Regioselective Monobromination of Phenols with KBr and ZnAl–BrO3−–Layered Double Hydroxides
Abstract
:1. Introduction
2. Results
3. Discussion
4. Materials and Methods
4.1. General Information
4.2. General Procedure for the Bromination
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample Availability: Samples of the compounds are not available from the authors. |
Entry | Oxidant (equiv.) | Bromide (equiv.) | Solvent 2 | Temperature | Yield 3 |
---|---|---|---|---|---|
1 | ZnAl-BrO3--LDHs (0.2) | LiBr (1.4) | AcOH | 25 °C | 71 |
2 | ZnAl-BrO3--LDHs (0.2) | LiBr (1.2) | AcOH | 25 °C | 73 |
3 | ZnAl-BrO3--LDHs (0.2) | LiBr (1.0) | AcOH | 25 °C | 76 |
4 | ZnAl-BrO3--LDHs (0.2) | LiBr (0.8) | AcOH | 25 °C | 68 |
5 | ZnAl-BrO3--LDHs (0.2) | NaBr (1.0) | AcOH | 25 °C | 80 |
6 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | AcOH | 25 °C | 83 |
7 | ZnAl-BrO3--LDHs (0.2) | ZnBr2 (0.5) | AcOH | 25 °C | 73 |
8 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | MeOH | 25 °C | - |
9 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | EtOH | 25 °C | - |
10 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | DCM | 25 °C | - |
11 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | EA | 25 °C | - |
12 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | AcOH/H2O | 25 °C | 86 |
13 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | AcOH/H2O | 30 °C | 85 |
14 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | AcOH/H2O | 35 °C | 91 |
15 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | AcOH/H2O | 40 °C | 81 |
16 | ZnAl-BrO3--LDHs (0.2) | KBr (1.0) | AcOH/H2O | 45 °C | 77 |
17 | ZnAl-BrO3--LDHs (0.4) | KBr (2.0) | AcOH/H2O | 35°C | 76 (17) |
18 | KBrO3 (0.4) | KBr (2.0) | AcOH/H2O | 35 °C | 22 (61) |
19 | KBrO3 (0.2) | KBr (1.0) | AcOH/H2O | 35 °C | 35 (28) |
20 | - | KBr (1.0) | AcOH/H2O | 35 °C | - |
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Wang, L.; Feng, C.; Zhang, Y.; Hu, J. Regioselective Monobromination of Phenols with KBr and ZnAl–BrO3−–Layered Double Hydroxides. Molecules 2020, 25, 914. https://doi.org/10.3390/molecules25040914
Wang L, Feng C, Zhang Y, Hu J. Regioselective Monobromination of Phenols with KBr and ZnAl–BrO3−–Layered Double Hydroxides. Molecules. 2020; 25(4):914. https://doi.org/10.3390/molecules25040914
Chicago/Turabian StyleWang, Ligeng, Chun Feng, Yan Zhang, and Jun Hu. 2020. "Regioselective Monobromination of Phenols with KBr and ZnAl–BrO3−–Layered Double Hydroxides" Molecules 25, no. 4: 914. https://doi.org/10.3390/molecules25040914
APA StyleWang, L., Feng, C., Zhang, Y., & Hu, J. (2020). Regioselective Monobromination of Phenols with KBr and ZnAl–BrO3−–Layered Double Hydroxides. Molecules, 25(4), 914. https://doi.org/10.3390/molecules25040914