Planar chiral Rh(I) dibenzo[a,e]cyclooctatetraene complexes: synthesis and application in asymmetric catalysis
(2022) KEMP30 20221Department of Chemistry
- Abstract
- is an important area of study with implications for pharmaceutical development. Asymmetric catalysis is one way to perform enantioenriched products.
To study this subject, enantiomerically pure Rh(I) complexes were synthesized to be applied as catalysts in these kinds of reactions.
A new C2 symmetric dibenzo[a,e]cyclooctatetraene-ligand, 5,11-bis(3,5-bis(trifluoromethyl)phenyl dibenzo[a,e]cyclooctatetraene, was synthesized in just two steps from commercially available materials. The racemic ligand was thereafter resolved using preparative HPLC. The enantiomerically pure ligand was then complexed with Rh(I) to give the catalyst.
This catalyst was then evaluated in 1,2 and 1,4-addition asymmetric reactions. The catalyst showed poor... (More) - is an important area of study with implications for pharmaceutical development. Asymmetric catalysis is one way to perform enantioenriched products.
To study this subject, enantiomerically pure Rh(I) complexes were synthesized to be applied as catalysts in these kinds of reactions.
A new C2 symmetric dibenzo[a,e]cyclooctatetraene-ligand, 5,11-bis(3,5-bis(trifluoromethyl)phenyl dibenzo[a,e]cyclooctatetraene, was synthesized in just two steps from commercially available materials. The racemic ligand was thereafter resolved using preparative HPLC. The enantiomerically pure ligand was then complexed with Rh(I) to give the catalyst.
This catalyst was then evaluated in 1,2 and 1,4-addition asymmetric reactions. The catalyst showed poor enantiomeric excess but high yields in a 1,2-addition reaction and a good enantiomeric excess but low yields in a 1,4-addition reaction.
The choice to study this ligand rather than other options, was due to the fact that previous unpublished studies in Strand group had shown good results with 5,11-bis(4-trifluoromethyl)phenyl) dibenzo[a,e]cyclooctatetraene. So, it was thought that adding two more trifluoromethyl groups might improve the results.
Moreover, as part of this study, [RhCl((p-MeOH)Ph)2dbCOT]2 and [RhCl(Ph2dbCOT)]2 were also synthesized. (Less) - Popular Abstract
- According to the Oxford Advanced Learner’s Dictionary, a catalyst is defined as “a substance that makes a chemical reaction happen faster without being changed itself”.
Nowadays, 90% of chemical industry processes rely on catalysts. Applications include the transformation of petroleum into plastic, the production of fertilizers, food, medicines and the purification of air from harmful pollutants.1
In this thesis, three catalysts have been synthesized in enantiomerically pure form. Two enantiomers are molecules with the same atoms but they are mirror images that cannot be superposed. This property is called . Enantiomers have the same physical properties but opposite specific rotation [α]. When used as catalysts in a chemical reaction,... (More) - According to the Oxford Advanced Learner’s Dictionary, a catalyst is defined as “a substance that makes a chemical reaction happen faster without being changed itself”.
Nowadays, 90% of chemical industry processes rely on catalysts. Applications include the transformation of petroleum into plastic, the production of fertilizers, food, medicines and the purification of air from harmful pollutants.1
In this thesis, three catalysts have been synthesized in enantiomerically pure form. Two enantiomers are molecules with the same atoms but they are mirror images that cannot be superposed. This property is called . Enantiomers have the same physical properties but opposite specific rotation [α]. When used as catalysts in a chemical reaction, they give products with different chirality.
The main objective of this project was to synthesize enantiomerically pure rhodium catalysts and apply them in reactions with the hope of obtaining enantiomerically pure reaction products. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9099527
- author
- Sanchez Dana, Gemma LU
- supervisor
- organization
- course
- KEMP30 20221
- year
- 2022
- type
- H1 - Master's Degree (One Year)
- subject
- keywords
- Enantioselective synthesis, chirality, analytical chemistry
- language
- English
- id
- 9099527
- date added to LUP
- 2022-11-23 09:07:57
- date last changed
- 2022-11-23 09:07:57
@misc{9099527,
abstract = {{is an important area of study with implications for pharmaceutical development. Asymmetric catalysis is one way to perform enantioenriched products.
To study this subject, enantiomerically pure Rh(I) complexes were synthesized to be applied as catalysts in these kinds of reactions.
A new C2 symmetric dibenzo[a,e]cyclooctatetraene-ligand, 5,11-bis(3,5-bis(trifluoromethyl)phenyl dibenzo[a,e]cyclooctatetraene, was synthesized in just two steps from commercially available materials. The racemic ligand was thereafter resolved using preparative HPLC. The enantiomerically pure ligand was then complexed with Rh(I) to give the catalyst.
This catalyst was then evaluated in 1,2 and 1,4-addition asymmetric reactions. The catalyst showed poor enantiomeric excess but high yields in a 1,2-addition reaction and a good enantiomeric excess but low yields in a 1,4-addition reaction.
The choice to study this ligand rather than other options, was due to the fact that previous unpublished studies in Strand group had shown good results with 5,11-bis(4-trifluoromethyl)phenyl) dibenzo[a,e]cyclooctatetraene. So, it was thought that adding two more trifluoromethyl groups might improve the results.
Moreover, as part of this study, [RhCl((p-MeOH)Ph)2dbCOT]2 and [RhCl(Ph2dbCOT)]2 were also synthesized.}},
author = {{Sanchez Dana, Gemma}},
language = {{eng}},
note = {{Student Paper}},
title = {{Planar chiral Rh(I) dibenzo[a,e]cyclooctatetraene complexes: synthesis and application in asymmetric catalysis}},
year = {{2022}},
}