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Arylazoindazole Photoswitches: Facile Synthesis and Functionalization via SNAr Substitution.

ABSTRACT: A straightforward synthetic route to arylazoindazoles via nucleophilic aromatic substitution is presented. Upon deprotonation of the NH group, a C6F5-substituted formazan undergoes facile cyclization as a result of intermolecular nucleophilic substitution (SNAr). This new class of azo photoswitches containing an indazole five-membered heterocycle shows photochemical isomerization with high fatigue resistance. In addition, the Z-isomers have long thermal half-lives in the dark of up to several days at room temperature. The fluorinated indazole group offers a handle for further functionalization and tuning of its properties, as it is shown to be susceptible to a subsequent, highly selective nucleophilic displacement reaction.

SUBMITTER: Travieso-Puente R

PROVIDER: S-EPMC5345119 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Arylazoindazole Photoswitches: Facile Synthesis and Functionalization via SNAr Substitution.

Travieso-Puente Raquel R Budzak Simon S Chen Juan J Stacko Peter P Jastrzebski Johann T B H JT Jacquemin Denis D Otten Edwin E

Journal of the American Chemical Society 20170224 9

A straightforward synthetic route to arylazoindazoles via nucleophilic aromatic substitution is presented. Upon deprotonation of the NH group, a C6F5-substituted formazan undergoes facile cyclization as a result of intermolecular nucleophilic substitution (SNAr). This new class of azo photoswitches containing an indazole five-membered heterocycle shows photochemical isomerization with high fatigue resistance. In addition, the Z-isomers have long thermal half-live ...[more]

PMID: 28218846

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