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An umpolung reaction of α-iminothioesters possessing a cyclopropyl group.

ABSTRACT: An umpolung N-alkylation reaction of α-cyclopropyl α-iminothioesters with diethylaluminum chloride or ethylmagnesium bromide affords the corresponding N-ethylated α-aminothioesters in good yields. Subsequent oxidation and reaction of the N-ethylated product with a thiolate or a chloride anion proceed effectively to give the ring-opened products in good yields. In contrast, relatively "hard" nucleophiles did not give the ring-opened products but gave the addition products to the iminium carbon.

SUBMITTER: Shimizu M

PROVIDER: S-EPMC9050218 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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An umpolung reaction of α-iminothioesters possessing a cyclopropyl group.

Shimizu Makoto M Morimoto Takayoshi T Yanagi Yusuke Y Mizota Isao I Zhu Yusong Y

RSC advances 20200310 17

An umpolung N-alkylation reaction of α-cyclopropyl α-iminothioesters with diethylaluminum chloride or ethylmagnesium bromide affords the corresponding N-ethylated α-aminothioesters in good yields. Subsequent oxidation and reaction of the N-ethylated product with a thiolate or a chloride anion proceed effectively to give the ring-opened products in good yields. In contrast, relatively "hard" nucleophiles did not give the ring-opened products but gave the addition products to ...[more]

PMID: 35498585

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