Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study
Abstract
:1. Introduction
2. Results and Discussion
2.1. Synthesis of the Novel Ligands
2.2. Asymmetric Hydrogenation
3. Materials and Methods
3.1. Synthesis and Characterization of the New Compounds
3.1.1. Synthesis of 3-(((2S,4S)-4-(diphenylphosphino)pentan-2-yl)amino)propan-1-ol (L4)
3.1.2. Synthesis of 2-(((2S,4S)-4-(diphenylphosphino)pentan-2-yl)amino)propane-1,3-diol (L5)
3.1.3. Synthesis of 2-(((2S,3S)-3-(diphenylphosphino)butan-2-yl)amino)ethanol (L7)
3.1.4. Synthesis of (S)-2-((3-(diphenylphosphino)propyl)amino)propan-1-ol (L8)
3.1.5. Synthesis of 2-(((2S,4S)-4-(diphenylphosphino)pentan-2-yl)(methyl)amino)ethanol (L9)
3.1.6. Synthesis of (2R,4R)-4-(diphenylphosphino)-N-(2-methoxyethyl)-N-methylpentan-2-amine (L10)
3.1.7. Synthesis of (2S,4S)-4-(diphenylphosphino)pentan-2-amine (5)
3.1.8. Synthesis of 2-((((2S,4S)-4-(diphenylphosphino)pentan-2-yl)amino)methyl)phenol (L12)
3.2. Asymmetric Hydrogenation
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Entry | Base | B/C Molar Ratio | Solvent | Conversion (%) | ee (%) a |
---|---|---|---|---|---|
1 | tBuOLi | 5 | iPrOH | 76 | 88 |
2 | tBuOK | 5 | iPrOH | >99 | 82 |
3 | tBuOLi | 10 | iPrOH | >99 | 92 |
4 | tBuOLi | 20 | iPrOH | >99 | 92 |
5 | KOH | 10 | iPrOH | >99 | 80 |
6 | tBuOLi | 10 | MeOH | 98 | 72 |
7 | tBuOLi | 10 | EtOH | >99 | 94 |
8 | tBuOLi | 10 | nBuOH | >99 | 95 |
9 | tBuOLi | 10 | γ-valerolactone | 3 | 60 |
10 | tBuOLi | 10 | 2-Me-THF | 9 | 39 |
11 | tBuOLi | 10 | 96% EtOH | >99 | 93 |
12 b | tBuOLi | 10 | EtOH | >99 | 95 |
Substrate Concentration (mmol Acetophenone/mL Ethanol) | Conversion (%) | ee (%) |
---|---|---|
5 | >99 | 94 |
10 | >99 | 94 |
20 | >99 | 93 |
50 | >99 | 92 |
100 | >99 | 90 |
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Császár, Z.; Guóth, M.; Kovács, M.; Bényei, A.C.; Bakos, J.; Farkas, G. Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study. Molecules 2024, 29, 3743. https://doi.org/10.3390/molecules29163743
Császár Z, Guóth M, Kovács M, Bényei AC, Bakos J, Farkas G. Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study. Molecules. 2024; 29(16):3743. https://doi.org/10.3390/molecules29163743
Chicago/Turabian StyleCsászár, Zsófia, Mária Guóth, Margit Kovács, Attila C. Bényei, József Bakos, and Gergely Farkas. 2024. "Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study" Molecules 29, no. 16: 3743. https://doi.org/10.3390/molecules29163743
APA StyleCsászár, Z., Guóth, M., Kovács, M., Bényei, A. C., Bakos, J., & Farkas, G. (2024). Asymmetric Hydrogenation of Ketones by Simple Alkane-Diyl-Based Ir(P,N,O) Catalysts: A Comparative Study. Molecules, 29(16), 3743. https://doi.org/10.3390/molecules29163743