Facile preparation and fluorescence properties of a soluble oligopyrrole derivative

• An oligopyrrole derivative (OMDPP) with unique structure was prepared.
• OMDPP had an average polymerization degree of 3 with a low polydispersity of 1.09.
• The formation mechanism of OMDPP was discussed.
• The fluorescence properties of OMDPP solution were investigated.

A soluble oligopyrrole derivative (OMDPP) was prepared based on a bipyrrole monomer 2-methyl-1,3-di(1H-pyrrol-1-yl) propan-1-one (MDPP) using chemical oxidation method. The characterization of the chemical structure indicated that OMDPP was mainly generated from the coupling of the pyrrole ring attached to the methylene group in the monomer. Our results also proved that OMDPP exhibited good solubility and film-forming ability. The fluorescence properties of OMDPP solutions were then characterized, and green emissions were observed in the wavelength range of 550–564 nm in a variety of solvents under the excitation wavelength of 467 nm. The research of solvatochromic behavior of OMDPP revealed that the electron donating-accepting property of the solvent possibly have greater impact on the Stokes shift of OMDPP solution compared with the polarity of the solvent. Additionally, the concentration (from 5*E-6 g/ml to 8*E-4 g/ml) and the excitation wavelength (287–507 nm) also exhibited obvious influences on the emission spectra of the OMDPP solution, which were investigated in detail.