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Two-colour light activated covalent bond formation.

ABSTRACT: We introduce a photochemical bond forming system, where two colours of light are required to trigger covalent bond formation. Specifically, we exploit a visible light cis/trans isomerization of chlorinated azobenzene, which can only undergo reaction with a photochemically generated ketene in its cis state. Detailed photophysical mapping of the reaction efficiencies at a wide range of monochromatic wavelengths revealed the optimum irradiation conditions. Subsequent small molecule and polymer ligation experiments illustrated that only the application of both colours of light affords the reaction product. We further extend the functionality to a photo reversible ketene moiety and translate the concept into material science. The presented reaction system holds promise to be employed as a two-colour resist.

SUBMITTER: Walden SL

PROVIDER: S-EPMC9135712 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Two-colour light activated covalent bond formation.

Walden Sarah L SL Rodrigues Leona L LL Alves Jessica J Blinco James P JP Truong Vinh X VX Barner-Kowollik Christopher C

Nature communications 20220526 1

We introduce a photochemical bond forming system, where two colours of light are required to trigger covalent bond formation. Specifically, we exploit a visible light cis/trans isomerization of chlorinated azobenzene, which can only undergo reaction with a photochemically generated ketene in its cis state. Detailed photophysical mapping of the reaction efficiencies at a wide range of monochromatic wavelengths revealed the optimum irradiation conditions. Subsequent small molecule and polymer liga ...[more]

PMID: 35618722

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