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Efficient Access to Chiral Trisubstituted Aziridines via Catalytic Enantioselective Aza-Darzens Reactions.

ABSTRACT: Herein, we report a Zn-ProPhenol catalyzed aza-Darzens reaction using chlorinated aromatic ketones as nucleophilic partners for the efficient and enantioselective construction of complex trisubstituted aziridines. The ?-chloro-?-aminoketone intermediates featuring a chlorinated tetrasubstituted stereocenter can be isolated in high yields and selectivities for further derivatization. Alternatively, they can be directly transformed to the corresponding aziridines in a one-pot fashion. Of note, the reaction can be run on gram-scale with low catalyst loading without impacting its efficiency. Moreover, this methodology was extended to ?-bromoketones which are scarcely used in enantioselective catalysis because of their sensitivity and lack of accessibility.

SUBMITTER: Trost BM

PROVIDER: S-EPMC5530870 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Efficient Access to Chiral Trisubstituted Aziridines via Catalytic Enantioselective Aza-Darzens Reactions.

Trost Barry M BM Saget Tanguy T Saget Tanguy T Hung Chao-I Joey CJ

Angewandte Chemie (International ed. in English) 20170123 9

Herein, we report a Zn-ProPhenol catalyzed aza-Darzens reaction using chlorinated aromatic ketones as nucleophilic partners for the efficient and enantioselective construction of complex trisubstituted aziridines. The α-chloro-β-aminoketone intermediates featuring a chlorinated tetrasubstituted stereocenter can be isolated in high yields and selectivities for further derivatization. Alternatively, they can be directly transformed to the corresponding aziridines in a one-pot fashion. Of note, the ...[more]

PMID: 28111864

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