Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2
The use of γ-Al2O3 as a heterogeneous catalyst in scCO2, has be successfully applied to the amination of alcohols for the synthesis of N-alkylated heterocycles. The optimal reaction conditions (temperature and substrate flow rate) were determined using an automated self-optimising reactor, resulting...
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| Format: | Article |
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Beilstein-Institut
2017
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| Online Access: | https://eprints.nottingham.ac.uk/41185/ |
| _version_ | 1848796216247189504 |
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| author | Streng, Emelia S. Lee, Darren S. George, Michael W. Poliakoff, Martyn |
| author_facet | Streng, Emelia S. Lee, Darren S. George, Michael W. Poliakoff, Martyn |
| author_sort | Streng, Emelia S. |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | The use of γ-Al2O3 as a heterogeneous catalyst in scCO2, has be successfully applied to the amination of alcohols for the synthesis of N-alkylated heterocycles. The optimal reaction conditions (temperature and substrate flow rate) were determined using an automated self-optimising reactor, resulting in moderate to high yields of the target products. Carrying out the reaction in scCO2 was shown to be beneficial, as higher yields were obtained in the presence of CO2 than in its absence. A surprising discovery is that, in addition to cyclic amines, cyclic ureas and urethanes could be synthesised by incorporation of CO2 from the supercritical solvent into the product. |
| first_indexed | 2025-11-14T19:44:27Z |
| format | Article |
| id | nottingham-41185 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:44:27Z |
| publishDate | 2017 |
| publisher | Beilstein-Institut |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-411852020-05-04T18:34:06Z https://eprints.nottingham.ac.uk/41185/ Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 Streng, Emelia S. Lee, Darren S. George, Michael W. Poliakoff, Martyn The use of γ-Al2O3 as a heterogeneous catalyst in scCO2, has be successfully applied to the amination of alcohols for the synthesis of N-alkylated heterocycles. The optimal reaction conditions (temperature and substrate flow rate) were determined using an automated self-optimising reactor, resulting in moderate to high yields of the target products. Carrying out the reaction in scCO2 was shown to be beneficial, as higher yields were obtained in the presence of CO2 than in its absence. A surprising discovery is that, in addition to cyclic amines, cyclic ureas and urethanes could be synthesised by incorporation of CO2 from the supercritical solvent into the product. Beilstein-Institut 2017-02-21 Article PeerReviewed Streng, Emelia S., Lee, Darren S., George, Michael W. and Poliakoff, Martyn (2017) Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2. Beilstein Journal of Organic Chemistry, 13 . pp. 329-337. ISSN 1860-5397 Continuous flow; heterocycle; N-alkylation; self-optimisation; supercritical CO2 http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-13-36 doi:10.3762/bjoc.13.36 doi:10.3762/bjoc.13.36 |
| spellingShingle | Continuous flow; heterocycle; N-alkylation; self-optimisation; supercritical CO2 Streng, Emelia S. Lee, Darren S. George, Michael W. Poliakoff, Martyn Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 |
| title | Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 |
| title_full | Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 |
| title_fullStr | Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 |
| title_full_unstemmed | Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 |
| title_short | Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2 |
| title_sort | continuous n-alkylation reactions of amino alcohols using γ-al2o3 and supercritical co2: unexpected formation of cyclic ureas and urethanes by reaction with co2 |
| topic | Continuous flow; heterocycle; N-alkylation; self-optimisation; supercritical CO2 |
| url | https://eprints.nottingham.ac.uk/41185/ https://eprints.nottingham.ac.uk/41185/ https://eprints.nottingham.ac.uk/41185/ |