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Ring-opening hydroarylation of monosubstituted cyclopropanes enabled by hexafluoroisopropanol.

ABSTRACT: Ring-opening hydroarylation of cyclopropanes is typically limited to substrates bearing a donor-acceptor motif. Here, the transformation is achieved for monosubstituted cyclopropanes by using catalytic Brønsted acid in hexafluoroisopropanol (HFIP) solvent, constituting a rare example where such cyclopropanes engage in intermolecular C-C bond formation. Branched products are obtained when electron-rich arylcyclopropanes react with a broad scope of arene nucleophiles in accord with a simple S_N1-type ring-opening mechanism. In contrast, linear products are obtained when cyclopropylketones react with electron-rich arene nucleophiles. In the latter case, mechanistic experiments and DFT-calculations support a homo-conjugate addition pathway.

SUBMITTER: Richmond E

PROVIDER: S-EPMC6115651 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Ring-opening hydroarylation of monosubstituted cyclopropanes enabled by hexafluoroisopropanol.

Richmond Edward E Yi Jing J Vuković Vuk D VD Sajadi Fatima F Rowley Christopher N CN Moran Joseph J

Chemical science 20180628 30

Ring-opening hydroarylation of cyclopropanes is typically limited to substrates bearing a donor-acceptor motif. Here, the transformation is achieved for monosubstituted cyclopropanes by using catalytic Brønsted acid in hexafluoroisopropanol (HFIP) solvent, constituting a rare example where such cyclopropanes engage in intermolecular C-C bond formation. Branched products are obtained when electron-rich arylcyclopropanes react with a broad scope of arene nucleophiles in accord with a simple S<sub> ...[more]

PMID: 30310570

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