Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives through a Combination of 8-Aminoquinoline Directed C–H Arylation and Transamidation Chemistry
Abstract
1. Introduction
2. Results
3. Discussion
4. Materials and Methods
4.1. General Procedure for the C–H Arylation of Substrates 1a–e
4.2. General Procedure C: Two-Step One-Pot Transamidation of C–H Arylation Products with Different Amines
4.2.1. Boc Activation
4.2.2. Aminolysis
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
References and Notes
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Sample Availability: Samples of all the reported compounds can be made available from the authors upon request. |
Entry | Additive (equiv.) | Solvent | Temp (°C) | Time (h) | Yield (%) |
---|---|---|---|---|---|
1 | none | toluene | 110 | 7 | 46 |
2 | none | toluene | 110 | 16 | 65 |
3 | none | toluene | 120 | 7 | 30 |
4 | (BnO)2PO2H (0.2) | toluene | 110 | 7 | 28 |
5 | PivOH (0.2) | toluene | 110 | 7 | 61 |
6 | PivOH (0.5) | toluene | 110 | 7 | 48 |
7 | PivOH (1.0) | toluene | 110 | 7 | 17 |
8 | NaOAc (0.5) | toluene | 110 | 7 | 62 |
9 | NaOAc (1.0) | toluene | 110 | 7 | 78 |
10 | NaOAc (2.0) | toluene | 110 | 7 | 70 |
11 | PivOH+NaOAc (0.2 + 1.0) | toluene | 110 | 7 | 56 |
12 | NaOAc (1.0) | t-amyl OH | 110 | 7 | 91 |
13 | NaOAc (1.0) | MeTHF | 110 | 7 | 81 |
14 | NaOAc (1.0) | CPME | 110 | 7 | 93 |
15 | NaOAc (1.0) | DCE | 110 | 7 | 69 |
16 | NaOAc (1.0) | MeCN | 110 | 7 | 18 |
17 [b] | NaOAc (1.0) | CPME | 110 | 15 | 80 |
18 [b,c] | NaOAc (1.0) | CPME | 110 | 15 | 73 |
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Oschmann, M.; Johansson Holm, L.; Pourghasemi-Lati, M.; Verho, O. Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives through a Combination of 8-Aminoquinoline Directed C–H Arylation and Transamidation Chemistry. Molecules 2020, 25, 361. https://doi.org/10.3390/molecules25020361
Oschmann M, Johansson Holm L, Pourghasemi-Lati M, Verho O. Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives through a Combination of 8-Aminoquinoline Directed C–H Arylation and Transamidation Chemistry. Molecules. 2020; 25(2):361. https://doi.org/10.3390/molecules25020361
Chicago/Turabian StyleOschmann, Michael, Linus Johansson Holm, Monireh Pourghasemi-Lati, and Oscar Verho. 2020. "Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives through a Combination of 8-Aminoquinoline Directed C–H Arylation and Transamidation Chemistry" Molecules 25, no. 2: 361. https://doi.org/10.3390/molecules25020361
APA StyleOschmann, M., Johansson Holm, L., Pourghasemi-Lati, M., & Verho, O. (2020). Synthesis of Elaborate Benzofuran-2-Carboxamide Derivatives through a Combination of 8-Aminoquinoline Directed C–H Arylation and Transamidation Chemistry. Molecules, 25(2), 361. https://doi.org/10.3390/molecules25020361