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Liquid chromatography–mass spectrometry has been used to analyse a range of cationic aniline dyes from the 19th century. Mauveine from the Chandler museum is used as a standard for comparison. This consists of a typical W. H. Perkin mixture of mauveine A and B. Mauveine from a historic collection in Dresden is different and consists of mainly mauveine A and a monomethyl mauveine chromophore. Possible synthetic routes and its significance are discussed. Three samples of phenylated rosanilines have been analysed, and a list of 19 possible components compiled. An analysis by liquid chromatography–mass spectrometry works well on this complex mixture giving clear information on retention times and accurate mass molecular weights. Mono-, di- and triphenylrosanilines are present in two samples, and a third sample has mainly monophenylrosaniline. In each sample, a small amount of higher molecular weight homologues appear. The thin-layer chromatography plate, from left to right, has fuchsin or rosaniline then mono-, di- and triphenylrosaniline. The two spots on the right-hand side are blue, and the two spots on the left-hand side are red.

Mauveine chromophores and a family of phenosafranins have been extracted from the Colour Experience Museum black precipitate with boiling ethanol and separated by chromatography. Phenosafranin (287.1295), monomethylphenylsafranin (301.1452) and a dimethylphenosafranin (315.1609) were observed. Tentative evidence for small quantities of N- tert-butylmauveine A and N- tert-butylmauveine B has been found by comparison of the data to standard retention times and accurate mass data. A synthetic method which reproduces the composition of mauveine extracted from the black precipitate, which is rich in mauveine A, is described.

Our proposal that museum-stored mauveine was made by a modified method compared to mauveine made by the William Henry Perkin patented method of 1856 is exemplified. An improved method of purification allows greater resolution and separation of the different mauveine chromophores. Liquid chromatography-mass spectrometry charts for museum-stored mauveine are compared to the new mauveine reported here. The formation of deprotected mauveine chromophores and N-tert- butylated mauveine chromophores is discussed.

Mauveine samples stored in museums in Sudbury, Bradford and Manchester are similar and are shown to be rich in mauveine A and mauveine B by liquid chromatography-mass spectrometry. By varying the aromatic amine composition of W.H. Perkin's 1856 patented method of mauveine synthesis, it is shown that they were not made by this method as W.H. Perkin disclosed it. An explanation for this is described.

Natural dyes and pigments could be obtained from insects, plants, and animals. Natural dyes have been utilized in the dyeing of wool, cotton, and silk since the prehistoric ages. The first applications of natural dyes on textile fibers are estimated to have started in Mesopotamia and India in 4000 BC. In these first dyeing trials, it is thought that pigments were used for dyeing process and these pigments could be easily removed from fabrics by friction and washing because of their weak mechanical bonding onto the fibers, and therefore, dyeing process was not really successful. It is thought that mordant dyeing method may have been accidentally discovered. In many countries, such as India, Egypt, Anatolia, and China, many historical natural dyed fabrics were found. One of the first synthetic dyes, mauveine (also known as aniline purple), was accidentally synthesized by W.H. Perkin (at the age of 18) in 1856 during attempts to make quinine. The discovery of the first synthetic dye changed the natural dyeing habits and synthetic dyes replaced almost all natural dyes. However, it is known that the wastewater produced in the production steps of synthetic dyes and the chemicals used in the textile dyeing process can have toxic and pollutant effects on human and environmental health. Nowadays, the effects of environmental awareness, organic products, and the tendency toward healthy lifestyle also reflect on the textile sector. Disagreements on the risks of the usage of synthetic dyestuffs and increasing environmental awareness result in an enhanced interest in natural resources, environmentally friendly products, and new strategies. That is one of the reasons why the use of natural dyes came back to the agenda due to an increased ecological and sustainable awareness. Unlike non-renewable raw materials of synthetic dyes, natural dyes are mostly renewable and sustainable. Natural dye sources are agriculturally renewable sustainable vegetable-plant-based colorant sources. In terms of sustainability, synthetic dyes are produced from non-renewable resources; however, natural dyes are extracted from renewable sources. The ability to obtain the dye from renewable natural sources makes natural dyes an attractive dye class for more sustainable world. Natural dyes can be applied on the fibers not only with dyeing method but also with printing method. Textile printing is one of the most important and versatile methods among the methods used to design and colorize textile fabrics. Ancient men and women mixed the colorants such as coal or soil paint with oils and used them with their fingers in lines on various materials. The staining of the plant extracts and fabrics has provided different approaches. The patterns can be produced by the wax applications to provide resistant dye liquor, or the surrounding areas provide a tightly attached and reserved area. The word of print is referred to a process that uses pressure to impart colorant to the material. And there is no doubt that the first textile printing was occurred by the blocks with embossed printing surfaces, then these blocks were inked and printed on the fabric. Some of the first blocks were made of clay or terracotta, while others were made of carved wood. In this chapter, the information about various eco-friendly prints and different printing techniques which were applied to different kinds of fibers and fabrics using sustainable natural dyes and natural pigments are given in detail.

