Preparation of Second Generation Ionic Liquids by Efficient Solvent-Free Alkylation of N-Heterocycles with Chloroalkanes
Abstract
:Introduction
Results and Discussion
Entry | Anion source | Irradiation time (min) | MW power (W) | US power (W) | Temperature (°C)* | Yield (%) |
---|---|---|---|---|---|---|
1a | KPF6 | **10/20 | 90 | 40 | 120/140 | 98 |
1b | KPF6 | 60 | 60 | - | 140 | 88 |
1c | KPF6 | 60 (oil bath) | - | 40 | 140 | 62 |
1d | KPF6 | 60 (oil bath) | - | - | 140 | 47 |
1e | KPF6 | 240 (oil bath) | - | - | 140 | 84 |
2 | KBF4 | **10/20 | 75 | 40 | 120/140 | 95 |
3 | KOTf | **10/45 | 85 | 45 | 120/140 | 65 |
4 | LiN(Tf)2 | **10/90 | 110 | 45 | 120/140 | 72 |
Entry | Heterocycle* | Alkyl halide | Irradiation time (min) (1 or 2 steps) | MW power (W) | US power (W) | Temperature (°C) | Yield (%) |
---|---|---|---|---|---|---|---|
1 | 1-mim | 1-ClC4 | **60/240 | - | - | 140/180 | 95 |
2 | 1-mim | 1-ClC4 | 150 | 120*** | 30 | 75 | <5 |
3 | 1-mim | 1-ClC4 | 10/30 | 85 | - | 120/180 | 98 |
4 | pyr | 1-ClC8 | **60/240 | - | - | 140/180 | 80 |
5 | pyr | 1-ClC8 | 180 | 60*** | 25 | 100 | <5 |
6 | pyr | 1-ClC8 | 10/30 | 85 | - | 120/180 | 85 |
7 | 1-mpyr | 1-ClC8 | **60/240 | - | - | 140/180 | 88 |
8 | 1-mpyr | 1-ClC8 | 10/60 | 40 | - | 80/120 | 0 |
9 | 1-mpyr | 1-ClC8 | 15/50 | 80 | - | 120/160 | 20 |
10 | 1-mpyr | 1-ClC8 | 15/50 | 90 | - | 120/180 | 99 |
Entry | Heterocycle** | Alkyl halide | Anion source | Irradiation steps (min) | MW power (W) | Yield (%) |
---|---|---|---|---|---|---|
1 | 1-mim | 1-ClC4 | KPF6 | 15/30 | 60 | 90 |
2 | 1-mim | 1-ClC4 | KBF4 | 10/30 | 55 | 72 |
3 | 1-mim | 1-ClC4 | KOTf | 15/40 | 65 | 75 |
4 | 1-mim | 1-ClC4 | LiN(Tf)2 | 10/30 | 65 | 62 |
5 | pyr | 1-ClC8 | KPF6 | 15/50 | 65 | 83 |
6 | pyr | 1-ClC8 | KBF4 | 10/40 | 60 | 68 |
7 | pyr | 1-ClC8 | KOTf | 10/50 | 55 | 60 |
8 | pyr | 1-ClC8 | LiN(Tf)2 | 15/50 | 65 | traces |
9 | 1-mpyr | 1-ClC8 | KPF6 | 15/35 | 95 | 85 |
10 | 1-mpyr | 1-ClC8 | KBF4 | 10/45 | 113 | 81 |
11 | 1-mpyr | 1-ClC8 | KOTf | 10/45 | 104 | 79 |
Conclusions
Experimental
General
General procedure
Acknowledgements
References
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Cravotto, G.; Gaudino, E.C.; Boffa, L.; Lévêque, J.-M.; Estager, J.; Bonrath, W. Preparation of Second Generation Ionic Liquids by Efficient Solvent-Free Alkylation of N-Heterocycles with Chloroalkanes. Molecules 2008, 13, 149-156. https://doi.org/10.3390/molecules13010149
Cravotto G, Gaudino EC, Boffa L, Lévêque J-M, Estager J, Bonrath W. Preparation of Second Generation Ionic Liquids by Efficient Solvent-Free Alkylation of N-Heterocycles with Chloroalkanes. Molecules. 2008; 13(1):149-156. https://doi.org/10.3390/molecules13010149
Chicago/Turabian StyleCravotto, Giancarlo, Emanuela Calcio Gaudino, Luisa Boffa, Jean-Marc Lévêque, Julien Estager, and Werner Bonrath. 2008. "Preparation of Second Generation Ionic Liquids by Efficient Solvent-Free Alkylation of N-Heterocycles with Chloroalkanes" Molecules 13, no. 1: 149-156. https://doi.org/10.3390/molecules13010149
APA StyleCravotto, G., Gaudino, E. C., Boffa, L., Lévêque, J.-M., Estager, J., & Bonrath, W. (2008). Preparation of Second Generation Ionic Liquids by Efficient Solvent-Free Alkylation of N-Heterocycles with Chloroalkanes. Molecules, 13(1), 149-156. https://doi.org/10.3390/molecules13010149