Effect of a Substituent in Cyclopentadienyl Ligand on Iridium-Catalyzed Acceptorless Dehydrogenation of Alcohols and 2-Methyl-1,2,3,4-tetrahydroquinoline
Abstract
:1. Introduction
2. Results
3. Materials and Methods
3.1. General
3.2. Procedures for the Synthesis of (CpRIrCl2)2
3.2.1. (η5-C5Me4H)IrCl2)2 (CAS: 835614-43-2) (1a)
3.2.2. (Cp*EthylIrCl2)2 (CAS: 2050480-26-5) (1c)
3.2.3. (Cp*iPrIrCl2)2 (CAS: 1621315-48-7) (1d)
3.2.4. (Cp*tBuIrCl2)2 (1e)
3.3. Procedures for the Synthesis of (CpRIr(6,6′-dihydroxy-2,2′-bipyridine)Cl)Cl
3.3.1. ((η5-C5Me4H)Ir(6,6′-dihydroxy-2,2′-bipyridine)Cl)Cl (2a)
3.3.2. (Cp*EthylIr(6,6′-dihydroxy-2,2′-bipyridine)Cl)Cl (2c)
3.3.3. (Cp*iPrIr(6,6′-dihydroxy-2,2′-bipyridine)Cl)Cl (2d)
3.3.4. (Cp*tBuIr(6,6′-dihydroxy-2,2′-bipyridine)Cl)Cl (2e)
3.4. Procedures for the Synthesis of CpRIr(2.2′-bipyridine-6,6′-dionato)H2O
3.4.1. (η5-C5Me4H)Ir(2,2′-bipyridine-6,6′-dionato)H2O (3a)
3.4.2. Cp*EthylIr(2,2′-bipyridine-6,6′-dionato)H2O (3c)
3.4.3. Cp*iPrIr(2,2′-bipyridine-6,6′-dionato)H2O (3d)
3.4.4. Cp*tBuIr(2,2′-bipyridine-6,6′-dionato)H2O (3e)
3.5. Investigation of Catalytic Activity in Dehydrogenation of 1-Phenylethanol (4)
3.6. Investigation of Catalytic Activity in Dehydrogenation of Benzyl alcohol (6)
3.7. Investigation of Catalytic Activity in Dehydrogenation of 2-Octanol (8)
3.8. Investigation of Catalytic Activity in Dehydrogenation of 2-MeTHQ (10)
3.9. X-ray Crystallographic Analyses
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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entry | catalyst | conv. (%) [a, b] | yield (%) [a, b] |
---|---|---|---|
1 | 3a | 35 | 35 |
2 | 3b | 57 | 57 |
3 | 3c | 53 | 53 |
4 | 3d | 55 | 55 |
5 | 3e | 64 | 64 |
entry | catalyst | conv. (%) [a] | yield (%) [a] |
---|---|---|---|
1 | 3a | 19 | 18 |
2 | 3b | 49 | 49 |
3 | 3e | 57 | 57 |
entry | catalyst | yield (%) [a] |
---|---|---|
1 | 3a | 41 |
2 | 3b | 46 |
3 | 3e | 48 |
entry | catalyst | conv. (%) [a] | yield (%) [a] |
---|---|---|---|
1 | 3a | 55 | 55 |
2 | 3b | 91 | 91 |
3 | 3c | 83 | 83 |
4 | 3d | 62 | 62 |
5 | 3e | 99 | 99 |
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Jeong, J.; Shimbayashi, T.; Fujita, K.-i. Effect of a Substituent in Cyclopentadienyl Ligand on Iridium-Catalyzed Acceptorless Dehydrogenation of Alcohols and 2-Methyl-1,2,3,4-tetrahydroquinoline. Catalysts 2019, 9, 846. https://doi.org/10.3390/catal9100846
Jeong J, Shimbayashi T, Fujita K-i. Effect of a Substituent in Cyclopentadienyl Ligand on Iridium-Catalyzed Acceptorless Dehydrogenation of Alcohols and 2-Methyl-1,2,3,4-tetrahydroquinoline. Catalysts. 2019; 9(10):846. https://doi.org/10.3390/catal9100846
Chicago/Turabian StyleJeong, Jaeyoung, Takuya Shimbayashi, and Ken-ichi Fujita. 2019. "Effect of a Substituent in Cyclopentadienyl Ligand on Iridium-Catalyzed Acceptorless Dehydrogenation of Alcohols and 2-Methyl-1,2,3,4-tetrahydroquinoline" Catalysts 9, no. 10: 846. https://doi.org/10.3390/catal9100846