The oxidation of aniline or a mixture of aniline with o-toluidine and p-toluidine following Runge's original method as carefully as possible, using chloride of lime [Ca(OCl)2], produces a coloured solution from which small amounts of mauveine were purified, isolated and analysed by LC-MS. The oxidation of aniline by the method of Fritsche and Beissenhirtz, using potassium dichromate and sulfuric acid, similar to W.H. Perkin's patented method, also gave small quantities of mauveine. The composition of the anilines are suggested depending upon their sources and Kekulé's comments on these early contributions are summarised.

The very concept of dye and pigment chemistry that was long known to the industrial world underwent a radical revision after the discovery and commercialization of dyes such as mauveine, indigo, and so on. Apart from their conventional role as coloring agents, organic dyes, and pigments have been identified as indispensable sources for high-end technological applications including optical and electronic devices. Simultaneous with the advancement in the supramolecular chemistry of π-conjugated systems and the divergent evolution of organic semiconductor materials, several dyes, and pigments have emerged as potential candidates for contemporary optoelectronic devices. Of all the major pigments, diketopyrrolopyrrole (DPP) better known as the ‘Ferrari Pigment’ and its derivatives have emerged as a major class of organic functional dyes that find varied applications in fields such as industrial pigments, organic solar cells, organic field–effect transistors, and in bioimaging. Since its discovery in 1974 by Farnum and Mehta, DPP-derived dyes gained rapid attention because of its attractive color, synthetic feasibility, ease of functionalization, and tunable optical and electronic properties. The advancement in supramolecular polymerization of DPP-based small molecules and oligomers with directed morphological and electronic features have led to the development of high performing optoelectronic devices. In this review, we highlight the recent developments in the optoelectronic applications of DPP derivatives specifically engineered to form supramolecular polymers.

There is an increased research interest in the molecules of colour, notably, some that have had an impact in ancient times. These could be rechristened as the molecules of Art. A common denominator with these molecules of Art, from their presence in different works of Art, through use in the first postage stamps, through current applications in blue pen inks, redox flow batteries or solar cell devices, relies in their stability towards light induced degradation: photostability. Examples of current research on these molecules will be summarized in this chapter. The iconic mauveine dye, sparks this contribution, both because it is still the focus of current research works, and also because it is an example of a highly photostable molecule.

In this paper, the application of a multi-analytical approach for the characterisation of synthetic and natural dyes in a historical textile is presented. The work is focused on a historical dress of a Sicilian noblewoman, dating from about 1865–1870. Firstly, SERS on fibre was performed, in order to individuate the classes of dyes employed. The SERS spectra suggested the presence of two main dyes: mauveine and orcein. In order to confirm these preliminary results, two different extraction protocols were applied. The extracts obtained were analysed by ESI-MS, MALDI-ToF and UHPCL-MS analyses, confirming the SERS results. In particular, the application of the ammonia mild extraction technique allowed to selectively extract the phenoxazonic dyes, separating them already in the extraction step from the synthetic ones. Thanks to this multi-analytical approach, this dress could be considered as one of the first examples of employment of synthetic dyes in association with natural ones.

Safranine was one of the earliest coal tar dyes following mauveine. By the end of the 19th century, many alkylated derivatives of safranine had been made. The history, identity, names, manufacture, analysis, toxicity, textile dyeing, and biological staining applications, plus some nonstaining uses of safranine, phenosafranine, methylene violet, amethyst violet, azocarmine, and Magdala red are described here.

Pseudo-mauveine picrate and a synthetic derivative of mauveine, 3-phenylamino-5-(2-methylphenyl)-7-amino-8-methylphenazinium picrate, have been prepared via their leuco-bases and their crystal structures determined. Time-dependent density functional theory gives a good match for the calculated and measured UV-Vis spectra.

