Studies on crystal structures, optical, solubility and dyeing properties of two new crystalline dye salts based on berberine with aromatic carboxylic acid

Abstract

• Two crystalline dye salts were assembled and characterized. • The noncovalent interactions in the salts have been analyzed. • Their optical characteristics and physical properties were also preliminary investigated. In this work, the two new crystalline dye salts [BB]·[PPA] ( 1 ) and [BB]·[SSA] ( 2 ) of Berberine (BB) with aromatic carboxylic acid were obtained. The structures of 1-2 were determined by the single crystal X-ray diffraction, in which the coplanarity of the aromatic rings may give more overlap between the host-guest units. Results showed that these two new crystalline dye salts did not only drastic change in optical characteristics but also significantly improve the dissolution rate, and the color strength (K/S) of the dyed fabrics.