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Photochemical Approach to the Cyclohepta[b]indole Scaffold by Annulative Two-Carbon Ring-Expansion.

ABSTRACT: We report on the implementation of the concept of a photochemically elicited two-carbon homologation of a ?-donor-?-acceptor substituted chromophore by triple-bond insertion. Implementing a phenyl connector between the slide-in module and the chromophore enabled the synthesis of cylohepta[b]indole-type building blocks by a metal-free annulative one-pot two-carbon ring expansion of the five-membered chromophore. Post-irradiative structural elaboration provided founding members of the indolo[2,3-d]tropone family of compounds. Control experiments in combination with computational chemistry on this multibond reorganization process founded the basis for a mechanistic hypothesis.

SUBMITTER: Tymann DC

PROVIDER: S-EPMC7540574 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Photochemical Approach to the Cyclohepta[b]indole Scaffold by Annulative Two-Carbon Ring-Expansion.

Tymann Dina Christina DC Benedix Lars L Iovkova Lyuba L Pallach Roman R Henke Sebastian S Tymann David D Hiersemann Martin M

Chemistry (Weinheim an der Bergstrasse, Germany) 20200817 52

We report on the implementation of the concept of a photochemically elicited two-carbon homologation of a π-donor-π-acceptor substituted chromophore by triple-bond insertion. Implementing a phenyl connector between the slide-in module and the chromophore enabled the synthesis of cylohepta[b]indole-type building blocks by a metal-free annulative one-pot two-carbon ring expansion of the five-membered chromophore. Post-irradiative structural elaboration provided founding members of the indolo[2,3-d ...[more]

PMID: 32463529

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