John Plater graduated with First Class Honours from Loughborough University and then completed a PhD mentored by Charles W. Rees at Imperial College in London, working on an interface of organic and inorganic chemistry in the heterocyclic sulfur nitrogen group. After one year of postdoctoral research, mentored by W. Clark Still at Columbia University in New York, working on pre-organised polyether podands, he took up his post as a lecturer at Aberdeen University. A failed attempt to make pseudo-mauveine from 10 g of aniline led the author into an on-going 6-year research programme. Drawing inspiration from the collective work of many others, recent results cast doubt on Perkin's stated method for making authentic mauveine. Uncovering an improved route into synthetic derivatives of mauveine, which contain a 3-[(N-alkyl)aryl] substituent, has led by chance to a removable and traceless 3-(N-alkyl) protecting group, which alters the composition of mauveine to closely match that of the museum-archived samples. The possibility that W. H. Perkin or others exploited this method to make mauveine is considered.

The compositions of modern mauveines I and II made using tert-butyl-p-toluidine are analysed by HPLC and compared with authentic mauveine and a standard consisting of mauveine A, B2, B and C. The composition of modern mauveine II is similar to that of authentic mauveine.

Indigo, alizarin, mauveine, brazilin and brazilein (the latter two being major colour constituents of Brazilwood) are molecules that have had a strong impact in our civilization. The colour and longevity of these molecules is linked to their photostability, which have different origins. In this contribution the photochemistry and photophysics of these and other molecules will be reviewed, and linked with relevant issues such as the photostability, photoisomerization, mechanisms of photodegradation, the origin of the colour, and the incorporation in different matrices. In some cases, stability is associated with excited state proton transfer, while in the case of indigo it also forms Maya Blue, the pigment of the ancient Central American civilizations, with the clay palygorskite.

Mauveine, an iconic dye, first synthesised in 1856 still has secrets to unveil. If nowadays one wanted to prepare the original Perkin’s mauveine, what would be the procedure? It will be described in this work and lies on the use of a 1:2:1 (mole) ratio of aniline, p-toluidine and o-toluidine. This was found from a comparison of a series of products synthesized from different proportions of these starting materials, with a set of historical samples of mauveine and further analysed with two unsupervised chemometrics methods.

1-(Phenylamino)pseudo-mauveine was prepared by the oxidation of 1,3,5-tris(phenylamino)benzene and p-phenylenediamine with potassium dichromate. The absorption maximum of 535 nm is shifted hypsochr...

This work was supported by the Ministerio de Ciencia e Innovacion de Espana (project FIS2010-15405).

The oxidation of a mixture of N-tert-butyl- p-toluidine/aniline/ o-toluidine (1: 1.5: 1.5) with K2Cr2O7 in H+/H2O followed by de- tert-butylation with acid gives mauveine A and mauveine B. These compounds dye silk the same shade of red mauve as that of silk dyed by authentic mauveine.

Oxidation of phenosafranin and an excess of aniline gave a novel hydroxylated derivative of pseudo-mauveine. N-Methyl- p-toluidine and bis(4-methylphenyl)amine are efficient building blocks for making mauveine-related chromophores. Their oxidation with K2Cr2O7 is believed to form nitrogen centred radicals which then couple with an aromatic amine by homolytic aromatic substitution of hydrogen. The N-methyl substituent and the p-methyl sub-stituents are essential for the reaction to proceed. N-Methyl substituted chromophores were not demethylated in the reaction or by oxidation with K2Cr2O7 in dilute H2SO4. N-Nitroso-bis(4-methylphenyl)amine rearranges smoothly to the orange compound, (2-nitro-4-methylphenyl)-4-methylphenylamine, when a solution in CH2Cl2 is treated with montmorillonite at room temperature for 24 h. 2,4-Dimethylaniline has been used to make a mauveine homologue. The colour of silk dyed with mauveine chromophores has been compared to the colour of silk dyed with authentic 1862 mauveine.

Treatment of N-phenyl- p-phenylenediamine and two equivalents of aniline with potassium dichromate in hot water acidified with a small amount of sulfuric acid gives 3-phenylamino-5-phenyl-7-aminophenazinium sulfate (pseudo-mauveine). The oxidation of N-phenyl- p-phenylenediamine and o-toluidine with potassium dichromate in water with a small amount of sulfuric acid gives 3-phenylamino-5-( o- toluyl)-7-amino-8-methylphenazinium sulfate. Oxidation of aniline and ( o or p) toluidine only gave small quantities of mauveine chromophores. Oxidation of p-toluidine gives a known dimer which gives a purple coloured solution in acid. A hypothesis is described in which N-phenyl- p-phenylenediamine may have been involved in mauveine synthesis in the nineteenth century.

