Enantioselective conjugate addition of catalytically generated zinc homoenolate
We report herein an enantioselective conjugate addition reaction of a zinc homoenolate, catalytically generated via ring opening of a cyclopropanol, to an α,β-unsaturated ketone. The reaction is promoted by a zinc aminoalkoxide catalyst generated from Et2Zn and a chiral β-amino alcohol to afford 1,6...
| Main Authors: | , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2022
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| Online Access: | https://hdl.handle.net/10356/159329 |
| _version_ | 1826128343967203328 |
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| author | Sekiguchi, Yoshiya Yoshikai, Naohiko |
| author2 | School of Physical and Mathematical Sciences |
| author_facet | School of Physical and Mathematical Sciences Sekiguchi, Yoshiya Yoshikai, Naohiko |
| author_sort | Sekiguchi, Yoshiya |
| collection | NTU |
| description | We report herein an enantioselective conjugate addition reaction of a zinc homoenolate, catalytically generated via ring opening of a cyclopropanol, to an α,β-unsaturated ketone. The reaction is promoted by a zinc aminoalkoxide catalyst generated from Et2Zn and a chiral β-amino alcohol to afford 1,6-diketones, which undergo, upon heating, intramolecular aldol condensation to furnish highly substituted cyclopentene derivatives with good to high enantioselectivities. The reaction has proved applicable to various 1-substituted cyclopropanols as well as chalcones and related enones. The chiral amino alcohol has proved to enable ligand-accelerated catalysis of the homoenolate generation and its conjugate addition. Positive nonlinear effects and lower reactivity of a racemic catalyst have been observed, which can be attributed to a stable and inactive heterochiral zinc aminoalkoxide dimer. |
| first_indexed | 2024-10-01T07:23:27Z |
| format | Journal Article |
| id | ntu-10356/159329 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T07:23:27Z |
| publishDate | 2022 |
| record_format | dspace |
| spelling | ntu-10356/1593292022-06-14T05:51:24Z Enantioselective conjugate addition of catalytically generated zinc homoenolate Sekiguchi, Yoshiya Yoshikai, Naohiko School of Physical and Mathematical Sciences Science::Chemistry Addition Reactions Zinc Compounds We report herein an enantioselective conjugate addition reaction of a zinc homoenolate, catalytically generated via ring opening of a cyclopropanol, to an α,β-unsaturated ketone. The reaction is promoted by a zinc aminoalkoxide catalyst generated from Et2Zn and a chiral β-amino alcohol to afford 1,6-diketones, which undergo, upon heating, intramolecular aldol condensation to furnish highly substituted cyclopentene derivatives with good to high enantioselectivities. The reaction has proved applicable to various 1-substituted cyclopropanols as well as chalcones and related enones. The chiral amino alcohol has proved to enable ligand-accelerated catalysis of the homoenolate generation and its conjugate addition. Positive nonlinear effects and lower reactivity of a racemic catalyst have been observed, which can be attributed to a stable and inactive heterochiral zinc aminoalkoxide dimer. Ministry of Education (MOE) Nanyang Technological University This work was supported by the Ministry of Education (Singapore) and Nanyang Technological University (MOE2016-T2-2-043 and RG101/19). 2022-06-14T05:51:24Z 2022-06-14T05:51:24Z 2021 Journal Article Sekiguchi, Y. & Yoshikai, N. (2021). Enantioselective conjugate addition of catalytically generated zinc homoenolate. Journal of the American Chemical Society, 143(12), 4775-4781. https://dx.doi.org/10.1021/jacs.1c00869 0002-7863 https://hdl.handle.net/10356/159329 10.1021/jacs.1c00869 33724809 2-s2.0-85103495095 12 143 4775 4781 en MOE2016-T2-2-043 RG101/19 Journal of the American Chemical Society © 2021 American Chemical Society. All rights reserved. |
| spellingShingle | Science::Chemistry Addition Reactions Zinc Compounds Sekiguchi, Yoshiya Yoshikai, Naohiko Enantioselective conjugate addition of catalytically generated zinc homoenolate |
| title | Enantioselective conjugate addition of catalytically generated zinc homoenolate |
| title_full | Enantioselective conjugate addition of catalytically generated zinc homoenolate |
| title_fullStr | Enantioselective conjugate addition of catalytically generated zinc homoenolate |
| title_full_unstemmed | Enantioselective conjugate addition of catalytically generated zinc homoenolate |
| title_short | Enantioselective conjugate addition of catalytically generated zinc homoenolate |
| title_sort | enantioselective conjugate addition of catalytically generated zinc homoenolate |
| topic | Science::Chemistry Addition Reactions Zinc Compounds |
| url | https://hdl.handle.net/10356/159329 |
| work_keys_str_mv | AT sekiguchiyoshiya enantioselectiveconjugateadditionofcatalyticallygeneratedzinchomoenolate AT yoshikainaohiko enantioselectiveconjugateadditionofcatalyticallygeneratedzinchomoenolate |