytic performance of cyclodextrin modified TiO2 (TiO2/β-CD) on the degradation of rhodamine B and bisphenol A (BPA) was studied in this work. The interactions between β-CD and TiO2 varied as the synthesis method changes. When applying TiO2/β-...
Facile Synthesis of Bismuth(III) and Antimony(III) Complexes Supported by Silylated Calix[5]arenes.
Daniel Mendoza-Espinosa and Tracy A. HannaInorganic Chemistry2009 48 (21), 10312-10325Facile Synthesis of Bismuth(III) and Antimony(III) Complexes Supported by Silylated Calix[5]arenes.
Daniel Mendoza-Espinosa and Tracy A. HannaInorganic Chemistry2009 48 (21), 10312-10325A series of bismuth(III) and antimony(III) complexes supported by silicon-containing calix[5]arene ligands were synthesized and fully characterized by NMR, X-ray, IR, mp, UV/vis, and elemental analysis. Reaction of the para-tert-butylcalix[5]arene [tBuC5(...
Vanadocalixarenes on Silica: Requirements for Permanent Anchoring and Electronic Communication
Namal de Silva, Son-Jong Hwang, Kathleen A. Durkin and Alexander KatzChemistry of Materials2009 21 (9), 1852-1860Vanadocalixarenes on Silica: Requirements for Permanent Anchoring and Electronic Communication
Namal de Silva, Son-Jong Hwang, Kathleen A. Durkin and Alexander KatzChemistry of Materials2009 21 (9), 1852-1860Grafted metallocalixarene complexes that are 1,3-disubstituted at the lower rim have been synthesized. Spectroscopic characterization of these materials indicates enhanced electronic communication between metal center and methoxy substituents and suggests ...
Optimizing Acid−Base Bifunctional Mesoporous Catalysts for the Henry Reaction: Effects of the Surface Density and Site Isolation of Functional Groups
Krishna K. Sharma, Robert P. Buckley and Tewodros AsefaLangmuir2008 24 (24), 14306-14320Optimizing Acid−Base Bifunctional Mesoporous Catalysts for the Henry Reaction: Effects of the Surface Density and Site Isolation of Functional Groups
Krishna K. Sharma, Robert P. Buckley and Tewodros AsefaLangmuir2008 24 (24), 14306-14320We report on the effects of the surface density and the spacing between grafted organoamines (and residual ungrafted silanols) of amine-functionalized mesoporous materials on their (cooperative) catalytic activity in the Henry reaction. The spacing ...
A Noncentrosymmetric 3D Coordination Polymer of Metallocalix[4]arene
Yu-Juan Liu, Jie-Sheng Huang, Stephen Sin-Yin Chui, Cheng-Hui Li, Jing-Lin Zuo, Nianyong Zhu and Chi-Ming CheInorganic Chemistry2008 47 (24), 11514-11518A Noncentrosymmetric 3D Coordination Polymer of Metallocalix[4]arene
Yu-Juan Liu, Jie-Sheng Huang, Stephen Sin-Yin Chui, Cheng-Hui Li, Jing-Lin Zuo, Nianyong Zhu and Chi-Ming CheInorganic Chemistry2008 47 (24), 11514-11518Sequential reaction of a lower-rim functionalized calix[4]arene (H2LC4) with K2CO3 and CoCl2·6H2O in ethanol afforded a noncentrosymmetric 3D coordination polymer [K3Co2(LC4)3(EtOH)6]Cl (1). The crystal structure of 1 features a noninterpenetrated (10,3)-...
Tools
-
Add to Favorites
-
Download Citation
-
Email a Colleague -
Permalink
Order Reprints
Rights & Permissions
Citation Alerts
History
- Published In Issue December 22, 2004
- Received May 20, 2004
ACS
Network
Facebook
Tweet This
CiteULike
Newsvine
Digg This
Delicious
