A series of unsymmetric pentamethine cyanine dyes featuring benzoxazolyl and benzothiazolyl groups were synthesized, the structures were characterized by 1H NMR, UV– vis absorption spectroscopy and mass spectrometry. The dyes with different anions such as chloride, tetraphenylborate and tetra (4-fluorophenyl) borate were also obtained and their solubility can be changed by the choice of the anion part. The third-order nonlinear optical ...
