Fluorescent Properties of 8-Substituted BODIPY Dyes: Influence of Solvent Effects

Abstract

Three boron-dipyrrine (BODIPY) based dyes with bulky substituents in 8-position of dipyrrin ligand have been synthesized and characterized. Photophysical properties of the obtained compounds have been investigated in different individual solvents and solvent mixtures. Investigated compounds was found to be intensive fluorescent molecular rotors. The influence of different solvent parameters and the substituent nature on rotor characteristics have been observed and discussed. Minor changes in the nature of 8-substituent does not influence the spectral properties, but the presence of nitrogen donor atom in the phenyl substituent could be used for the sensing of the donor-acceptor interactions with solvent or dissolved compounds. The new approach of spectral properties correlation with solvent parameters was proposed, the viscosity parameter should be taken into account in case of BODIPYs with bulky substituents. The intensity of fluorescence molecular rotor properties decrease gradually with the viscosity increase above 1 cP.

One-Pot Synthesis of Rotationally Restricted, Conjugatable, BODIPY Derivatives from Phthalides

“…In these derivatives, the presence of an ortho-functionalized aryl group attached at the meso position of the BODIPY-core hardly modifies the photophysics of the parent dyes (Table and Figure S1, where the absorption and fluorescence spectra for the representative derivatives 3 , 15a , and 17a bearing ortho-hydroxymethyl groups are depicted). In fact, the photophysical properties of the new derivatives seem independent of the nature of the substituent (i.e., hydroxyl or azide), as well as of the physicochemical properties of the media, in view of previously reported results for related 8-phenylBODIPYs . Just a slight increase in the absorption coefficient and a slight bathochromic shift of the spectral band is promoted in all cases.…”

Heavy-Atom Free spiro Organoboron Complexes As Triplet Excited States Photosensitizers for Singlet Oxygen Activation

“…The syntheses of BODIPY dyads were performed according to the known or modified literature protocols. − The borafluorene-based BODIPYs Bf-A1, Bf-A2, and Bf-A3 were obtained from the corresponding dipyrromethene ligand precursors (A1-H, A2-H, A3-H) and 9-chloroborafluorene in the presence of base ( i -Pr) 2 NEt. The remaining considered borafluorene complexes were synthesized in a similar way following a procedure reported by us …”

“…Synthesis. (Z)-3-Ethyl-5-[(4-ethyl-3,5-dimethyl-2H-pyrrol-2ylidene)phenylmethyl]-2,4-dimethyl-1H-pyrrole, A1-H. 42 Benzaldehyde (1.5 mL, 15 mmol) was added to a solution of 3-ethyl-2,4dimethylpyrrole (4 mL, 30 mmol) in DCM (100 mL) at room temperature (r.t.). The solution turned deep yellow.…”

Selective population of triplet excited states in heavy-atom-free BODIPY-C60 based molecular assemblies

“…The fullerene building block shows typical absorption spectrum of methanofullerene with an intense band at 330 nm and a small sharp band at 428 nm [34]. The main absorption band of the BDP located at 527 nm corresponds to the S 0 -S 1 transition in phenyl-substituted BDPs [35,36] whereas a weaker and broader feature at 380 nm corresponds to the S 0 -S 2 transition [36] (Fig. SI-4).…”