A Lewis Acid-Promoted Michael Addition and Ring-Expansion Cascade for the Construction of Nitrogen-Containing Medium-Sized Rings
Abstract
:1. Introduction
2. Results and Discussion
3. Materials and Methods
3.1. General Procedure for the Synthesis of 3
3.2. General Procedure for the Synthesis of 6
3.3. General Procedure for the Synthesis of 7
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 a | Solvent | Base | Lewis Acid | Yield (%) b |
---|---|---|---|---|
1 | CH2Cl2 | Et3N | 16 | |
2 e | CH2Cl2 | DIPEA | 11 | |
3 f | CH2Cl2 | DMAP | 17 | |
4 g | CH2Cl2 | DBN | NR | |
5 | CH2Cl2 | Cs2CO3 | 17 | |
6 | CH2Cl2 | NaHCO3 | 26 | |
7 | CH2Cl2 | K2CO3 | 27 | |
8 | CH2Cl2 | KOtBu | trace | |
9 | CH2Cl2 | KOH | trace | |
10 | CH2Cl2 | K2CO3 | Mg(OTf)2 | 54 |
11 | CH2Cl2 | K2CO3 | Sc(OTf)2 | trace |
12 | CH2Cl2 | K2CO3 | Zn(OTf)2 | 41 |
13 | CH2Cl2 | K2CO3 | Cu(OTf)2 | 11 |
14 | THF | K2CO3 | Mg(OTf)2 | 57 |
15 h | DCE | K2CO3 | Mg(OTf)2 | 63 |
16 | MeCN | K2CO3 | Mg(OTf)2 | 46 |
17 | Toluene | K2CO3 | Mg(OTf)2 | 18 |
18 i | DCE | K2CO3 | Mg(OTf)2 | 78 |
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Wang, J.; Li, J.; Zhao, C. A Lewis Acid-Promoted Michael Addition and Ring-Expansion Cascade for the Construction of Nitrogen-Containing Medium-Sized Rings. Molecules 2023, 28, 1650. https://doi.org/10.3390/molecules28041650
Wang J, Li J, Zhao C. A Lewis Acid-Promoted Michael Addition and Ring-Expansion Cascade for the Construction of Nitrogen-Containing Medium-Sized Rings. Molecules. 2023; 28(4):1650. https://doi.org/10.3390/molecules28041650
Chicago/Turabian StyleWang, Jiaming, Jia Li, and Changgui Zhao. 2023. "A Lewis Acid-Promoted Michael Addition and Ring-Expansion Cascade for the Construction of Nitrogen-Containing Medium-Sized Rings" Molecules 28, no. 4: 1650. https://doi.org/10.3390/molecules28041650
APA StyleWang, J., Li, J., & Zhao, C. (2023). A Lewis Acid-Promoted Michael Addition and Ring-Expansion Cascade for the Construction of Nitrogen-Containing Medium-Sized Rings. Molecules, 28(4), 1650. https://doi.org/10.3390/molecules28041650