Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes
Michael addition is an important reaction because it can be used to synthesize a wide range of natural products or complex compounds that exhibit biological activities. In this study, a mirror image of an aldehyde and α,β-unsaturated nitroalkene were reacted in the presence of (<i>R</i>,...
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MDPI AG
2022-01-01
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| Online Access: | https://www.mdpi.com/2073-4344/12/2/121 |
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| author | Jae Ho Shim Seok Hyun Cheun Hyeon Soo Kim Deok-Chan Ha |
| author_facet | Jae Ho Shim Seok Hyun Cheun Hyeon Soo Kim Deok-Chan Ha |
| author_sort | Jae Ho Shim |
| collection | DOAJ |
| description | Michael addition is an important reaction because it can be used to synthesize a wide range of natural products or complex compounds that exhibit biological activities. In this study, a mirror image of an aldehyde and α,β-unsaturated nitroalkene were reacted in the presence of (<i>R</i>,<i>R</i>)-1,2-diphenylethylenediamine (DPEN). Herein, thiourea was introduced as an organic catalyst, and a selective Michael addition reaction was carried out. The primary amine moiety of DPEN reacts with aldehydes to form enamines, which is activated by the hydrogen bond formation between the nitro groups of α,β-unsaturated nitroalkenes and thiourea. Our aim was to obtain an asymmetric Michael product by adding 1,4-enamine to an alkene to form a new carbon–carbon bond. As a result, the primary amine of the chiral diamine was converted to an enamine. The reaction proceeded with a relatively high degree of enantioselectivity, which was achieved using double activation via hydrogen bonding of the nitro group and thiourea. Michael products with a high degree of enantioselectivity (97–99% <i>synee</i>) and diastereoselectivity (<i>syn</i>/<i>anti</i> = 9/1) were obtained in yields ranging from 94–99% depending on the aldehydes. |
| first_indexed | 2024-03-09T22:22:39Z |
| format | Article |
| id | doaj.art-e63bcd5d459a42d7837219f5786de92d |
| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-09T22:22:39Z |
| publishDate | 2022-01-01 |
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| record_format | Article |
| series | Catalysts |
| spelling | doaj.art-e63bcd5d459a42d7837219f5786de92d2023-11-23T19:11:36ZengMDPI AGCatalysts2073-43442022-01-0112212110.3390/catal12020121Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated NitroalkenesJae Ho Shim0Seok Hyun Cheun1Hyeon Soo Kim2Deok-Chan Ha3Department of Anatomy, Korea University College of Medicine, 46, Gaeunsa 2-gil, Seongbuk-gu, Seoul 02842, KoreaDepartment of Chemistry, Korea University, 145 Anam-ro Seongbuk-gu, Seoul 02841, KoreaDepartment of Anatomy, Korea University College of Medicine, 46, Gaeunsa 2-gil, Seongbuk-gu, Seoul 02842, KoreaDepartment of Chemistry, Korea University, 145 Anam-ro Seongbuk-gu, Seoul 02841, KoreaMichael addition is an important reaction because it can be used to synthesize a wide range of natural products or complex compounds that exhibit biological activities. In this study, a mirror image of an aldehyde and α,β-unsaturated nitroalkene were reacted in the presence of (<i>R</i>,<i>R</i>)-1,2-diphenylethylenediamine (DPEN). Herein, thiourea was introduced as an organic catalyst, and a selective Michael addition reaction was carried out. The primary amine moiety of DPEN reacts with aldehydes to form enamines, which is activated by the hydrogen bond formation between the nitro groups of α,β-unsaturated nitroalkenes and thiourea. Our aim was to obtain an asymmetric Michael product by adding 1,4-enamine to an alkene to form a new carbon–carbon bond. As a result, the primary amine of the chiral diamine was converted to an enamine. The reaction proceeded with a relatively high degree of enantioselectivity, which was achieved using double activation via hydrogen bonding of the nitro group and thiourea. Michael products with a high degree of enantioselectivity (97–99% <i>synee</i>) and diastereoselectivity (<i>syn</i>/<i>anti</i> = 9/1) were obtained in yields ranging from 94–99% depending on the aldehydes.https://www.mdpi.com/2073-4344/12/2/121organocatalystenantioselectivityaldehydesthiourea catalystasymmetric synthesisMichael addition |
| spellingShingle | Jae Ho Shim Seok Hyun Cheun Hyeon Soo Kim Deok-Chan Ha Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes Catalysts organocatalyst enantioselectivity aldehydes thiourea catalyst asymmetric synthesis Michael addition |
| title | Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes |
| title_full | Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes |
| title_fullStr | Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes |
| title_full_unstemmed | Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes |
| title_short | Organocatalysis for the Asymmetric Michael Addition of Aldehydes and α,β-Unsaturated Nitroalkenes |
| title_sort | organocatalysis for the asymmetric michael addition of aldehydes and α β unsaturated nitroalkenes |
| topic | organocatalyst enantioselectivity aldehydes thiourea catalyst asymmetric synthesis Michael addition |
| url | https://www.mdpi.com/2073-4344/12/2/121 |
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