The stereodynamics of 5,5’-disubstituted BIPHEPs
We investigated the stereodynamics of 5,5’-substituted tropos BIPHEP ligands (2,2’-bis(diphenylphosphino)-biphenyls) by enantioselective dynamic high-performance liquid chromatography (DHPLC) to elucidate the influence of the substitution pattern and electronics of the substituents (methyl, methoxy,...
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| Main Authors: | , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2013
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| In: |
Chirality
Year: 2012, Volume: 25, Issue: 2, Pages: 126-132 |
| ISSN: | 1520-636X |
| DOI: | 10.1002/chir.22125 |
| Online Access: | Verlag, Volltext: http://dx.doi.org/10.1002/chir.22125 Verlag, Volltext: https://onlinelibrary.wiley.com/doi/abs/10.1002/chir.22125 
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| Author Notes: | Frank Maier and Oliver Trapp |
| Summary: | We investigated the stereodynamics of 5,5’-substituted tropos BIPHEP ligands (2,2’-bis(diphenylphosphino)-biphenyls) by enantioselective dynamic high-performance liquid chromatography (DHPLC) to elucidate the influence of the substitution pattern and electronics of the substituents (methyl, methoxy, and hydroxyl groups). By temperature-dependent dynamic HPLC measurements the activation parameters ΔG╪, ΔH╪, and ΔS╪ could be determined with high precision, revealing that the activation barrier of these 5,5’-substituted BIPHEP ligands ranges in a narrow band between 87.8 and 93.0 kJ mol-1, making them highly attractive as deracemizable dynamic chiral ligands in asymmetric catalysis. Interestingly, the activation parameters are highly influenced by a hydroxyl or methoxy group in the 5,5’-position of the BIPHEP ligands. Chirality 25:126-132, 2013. © 2012 Wiley Periodicals, Inc. |
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| Item Description: | First published 22 December 2012 Gesehen am 10.08.2018 |
| Physical Description: | Online Resource |
| ISSN: | 1520-636X |
| DOI: | 10.1002/chir.22125 |