One blue laser merocyanine dye, named 5-[(1-methylpyrrol-2-yl)methylene]-rhodanine, was synthesized by using N-methyl-pyrrolylcarbonyl and rhodanine as starting materials and piperidine as catalyst. The product was identified by ¹H NMR, IR, UV-vis spectra and elemental analysis. The crystal structure of the dye was determined by X-ray single crystal diffraction analysis. The UV-vis and fluorescence spectra of rhodanine blue laser merocyanine dye in different solvents were investigated. The experimental results show that the crystal belongs to monoclinic system with space group C2/c, a＝1.6736(3) nm, b＝0.74588(11) nm, c＝1.6567(3) nm, F(000)＝928, Z＝8, V＝2.0637(6) nm³, D_c＝1.444 g/cm³, μ＝0.482 mm^－1. Intermolecular associations occur by π…π stacking, N—H…O hydrogen bonds and weak S…S interaction, which contribute to stabilize the crystal structure. The absorption maximum and molar extinction coefficient of the dye in common solvents (CHCl₃, DMSO, H₂O, CH₃COCH₃, EtOH and MeOH) were situated at 428.0～443.5 nm and 1.8×10⁴～2.1×10⁴ dm³•mol^－1•cm^－1 respectively, which indicated that the dye exhibited intensive absorption in blue light region.

Key words: blue laser merocyanine dye, rhodanine, N-methyl-2-pyrrolylcarbonyl, spectral property, crystal structure