Anilines solvatochromic probes

This chapter examines various derivatives of aniline that have been used as solvatochromic probes of the abilities of solvents and other environments to solvate solutes. It is difficult to delimit what are aniline derivatives proper (aminonaphthalenes are not included, for instance) and not all the derivatives can be discussed in a chapter such as this. Nevertheless, certain dyes that have been extensively used as solvatochromic probes and that have... 

SCHEME 1. The structures of some of the substituted anilines used as solvatochromic probes... 

The ability of aniline derivative solvatochromic probes (5, 9, 27, 31, 36, 61, 66, 67 and 80) to characterize also the HBD abilities of solvents was reviewed by Novaki and El-Seoud100 on the basis of data from the literature. They determined the sensitivity coefficients of these probes to the ji and a solvent parameters. 

Bosch, Roses and coworkers explored the use of solvatochromic probes in solvent mixtures involving various alcohols with water as well as with other alcohols, hexane and benzene in a series of papers106-110. The aniline derivatives they employed were 5 for the polarity/polarizability and the 8/5 probe pair for the EPD/HBA properties of the mixtures, in conjunction with other suitable non-aniline probes. In order to ensure that what is being... 

Solvatochromic probes based on aniline derivatives have been used in a host of environments other than liquid solvents and their mixtures, supercritical fluids and room-temperature liquid salts. All these uses cannot be reviewed here and only examples of them are provided. 

Aniline derivatives have also been employed as solvatochromic probes to characterize the solvation abilities of various polymers and polymer surfaces. Thin films of various polymers were prepared by Paley and coworkers171 that incorporated the probe 7 for studying the polarity/polarizability and the probe pair 8/7 for studying the HBA/EPD... 

The two parts of the present volume consist of 17 chapters written by experts from 10 countries. They start with historical background, followed by chapters on the theory, structure, thermochemistry, photophysics and photochemistry and electrochemistry of anilines, on their mass spectrometry, NMR spectra and analysis and on their modern syntheses by transition metal catalysed processes. Other chapters deal with their rearrangements, their reactivity as nucleophiles, their use as solvatochromic probes, their hydrogen bonded complexes, and their versatile uses in the chemical industry, and the relevant topic of toxicity and environmental aspects. A chapter on a special group of anilines—the proton sponges—ends the book. 

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