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Updated: May 6, 2026
Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
In situ assembled boronate ester assisted chiral carboxylic acid catalyzed asymmetric trans-aziridinations
Takuya Hashimoto1, Alberto Osuna Gálvez, Keiji Maruoka
1Department of Chemistry, Graduate School of Science, Kyoto University , Sakyo, Kyoto 606-8502, Japan.
Abstract:
We developed herein a new chiral Brønsted acid catalyst which is composed of two independent organic molecules, a chiral diol, and 2-boronobenzoic acid. In situ formation of a boronate ester was utilized as a key process to generate an active catalyst. This boronate ester assisted chiral carboxylic acid catalyst was successfully applied to the trans-aziridination of N-Boc and N-benzyl imines with N-phenyldiazoacetamide. This is the first catalyst to achieve high enantioselectivities using N-benzyl imines.
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