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Dearomatization of aromatic asmic isocyanides to complex cyclohexadienes.

ABSTRACT: A dearomatization-dislocation-coupling cascade rapidly transforms aromatic isocyanides into highly functionalized cyclohexadienes. The facile cascade installs an exceptional degree of molecular complexity: three carbon-carbon bonds, two quaternary stereocenters, and three orthogonal functionalities, a cyclohexadiene, a nitrile, and an isocyanide. The tolerance of arylisocyanides makes the method among the mildest dearomatizations ever reported, typically occurring within minutes at -78 °C. Experimental and computational analyses implicate an electron transfer-initiated mechanism involving an unprecedented isocyanide rearrangement followed by radical-radical anion coupling. The dearomatization is fast, proceeds via a complex cascade mechanism supported by experimental and computational insight, and provides complex, synthetically valuable cyclohexadienes.

SUBMITTER: Altundas B

PROVIDER: S-EPMC9616822 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Dearomatization of aromatic asmic isocyanides to complex cyclohexadienes.

Altundas Bilal B Alwedi Embarek E Song Zhihui Z Gogoi Achyut Ranjan AR Dykstra Ryan R Gutierrez Osvaldo O Fleming Fraser F FF

Nature communications 20221028 1

A dearomatization-dislocation-coupling cascade rapidly transforms aromatic isocyanides into highly functionalized cyclohexadienes. The facile cascade installs an exceptional degree of molecular complexity: three carbon-carbon bonds, two quaternary stereocenters, and three orthogonal functionalities, a cyclohexadiene, a nitrile, and an isocyanide. The tolerance of arylisocyanides makes the method among the mildest dearomatizations ever reported, typically occurring within minutes at -78 °C. Exper ...[more]

PMID: 36307409

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