Stereoselective Reduction of Imines with Trichlorosilane Using Solid-Supported Chiral Picolinamides
Abstract
:1. Introduction
2. Results and Discussion
2.1. Catalyst Synthesis
2.2. Stereoselective Reduction of Imines with HSiCl3 in Batch
2.3. Continuous Flow Reaction
3. Materials and Methods
3.1. General Information
3.2. Catalysts Synthesis
3.3. Stereoselective Reduction of Imines
3.4. Product Characterization
4. Conclusions
Supplementary Materials
Acknowledgments
Author Contributions
Conflicts of Interest
References and Notes
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Entry 1 | Catalyst | Yield (%) 2 | ee (%) 3 |
---|---|---|---|
1 | A | 64 | 30 (S) |
2 | B | 95 | 62 (S) |
3 | C | 95 | 23 (S) |
4 | D | 98 | 90 (R) |
5 4 | D | 95 | 91 (R) |
6 5 | D | 95 | 79 (R) |
7 | E | 95 | 63 (S) |
Entry 1 | R | PG | Yield (%) 2 | ee (%) 3 |
---|---|---|---|---|
1 | 6b: 4-NO2-C6H4- | PMP | 93 | 85 |
2 | 6c: 4-F-C6H4- | PMP | 98 | 87 |
3 | 6d: 4-CF3-C6H4- | PMP | 97 | 84 |
4 | 6e: Naphtyl | Ph | 96 | 85 |
Entry | Running Time (min) | Yield (%) 1 | ee (%) 2 |
---|---|---|---|
1 | 0–50 | 98 | 47 |
3 | 50–75 | 98 | 44 |
4 | 75–100 | 93 | 30 |
5 | 100–125 | 93 | 25 |
6 | 125–150 | 87 | 22 |
7 | 150–175 | 86 | 20 |
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Fernandes, S.D.; Porta, R.; Barrulas, P.C.; Puglisi, A.; Burke, A.J.; Benaglia, M. Stereoselective Reduction of Imines with Trichlorosilane Using Solid-Supported Chiral Picolinamides. Molecules 2016, 21, 1182. https://doi.org/10.3390/molecules21091182
Fernandes SD, Porta R, Barrulas PC, Puglisi A, Burke AJ, Benaglia M. Stereoselective Reduction of Imines with Trichlorosilane Using Solid-Supported Chiral Picolinamides. Molecules. 2016; 21(9):1182. https://doi.org/10.3390/molecules21091182
Chicago/Turabian StyleFernandes, Sílvia D., Riccardo Porta, Pedro C. Barrulas, Alessandra Puglisi, Anthony J. Burke, and Maurizio Benaglia. 2016. "Stereoselective Reduction of Imines with Trichlorosilane Using Solid-Supported Chiral Picolinamides" Molecules 21, no. 9: 1182. https://doi.org/10.3390/molecules21091182