Single crystal X-ray structure determination and enantiomeric recognition of chiral dinuclear europium (III) complexes towards BINOL

Herein, we reported a pair of di-nuclear europium enantiomers [Eu 2 (PO 4 ) 6 (R-/S-HL) 6 (MeOH) 4 ]•2MeOH (R-complex( 1a ) and S-complex( 1b )) constructed from chiral ligands (R)-/(S)-(+)-1,1′-binaphthyl-2,2′-diyl hydrogenphosphate (R-/S-HL) and europium (III) nitrate by solvothermal method. The structure of the complexes was characterized by single-crystal X-ray diffraction, powder X-ray diffraction and Fourier transform infrared spectroscopy. It was found that R-complex( 1a ) and S-complex( 1b ) were chiral enantiomers with a zero-dimensional chiral cluster structure. The circular dichroism studies further revealed the chiral properties of R-complex( 1a ) and S-complex( 1b ). Moreover, fluorescence sensing tests demonstrated that R-complex( 1a ) and S-complex( 1b ) possessed high enantioselectivity for axially chiral BINOL racemates.