Studies on asymmetric total synthesis of (−)-β-hydrastine via a chiral epoxide ring-opening cascade cyclization strategy
| Autor: | Yongxiang Liu, Tianxiao Wu, Xinjing Song, Jiaxin Meng, Qiaohua Qin, Maosheng Cheng, Yang Zheng, Dongmei Zhao, Jihui Li |
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| Rok vydání: | 2020 |
| Předmět: |
chemistry.chemical_classification
Ketone 010405 organic chemistry Stereochemistry Tetrahydroisoquinoline General Chemical Engineering Enantioselective synthesis Epoxide Total synthesis General Chemistry 010402 general chemistry 01 natural sciences Hydrastine 0104 chemical sciences Phthalide chemistry.chemical_compound chemistry Intramolecular force medicine medicine.drug |
| Zdroj: | RSC Advances. 10:18953-18958 |
| ISSN: | 2046-2069 |
| Popis: | Herein, facile and enantioselective approaches to synthesize the core phthalide tetrahydroisoquinoline scaffold of (−)-β-hydrastine via both a CF3COOH-catalyzed (86% ee) and KHMDS-catalyzed (78% ee) epoxide ring-opening/transesterification cascade cyclization from chiral epoxide under very mild conditions are described. The key elements include a highly enantioselective epoxidation using the Shi ketone catalyst and an intramolecular CF3COOH-catalyzed cascade cyclization in one pot, and a late-stage C-3′ epimerization under MeOK/MeOH conditions as the key steps to achieve the first total synthesis of (−)-β-hydrastine (up to 81% ee). |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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