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New reductive rearrangement of N-arylindoles triggered by the Grubbs-Stoltz reagent Et₃SiH/KO ^t Bu.

ABSTRACT: N-Arylindoles are transformed into dihydroacridines in a new type of rearrangement, through heating with triethylsilane and potassium tert-butoxide. Studies indicate that the pathway involves (i) the formation of indole radical anions followed by fragmentation of the indole C2-N bond, and (ii) a ring-closing reaction that follows a potassium-ion dependent hydrogen atom transfer step. Unexpected behaviors of 'radical-trap' substrates prove very helpful in framing the proposed mechanism.

SUBMITTER: Smith AJ

PROVIDER: S-EPMC8152433 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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New reductive rearrangement of N-arylindoles triggered by the Grubbs-Stoltz reagent Et3SiH/KO t Bu.

Smith Andrew J AJ Dimitrova Daniela D Arokianathar Jude N JN Kolodziejczak Krystian K Young Allan A Allison Mark M Poole Darren L DL Leach Stuart G SG Parkinson John A JA Tuttle Tell T Murphy John A JA

Chemical science 20200311 14

N-Arylindoles are transformed into dihydroacridines in a new type of rearrangement, through heating with triethylsilane and potassium tert-butoxide. Studies indicate that the pathway involves (i) the formation of indole radical anions followed by fragmentation of the indole C2-N bond, and (ii) a ring-closing reaction that follows a potassium-ion dependent hydrogen atom transfer step. Unexpected behaviors of 'radical-trap' substrates prove very helpful in framing the proposed mechan ...[more]

PMID: 34094060

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