Syntheses and UV–visible spectroscopic properties of new ‘fluorophilic’ fluorine‐ and perfluoroalkyl‐substituted solvatochromic pyridinium N‐phenolate betaine dyes

Abstract

Syntheses and negative solvatochromism of three new ‘fluorophilic’ fluorine‐ and perfluoroalkyl‐substituted pyridinium N‐phenolate betaine dyes 3–5 are described in order to obtain new zwitterionic dyes which should be less basic and better soluble in perfluorinated solvents than the solvatochromic standard betaine dyes 1 and 2, used to establish an empirical scale of solvent polarity, called the E T (30) or $E_{T}^{N}$ scale. The new betaine dyes 3–5 were designed to allow an extension of the existing E T (30) scale to new solvents. Copyright © 2001 John Wiley & Sons, Ltd.

Two‐Photon Solvatochromism II: Experimental and Theoretical Study of Solvent Effects on the Two‐Photon Absorption Spectrum of Reichardt’s Dye

“…Table 1). [128] As expected, the CT band is significantly blueshifted upon increasing solvent polarity (l max % 634-700 nm; cf. Depending on the solvent, the first band has a maximum value at l max % 304-309 nm (maximum extinction coefficient, e max % 36 860-46 000 L mol À1 cm À1 ) and the second band maximum lies in the range l max % 374-389 nm (e max % 9865-11 760 L mol À1 cm À1 ).…”

“…According to the orbital picture, this absorption band appears as an effect of intramolecular CT from the HOMO (localized mainly on the phenolate) to the LUMO (localized mainly on the pyridinium moiety). [128] As expected, the CT band is significantly blueshifted upon increasing solvent polarity (l max % 634-700 nm; cf. Table 1 and Figure 1); both the maximum of the molar extinction coefficient (e max ) and the oscillator strengths (f osc ) decrease with increasing solvent polarity.…”

Measuring the Micro-Polarity and Hydrogen-Bond Donor/Acceptor Ability of Thermoresponsive N-Isopropylacrylamide/N-tert-Butylacrylamide Copolymer Films Using Solvatochromic Indicators

“…The hydrogen-bond accepting ability (β parameter) was found to be relatively independent of the film composition whereas the E T (30) (30) values for solvents were taken from Refs. [18,35,43].…”

Syntheses and UV–visible spectroscopic properties of two new hydrophilic 2,6‐di(carbamoyl)‐substituted solvatochromic pyridinium N‐phenolate betaine dyes

“…IR spectra: IFS 88 spectrophotometer (Bruker) with KBr discs. 1 H and 13 C NMR: ARX 200 and AC-300 spectrometers (Bruker) in CDCl 3 and CD 3 SOCD 3 with tetramethylsilane as internal standard. Mass spectra: MAT CH-7A spectrometer (Varian) with electron ionization (EI, 70 eV) and MAT 711 (Varian) with field desorption (FD).…”