Spectrophotometric Characteristics of New Pyridylindolizine Derivatives Solutions

Abstract

Three new pyridylindolizine derivatives, 1, 2, 3-tricarbometoxi-7-(4-pyridyl)-pyrrolo[1, 2-a]pyridine (I), 1,2-dicarboethoxy-3-(4-bromobenzoyl)-7-(4-pyridyl)-pyrrolo[1,2-a]pyridine (II) and its isomer 1,2-dicarboethoxy-3- (4-bromobenzoyl) -5- (2-pyridyl) -pyrrolo[1, 2-a]pyridine (III) have been investigated in different solutions by UV-VIS absorption, steady-state, and time-resolved fluorescence methods. The effects of the substituent and solvent on the spectroscopic properties have been demonstrated. The fluorescence decay data could be fitted to a single-exponential function. The lifetime values are higher in protic polar than in aprotic apolar solvents for compound I. In the case of compounds II and III the fluorescence intensities and lifetimes are very low, with the exception of III in aprotic solvents. The absorption and fluorescence properties of the compounds showed a solvent dependence.

Effect of substituents on the absorption properties of three pyridylindolizine derivatives: A DFT and TDDFT study

“…Moreover, spectral properties of indolizines can be modified by changing the nature and positions of the substituents and the solvent characteristics. Although several applications rely on the optical properties of indolizines, only in a few studies the relationship between the optical properties and the nature and positions of the substituents have been investigated [5][6][7][8].…”

New fluorescent indolizines and bisindolizinylethylenes

“…3 No significant difference was observed between the two main absorption bands of compounds 5a and 6a. Compounds 8a,b show a bathochromic shift as compared to the latter, 8a showing the highest absorbance of the series.…”

“…Compared to 4-pyridyl-7-indolizines, 3 the fluorescence spectra in solution of 6 and 8 show similar emission wavelengths and intensities, in spite of the presence of the ethylene spacer. However, when comparing 2-pyridyl-5-indolizines 3 to 5, a bathochromic shift is noted for the latter, due to the decreased steric strain caused by the ethylene bridge.…”

“…Pyrroloazines are an important class of N-bridgehead heterocycles due to their interesting biological 1,2 and optical properties, 3,4 as demonstrated by the large volume of literature available on the subject. [5][6][7][8][9][10] One of the most recent developments is the use of such compounds in optoelectronic devices, mostly as pure-color luminophores in OLEDs (organic light emitting diodes).…”

Helical chirality of pyrrolo[1,2-a][4,5]diazafluoren-5-one derivatives

“…[31][32][33][34][35][36][37][38][39] In order to explain the effects of the molecular structure and solvent-solute interactions on absorption spectroscopic properties, the compounds were investigated in different solvents. Representative solvents have been selected for this investigation.…”