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Lewis-Acid-Catalyzed (3+2)-Cycloadditions of Donor-Acceptor Cyclopropanes with Thioketenes.

ABSTRACT: The reactivity of donor-acceptor (D-A) cyclopropanes towards thioketenes was investigated. In a (3+2)-cycloaddition using Sc(OTf)₃ as a Lewis acidic catalyst, the corresponding exocyclic thioenol ethers (2-methylidene tetrahydrothiophenes) were formed in moderate to good yields. Unsymmetrical thioketenes provided E/Z mixtures at the double bond, with the Z isomer being preferred.

SUBMITTER: Mloston G

PROVIDER: S-EPMC9290834 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Lewis-Acid-Catalyzed (3+2)-Cycloadditions of Donor-Acceptor Cyclopropanes with Thioketenes.

Mlostoń Grzegorz G Kowalczyk Mateusz M Augustin André U AU Jones Peter G PG Werz Daniel B DB

European journal of organic chemistry 20210825 46

The reactivity of donor-acceptor (D-A) cyclopropanes towards thioketenes was investigated. In a (3+2)-cycloaddition using Sc(OTf)3 as a Lewis acidic catalyst, the corresponding exocyclic thioenol ethers (2-methylidene tetrahydrothiophenes) were formed in moderate to good yields. Unsymmetrical thioketenes provided E/Z mixtures at the double bond, with the Z isomer being preferred. ...[more]

PMID: 35875264

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