Syntheses, and Optical, Fluorescence, and Nonlinear Optical Characterization of Phosphine-Substituted Terthiophenes

Abstract

Earlier studies of phosphine-substituted terthiophenes have demonstrated that some of these materials exhibit nonlinear absorption at 532 nm. However, this wavelength is significantly removed from the linear absorption maxima of the complexes, suggesting that better nonlinear absorption might be observed at wavelengths closer to the linear absorption maxima. To investigate this possibility, a library of compounds has been prepared either by varying the group attached to the nonbonding pair of electrons on the phosphorus atoms of 5,5''-bis(diphenylphosphino)-2,2':5',2''-terthiophene (PT(3)P), or by introducing additional substituents on the 5''-position of 5-(diphenylphosphino)-2,2':5',2''-terthiophene (PT(3)). All these compounds have been characterized using multinuclear NMR, UV-vis, and fluorescence spectroscopy. The compounds are strongly fluorescent, and both the fluorescence wavelength and the intensity depend upon the thiophene substituents. The nonlinear optical properties have also been evaluated at various wavelengths in the blue region. Each compound exhibits reverse saturable absorption, and the intensity of the reverse saturable absorption at a particular wavelength depends on the chemical structure of the compound.

Synthesis, thermal analysis, and linear and nonlinear optical characterization of substituted polyphosphonates derived from 1,12-dodecanediol

“…Finally, UV/visible and fluorescence spectroscopies have been used to evaluate the linear optical properties of solutions of the 2,2′‐bithienyl‐5‐yl substituted polyphosphonates, and the nonlinear optical properties have been evaluated using nonlinear transmittance measurements at 430 nm with a 27 ps laser pulse. The results from these studies are compared with those from our previous studies of molecular phosphonate‐substituted thiophenes …”

Synthesis, Linear, and Nonlinear Optical Properties of Phosphonato‐Substituted Bithiophenes Derived from 2,2‐Dimethyl‐1,3‐propanediol

“…Finally, the packing of the pdP(X)T 2 H and pdP(X)T 2 P(X)pd (X = S, Se) molecules in the crystal lattice is of interest. In the previously studied bithiophenes substituted with diphenylphosphino or 2,2′‐biphenoxy‐derived phosphonato groups, a variety of both offset‐slipped and point to face π–π interactions were observed . These interactions occurred through both the oligothiophene π‐system and the aromatic phosphorus substituents, i.e.…”

“…We have previously reported the solid‐state structures of a number of bithiophenes with chalcogenophosphino or chalcogenophosphonato substituents . The degree of π–π stacking in these compounds was affected by the crystallization conditions, the X group and the phosphorus peripheral substituents.…”

“…We have recently reported that solutions of diphenylphosphino‐substituted oligothiophenes of the types Ph 2 P(X)T n H and Ph 2 P(X)T n P(X)Ph 2 (X = O, S, Se; T = 2,5‐C 4 H 2 S; n = 2, 3) exhibit NLA at wavelengths across the violet‐blue spectral region . The NLAs of Ph 2 P(X)T 3 H and Ph 2 P(X)T 3 P(X)Ph 2 were limited by the compounds' relatively high linear absorptions in the violet‐blue region.…”

Antiamoebic Activity of Adenophyllum aurantium (L.) Strother and Its Effect on the Actin Cytoskeleton of Entamoeba histolytica

“…Alpha-terthienyl is able to reduce the growth rate of Microsporum cookie , and it induces the presence of electron-dense vacuoles without causing damage to the cells ( Mares et al, 1990 ). Thiophenes could also be the cause of autofluorescent vacuoles in Aa EaR-treated amoebas because these compounds are strongly fluorescent ( Zhao et al, 2011 ).…”