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Photoinduced transition-metal- and external-photosensitizer-free intramolecular aryl rearrangement via C(Ar)-O bond cleavage.

ABSTRACT: The use of photochemical reactions that do not require expensive photocatalysts or transition metals is an environmentally friendly strategy for accomplishing a variety of structural transformations. Herein, we report a protocol for photoinduced transition-metal- and external-photocatalyst-free intramolecular heteroaryl/aryl rearrangement reactions of 2-heteroaryl/aryloxybenzaldehydes. The protocol was compatible with a variety of functionalities, including methyl, methoxy, cyano, ester, trifluoromethyl, halogen, and heteroaromatic rings. Control experiments suggested that the reaction proceeded via a photoinduced intramolecular heteroaryl/aryl rearrangement process involving photoexcitation of the aldehyde carbonyl group, radical addition, C-C bond formation and C(Ar)-O bond cleavage.

SUBMITTER: Dou Q

PROVIDER: S-EPMC7425081 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Photoinduced transition-metal- and external-photosensitizer-free intramolecular aryl rearrangement <i>via</i> C(Ar)-O bond cleavage.

Dou Qian Q Li Chao-Jun CJ Zeng Huiying H

Chemical science 20200526 22

The use of photochemical reactions that do not require expensive photocatalysts or transition metals is an environmentally friendly strategy for accomplishing a variety of structural transformations. Herein, we report a protocol for photoinduced transition-metal- and external-photocatalyst-free intramolecular heteroaryl/aryl rearrangement reactions of 2-heteroaryl/aryloxybenzaldehydes. The protocol was compatible with a variety of functionalities, including methyl, methoxy, cyano, ester, trifluo ...[more]

PMID: 32864086

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