BF ₂ Complexes of N ‐arylated 1‐amino‐anthraquinone, ‐xanthone, ‐thioxanthone, and Related Compounds: Synthesis and Properties

The physical properties of anthraquinones can be modulated by the introduction of arylamino groups next to the carbonyl function. Indeed, formation of an intramolecular hydrogen bond can enhance atom polarization and thus reduce their highest occupied molecular orbital‐lowest unoccupied molecular orbital energy gap, resulting in light absorption at longer wavelength. In this study, it successfully prepares different arylamino derivatives of anthraquinone, xanthone, and thioxanthone, compounds that are readily converted to their respective boracycles by reaction with BF 3 ·Et 2 O. The effect of the BF 2 moiety on the electronic properties is evaluated by electrochemical and photophysical studies. These studies respectively reveal for the complexes easier reduction and red‐shifted absorption wavelengths. In addition, promising 8% fluorescence quantum yield and 52% singlet oxygen quantum yield are recorded for one of the diboron‐anthraquinone complexes. Representative compounds are finally tested on a panel of disease‐related protein kinases.