Enantioselective Benzylic Hydroxylation of Arylalkanes with H2O2 in Fluorinated Alcohols in the Presence of Chiral Mn Aminopyridine Complexes Научная публикация
Журнал |
ChemCatChem
ISSN: 1867-3880 , E-ISSN: 1867-3899 |
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Вых. Данные | Год: 2018, Том: 10, Номер: 22, Страницы: 5323-5330 Страниц : 9 DOI: 10.1002/cctc.201801476 | ||||||
Ключевые слова | Asymmetric catalysis; C−H hydroxylation; enzyme models; hydrogen-bond donor; hydrogen peroxide; manganese | ||||||
Авторы |
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Организации |
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Информация о финансировании (1)
1 | Федеральное агентство научных организаций России | 0303-2016-0005 |
Реферат:
A series of chiral bioinspired Mn‐aminopyridine complexes of the type [L*MnII(OTf)2] (where L* is 2,2′‐bipyrrolidine derived ligand, bearing trifluoroalkoxy and alkyl substituents) have been tested as catalysts in benzylic C−H hydroxylation of arylalkanes with H2O2 in fluorinated ethanols media. In 2,2,2‐trifuoroethanol, the yield of the target ethylbenzene oxidation product, chiral 1‐phenylethanol, reaches 45 %, which is much better than in the common solvent CH3CN (5‐6 %). The selectivity for 1‐phenylethanol formation increases in the following order: CH3CN<2‐fluoroethanol<2,2‐difluoroethanol<2,2,2‐trifuoroethanol, while 2,2‐difluoroethanol ensures the highest asymmetric induction in this series, affording chiral benzylic alcohols with up to 89 % ee. In trifluoroethanol, the observed primary kH/kD value of 2.3 has been measured for the oxidation of 1‐phenylethanol/α‐D‐1‐phenylethanol, which is similar to that in CH3CN (2.2). At the same time, depending on the solvent, CH3CN or 2,2,2‐trifuoroethanol, the oxidations of 1‐phenylethanol demonstrates drastically different linear free‐energy relationships; possible effect of the hydrogen‐bond donor (HBD) nature of CF3CH2OH is discussed in this context. Noticeably, it has been shown that by switching the absolute chirality ((S,S)− or (R,R)−) of the catalyst, the oxidation of complex substrate of natural origin, estrone acetate, can be diverted to predominant formation of either the tertiary C9‐alcohol or of the C6‐ketone, respectively.
Библиографическая ссылка:
Ottenbacher R.V.
, Talsi E.P.
, Rybalova T.V.
, Bryliakov K.P.
Enantioselective Benzylic Hydroxylation of Arylalkanes with H2O2 in Fluorinated Alcohols in the Presence of Chiral Mn Aminopyridine Complexes
ChemCatChem. 2018. V.10. N22. P.5323-5330. DOI: 10.1002/cctc.201801476 WOS Scopus РИНЦ CAPlus OpenAlex
Enantioselective Benzylic Hydroxylation of Arylalkanes with H2O2 in Fluorinated Alcohols in the Presence of Chiral Mn Aminopyridine Complexes
ChemCatChem. 2018. V.10. N22. P.5323-5330. DOI: 10.1002/cctc.201801476 WOS Scopus РИНЦ CAPlus OpenAlex
Даты:
Поступила в редакцию: | 7 сент. 2018 г. |
Принята к публикации: | 2 окт. 2018 г. |
Опубликована online: | 5 нояб. 2018 г. |
Опубликована в печати: | 22 нояб. 2018 г. |
Идентификаторы БД:
Web of science: | WOS:000451444000027 |
Scopus: | 2-s2.0-85056107536 |
РИНЦ: | 38669445 |
Chemical Abstracts: | 2018:2109781 |
OpenAlex: | W2894655722 |