Activation of Anthraquinone's Electrophilicity by Light for a Dynamic C-O Bond.

Coupling of photoswitching with dynamic covalent chemistry enables control of the formation and cleavage of covalent bonds by light irradiation. -Aryloxyanthraquinones feature an exclusive ability to switch electrophilicity by interconversion between - and -quinone isomers, which was used for the first time for the implementation of a dynamic C-O bond. Photogenerated -isomers undergo a concerted -Michael addition of phenols to give hitherto unknown 4-hydroxy-10,10-diaryloxyanthracen-9-ones.

Revisiting Peri-Aryloxyquinones: From a Forgotten Photochromic System to a Promising Tool for Emerging Applications.

Emerging applications of photochromic compounds demand new molecular designs that can be inspired by some long-known yet currently forgotten classes of photoswitches. In the present review, we remind the community about Peri-AryloxyQuinones (PAQs) and their unique photoswitching behavior originally discovered more than 50 years ago. At the heart of this phenomenon is the light-induced migration of an aromatic moiety (arylotropy) in peri-aryloxy-substituted quinones resulting in ana-quinones.

1-Hydroxyanthraquinones Containing Aryl Substituents as Potent and Selective Anticancer Agents.

A series of 1,2-, 1,4-disubstituted or 1,2,4-trisubstituted anthraquinone-based compounds was designed, synthesized, characterized and biologically evaluated for anticancer efficacy. 2- or 4-arylated 1-hydroxy-9,10-antraquinones (anthracene-9,10-diones) were prepared by Suzuki-Miyaura cross-coupling reaction of 1-hydroxy-2-bromoanthraquinone, 1-hydroxy-4-iodoanthraquinone or 1-hydroxy-2,4-dibromoanthraquinone with arylboronic acids. The cross-coupling reaction of 2,4-dibromo-9,10-anthraquinone with arylboronic acids provide a convenient approach to 2,4-bis arylated 1-hydroxyanthraquinones with a variety of aryl substituent in the 2 and 4 position.