| dc.creator |
Hamad, Fatma B. |
|
| dc.date |
2016-06-18T18:12:34Z |
|
| dc.date |
2016-06-18T18:12:34Z |
|
| dc.date |
2013 |
|
| dc.date.accessioned |
2018-03-27T08:54:36Z |
|
| dc.date.available |
2018-03-27T08:54:36Z |
|
| dc.identifier |
Hamad, F., 2013. Novel ruthenium indenylidene catalysts: from homogeneous to heterogeneous (Doctoral dissertation, Ghent University). |
|
| dc.identifier |
http://hdl.handle.net/20.500.11810/2573 |
|
| dc.identifier.uri |
http://hdl.handle.net/20.500.11810/2573 |
|
| dc.description |
Nowadays a number of ruthenium metathesis catalysts have been developed owing to their accessibility, remarkable activity and selectivity, connected with good tolerance towards functional groups, air and moisture. Innovative development in the class of ruthenium metathesis catalysts coordinated with NHC has been experienced which mainly directed toward tuning their catalytic activity and selectivity through altering both steric and electronic properties. The unsymmetrical NHC ligands in particular, have been introduced to induce dissymmetry, a key for achieving higher level of selectivity in different reactions. A great number of the ruthenium complexes bearing unsymmetrical NHC ligands have been developed up to this moment. The bis-coordinated ruthenium indenylidene developed in this work showed moderate activity at higher temperature in RCM, ROMP and other kind of reactions such as isomerization of allylic alcohols and isomerization of alkenes. Failure of these catalysts to work at room temperature has been attributed to the lack of labile ligand.This call for further research which will focus on tuning of unsymmetrical NHC ligands to achieve more active and selective ruthenium complexes coordinated with non-labile NHC ligand with the labile one. The research should go in hand with design and synthesis of heterogeneous catalysts that can be recovered from the reaction mixture and be recycled. Although the support materials used in this study proved to be not suitable for metathesis, the obtained results can be considered as a challenge in the journey toward designing stable and active heterogeneous ruthenium indenylidene catalysts. Up to now a number of solid materials have been developed and successfully utilized in the immobilization of ruthenium benzylidene complexes. It is expected that the same materials can act as the suitable supports for ruthenium indenylidene and therefore, a study about development heterogeneous ruthenium indenylidene analogs would be of great interest. |
|
| dc.language |
en |
|
| dc.title |
Novel Ruthenium Indenylidene Catalysts: From Homogeneous to Heterogeneous |
|
| dc.type |
Doctorate Thesis |
|