Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng
The Lewis acid, AlBr3, was found to effectively catalyse the Diels-Alder reaction between cinnamoyl dienophile, trans-chalcone and terpene diene, (E)-ocimene to give the cycloadduct product of [(1RS,2SR,6RS)-3-methyl-2-(3-methylbut-2-en-1-yl)-6-phenylcyclohex-3-en-1-yl](phenyl)methanone in high yiel...
Saved in:
| Main Author: | |
|---|---|
| Format: | Thesis |
| Published: |
2024
|
| Subjects: | |
| Online Access: | http://studentsrepo.um.edu.my/15710/1/Thy_Chun_Keng.pdf http://studentsrepo.um.edu.my/15710/2/Thy_Chun_Keng.pdf http://studentsrepo.um.edu.my/15710/ |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1839752391585431552 |
|---|---|
| author | Thy , Chun Keng |
| author_facet | Thy , Chun Keng |
| author_sort | Thy , Chun Keng |
| building | UM Library |
| collection | Institutional Repository |
| content_provider | Universiti Malaya |
| content_source | UM Student Repository |
| continent | Asia |
| country | Malaysia |
| description | The Lewis acid, AlBr3, was found to effectively catalyse the Diels-Alder reaction between cinnamoyl dienophile, trans-chalcone and terpene diene, (E)-ocimene to give the cycloadduct product of [(1RS,2SR,6RS)-3-methyl-2-(3-methylbut-2-en-1-yl)-6-phenylcyclohex-3-en-1-yl](phenyl)methanone in high yield (72%) and with excellent regio- (100:0) and diastereoselectivity (95:5). The effectiveness of the AlBr3 towards Diels-Alder reactions between various dienophiles and dienes was also evaluated. The acyclic dienes such as isoprene, 2,3-dimethylbutadiene and myrcene underwent Diels-Alder reaction with trans-chalcone, affording the corresponding adducts in relatively good yields (73-82%) and with excellent regioselectivity (90:10). A chiral titanium complex with 2 equivalents of FMOC-L-Phe-OH exhibited a significant enantioselectivity (61% ee) in the study of asymmetric Diels-Alder reaction of trans-chalcone and isoprene but unfortunately producing low yield (21%). A series of (±)-panduratin A derivatives were prepared by using AlBr3 as catalyst. Eighteen (±)-panduratin A derivatives were successfully synthesised with yields between 9 to 71%. The natural products, fislatifolione, isofislatifolione, fislatifolic acid, panduratins H and I were synthesised via thermal, catalyst and chiral complex-induced Diels-Alder reactions. The thermal-induced Diels-Alder reaction afforded the natural products in moderate yields (28-39%) and with moderate regioselectivities (67:33 to 77:23), but only fislatifolione and isofislatifolione were successfully synthesised through catalyst and chiral complex-induced Diels-Alder reactions.
|
| format | Thesis |
| id | my.um.stud-15710 |
| institution | Universiti Malaya |
| publishDate | 2024 |
| record_format | eprints |
| spelling | my.um.stud-157102025-07-30T00:00:17Z Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng Thy , Chun Keng Q Science (General) QD Chemistry The Lewis acid, AlBr3, was found to effectively catalyse the Diels-Alder reaction between cinnamoyl dienophile, trans-chalcone and terpene diene, (E)-ocimene to give the cycloadduct product of [(1RS,2SR,6RS)-3-methyl-2-(3-methylbut-2-en-1-yl)-6-phenylcyclohex-3-en-1-yl](phenyl)methanone in high yield (72%) and with excellent regio- (100:0) and diastereoselectivity (95:5). The effectiveness of the AlBr3 towards Diels-Alder reactions between various dienophiles and dienes was also evaluated. The acyclic dienes such as isoprene, 2,3-dimethylbutadiene and myrcene underwent Diels-Alder reaction with trans-chalcone, affording the corresponding adducts in relatively good yields (73-82%) and with excellent regioselectivity (90:10). A chiral titanium complex with 2 equivalents of FMOC-L-Phe-OH exhibited a significant enantioselectivity (61% ee) in the study of asymmetric Diels-Alder reaction of trans-chalcone and isoprene but unfortunately producing low yield (21%). A series of (±)-panduratin A derivatives were prepared by using AlBr3 as catalyst. Eighteen (±)-panduratin A derivatives were successfully synthesised with yields between 9 to 71%. The natural products, fislatifolione, isofislatifolione, fislatifolic acid, panduratins H and I were synthesised via thermal, catalyst and chiral complex-induced Diels-Alder reactions. The thermal-induced Diels-Alder reaction afforded the natural products in moderate yields (28-39%) and with moderate regioselectivities (67:33 to 77:23), but only fislatifolione and isofislatifolione were successfully synthesised through catalyst and chiral complex-induced Diels-Alder reactions. 2024-01 Thesis NonPeerReviewed application/pdf http://studentsrepo.um.edu.my/15710/1/Thy_Chun_Keng.pdf application/pdf http://studentsrepo.um.edu.my/15710/2/Thy_Chun_Keng.pdf Thy , Chun Keng (2024) Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng. PhD thesis, Universiti Malaya. http://studentsrepo.um.edu.my/15710/ |
| spellingShingle | Q Science (General) QD Chemistry Thy , Chun Keng Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng |
| title | Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng |
| title_full | Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng |
| title_fullStr | Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng |
| title_full_unstemmed | Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng |
| title_short | Diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / Thy Chun Keng |
| title_sort | diels-alder reaction of cinnamoyl dienophiles and terpene dienes and its application towards the synthesis of natural products / thy chun keng |
| topic | Q Science (General) QD Chemistry |
| url | http://studentsrepo.um.edu.my/15710/1/Thy_Chun_Keng.pdf http://studentsrepo.um.edu.my/15710/2/Thy_Chun_Keng.pdf http://studentsrepo.um.edu.my/15710/ |
| url_provider | http://studentsrepo.um.edu.my/ |