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Sequence-independent activation of photocycloadditions using two colours of light.

ABSTRACT: We exploit two reactive chromophores to establish sequence-independent photochemical activation, employing ortho-methyl benzaldehyde (oMBA) and N,N-(dimethylamino)pyrene aryl tetrazole (APAT) with N-(2-hydroxy)ethyl maleimide (NHEM), without any additives. Critically, the order of the irradiation sequence is irrelevant, as the shorter wavelength does not activate the higher wavelength activated species. Therefore, full sequence-independent λ-orthogonality is achieved through differences in both the reaction quantum yields (Φ _r,oMBA and Φ _r,APAT) and wavelength-dependent reactivity profiles of the employed chromophores.

SUBMITTER: Kamm PW

PROVIDER: S-EPMC8729803 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Sequence-independent activation of photocycloadditions using two colours of light.

Kamm Philipp W PW Rodrigues Leona L LL Walden Sarah L SL Blinco James P JP Unterreiner Andreas-Neil AN Barner-Kowollik Christopher C

Chemical science 20211214 2

We exploit two reactive chromophores to establish sequence-independent photochemical activation, employing ortho-methyl benzaldehyde (oMBA) and N,N-(dimethylamino)pyrene aryl tetrazole (APAT) with N-(2-hydroxy)ethyl maleimide (NHEM), without any additives. Critically, the order of the irradiation sequence is irrelevant, as the shorter wavelength does not activate the higher wavelength activated species. Therefore, full sequence-independent λ-orthogonalit ...[more]

PMID: 35126985

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