Today we cannot imagine our lives without a variety of colours. Every colour we see, consume, enjoy, apply and use wherever we need has a dye associated with it. More than 90% of the thousands of dyes used now are synthetic. A little more than 150 years ago a handful of dyes of only natural origin were available. In 1856 the era of synthetic dyes was ushered in by a spirited young chemist, William Henry Perkin, when he was trying to synthesize quinine, but obtained a coloured substance instead. It was a much desired colour and therefore became an instant hit. The following is an account of Perkin’s life as a chemist and an industrialist par excellence.

Those of us who owe our living in part to the global dyestuff and chemical industry should pause today and remember the beginnings of this giant industry which started 150 years ago today with William Perkins’ discovery of mauveine whilst working in his home laboratory during the Easter holiday on April 28, 1856. Prior to this discovery, all textiles were dyed with natural dyestuffs and pigments.

The equilibrium structure of the mauveines has been studied with the density functional theory. The molecular framework consists of a planar diaminophenazine with a centrally appended perpendicular phenyl ring and a laterally bound twisted aminophenyl group. Of the three aromatic fragments, it is only the aminophenyl part that exhibits a conformational flexibility around the C(phenazine)–N–C(phenyl) bonds. The electronic absorption spectra have been examined using hybrid time-dependent density functional theory. The π → π ∗ excitations, mainly occurring in the phenazine moiety, are the major contributors to the strong absorption bands. Intramolecular π-charge transfer from the appended phenyl rings to the phenazine nucleus give rise to weakly-allowed transitions.

Color is one of the elements of nature that makes the human life more aesthetic and fascinating in the world. Plants, animals, and minerals have been used as primary sources for colorants, dyes or pigments since ancient times. The first fiber dyes known to be used in prehistoric times consisted of fugitive stains from berries, blossoms, barks, and roots. This chapter is devoted to an historical introduction to the colorants, taking into account of the chronological developments in dyeing processes and the origins of dyes used. Even today, the dyeing using natural materials is applied as an adjunct for hand spinning knitting and weaving but it has remained as a living craft in many traditional cultures of North America, Africa, Asia, and the Scottish Highlands. The new discoveries about the science of color have also led to many industrial innovations and a sharp fashion change. Scale insects have long been used to produce crimson-colored dyes. Many plant pigments are used as dyes. Madder has been utilized since times as a red vegetable dye for leather, wool, cotton and silk. Indigo is a natural dye that is structurally related to betalains. Tyrian purple, which is an ancient dye, has been extracted from shellfish of the Murex genus.

Why do certain ancient natural dyes, such as indigo, preserve their colour so well while others, like brazilein, seem to degrade much faster? And how did mauveine change the world of colour? Will modern binding media, as vinyl paints, perform as well as a medieval tempera? Will it be possible to predict their durability? Photochemistry can answer many important questions about materials’ stability, providing new tools for the conservation of treasured artworks.

Acknowledgements Authentic mauveine and Schunk’s mauveine were kindly provided from the Beaufoy-Kirkpatrick Collection, Museum of Science and Industry, Manchester. The National Mass Spectrometry Service Centre provided mass spectra.

7 pags.; 6 figs.; 2 tabs., © 2015 American Chemical Society. Mauve was the first synthetic organic dyestuff to be manufactured industrially. The main components of the dye are mauveine A, B, B2, and C. These molecules show four nitrogen atoms in their structure. Therefore, they can interact with the SERS substrate by four different sites. In this study the Raman and SERS spectra of the mauve and its components were obtained in order to determine the adsorption mechanism on Ag nanoparticles. The comparison of the Raman and SERS spectra of mauve dye revealed several differences in the intensity and position of the Raman bands. Thus, a chemical interaction between the dye and the Ag nanoparticles was concluded. DFT calculations of the four mauveine molecules were carried out to aid in the assignments of the vibrational normal modes., We are indebted to the National Institute of Justice (Department of Justice Award #2006-DN-BX-K034) and the City University Collaborative Incentive program (#80209). This work was further supported by the National Science Foundation grant number CHE-1402750 and by the City University of New York PSC-BHE Faculty Research Award Program. This work was also supported by Ministerio de Ciencia e Innovacion de España (project FIS2010-15405).

One hundred and fifty years ago the world of coloration changed forever with William Henry Perkin's discovery of the first synthetic dye derived from coal tar. The life, work and legacy of Sir William Henry Perkin are reviewed in the light of his early chemical education, his training in coal tar chemistry with Hofmann, and his discovery, patenting and manufacture of mauveine. This was the first synthetic dyestuff to be manufactured in a purpose-built industrial chemical plant anywhere in the world.