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Hilton TA, Leach AG, McKay AP, Watson AJB. Accessing Rare α-Heterocyclic Aziridines via Brønsted Acid-catalyzed Michael Addition/Annulation: Scope, Limitations, and Mechanism. Chemistry 2024; 30:e202303993. [PMID: 38315627 DOI: 10.1002/chem.202303993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/05/2024] [Accepted: 02/05/2024] [Indexed: 02/07/2024]
Abstract
We report an approach to the diastereoselective synthesis of 1,2-disubstituted heterocyclic aziridines. A Brønsted acid-catalyzed conjugate addition of anilines to trisubstituted heterocyclic chloroalkenes provides an intermediate 1,2-chloroamine. Diastereocontrol was found to vary significantly with solvent selection, with computational modelling confirming selective, spontaneous fragmentation in the presence of trace acids, proceeding through a pseudo-cyclic, protonated intermediate and transition state. These chloroamines can then be converted to the aziridine by treatment with LiHMDS with high stereochemical fidelity. This solvent-induced stereochemical enrichment thereby enables an efficient route to rare cis-aziridines with high dr. The scope, limitations, and mechanistic origins of selectivity are also presented.
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Affiliation(s)
- Timothy A Hilton
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, U.K
| | - Andrew G Leach
- School of Health Sciences, University of Manchester, Oxford Road, Manchester, M13 9PL, U.K
| | - Aidan P McKay
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, U.K
| | - Allan J B Watson
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, U.K
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Zhang Q, Duan Y, Guo H, Yang H, Zhai J, Li T, Wang Z, Lu X, Wang Y, Yin Y. Bi(OTf) 3 -catalyed One-pot Synthesis of α-Halo-β-amino Ketones and Acyl Aziridines from 3-Aryl Propargyl Alcohols. Chem Asian J 2021; 16:1832-1838. [PMID: 34002537 DOI: 10.1002/asia.202100368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/12/2021] [Indexed: 11/05/2022]
Abstract
A Bi(OTf)3 -catalyed reaction of 3-aryl propargyl alcohols with sulfonamide and halogen source was firstly investigated, which provided a facile route for the synthesis of a large variety of α-halo-β-amino ketones. The key intermediates, β-amino ketones, were obtained through tandem Meyer-Schuster rearrangement reaction of propargyl alcohols and intermolecular Michael addition of α, β-unsaturated ketones and sulfonamide. Then the in situ generated α-halo-β-amino ketones underwent the base-promoted intramolecular cyclization to give diverse acyl aziridines in a one-pot fashion. These transformations are reliable on a large scale. The high yields and convenient experimental operations make it a valuable method for the construction of α-halo-β-amino ketones and acyl aziridine derivatives.
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Affiliation(s)
- Qinglin Zhang
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Yongbin Duan
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Huifeng Guo
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Hong Yang
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Jiulong Zhai
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Tiantian Li
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Zhihai Wang
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Xiaolei Lu
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Yan Wang
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China
| | - Yan Yin
- Department of Chemical and Environmental Engineering, Shanghai Institute of Technology, 201418, 100 Hai Quan Rd., Shanghai, P. R. China.,Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University, 200092, 1239 Si Ping Rd, Shanghai, P. R. China
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