| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 3.86 MB | Adobe PDF |
Advisor(s)
Abstract(s)
A series of derivative C-scorpionate rhenium complexes, i.e., [ReCl2{NNC(O)C6H5} (Hpz)(PPh3)2] (A) (where Hpz is pyrazole), [ReCl2{NNC(O)C6H5}(Hpz)2(PPh3)] (B), [ReClF {NNC(O)C6H5}(Hpz)2(PPh3)] (C), and their precursor [ReOCl3(PPh3)2] (D), immobilized on 3-aminopropyl-functionalized silica have been prepared and used for neat O2 oxidation of n-hexane and n-heptane mainly to the corresponding alcohols and, in lower amounts, ketones. The supported catalyst C, with fluoro- and diazenido-ligands, exhibits the highest activity for both alkanes (overall turnover numbers (TONs) up to 3.8 _ 103 and 2.5 _ 103, for n-hexane and n-heptane, respectively) and can be reused in consecutive catalytic cycles. Improved conversion was observed after addition of hetero-carboxylate co-catalysts. A free-radical-based mechanism is proposed to explain the product formation.
Description
Keywords
Rhenium Scorpionate derivative Immobilization Supported catalysis N-alkane Oxidation Molecular oxygen Product selectivity Radical mechanism
Citation
MISHRA, Gopal S.; ALEGRIA, Elisabete C. B. A.; POMBEIRO, Armando J. L.; MARTINS, Luísa M. D. R. S. – Highly active and selective supported rhenium catalysts for aerobic oxidation of n-Hexane and n-Heptane. ISSN 2073-4344. Vol. 8, N.º 3 (2018), pp. 1-16
Publisher
MDPI