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Mauveine, also known as aniline purple and Perkin's mauve, was the first synthetic organic chemical dye, discovered serendipitously in 1856. ==Chemistry== Mauveine is a mixture of four related aromatic compounds differing in number and placement of methyl groups. Its organic synthesis involves dissolving aniline, ''p''-toluidine, and ''o''-toluidine in sulfuric acid and water in a roughly 1:1:2 ratio, then adding potassium dichromate.〔''A Microscale Synthesis of Mauve'' Scaccia, Rhonda L.; Coughlin, David; Ball, David W. J. Chem. Educ. 1998 75 769 (Abstract )〕 Mauveine A (C26H23N4+X−) incorporates 2 molecules of aniline, one of ''p''-toluidine, and one of ''o''-toluidine. Mauveine B (C27H25N4+X−) incorporates one molecule each of aniline, ''p''-toluidine, and ''o''-toluidine. In 1879, Perkin showed mauveine B related to safranines by oxidative/reductive loss of the ''p''-tolyl group. In fact, safranine is a 2,8-dimethyl phenazinium salt, whereas the parasafranine produced by Perkin is presumed〔Website source: ch.ic.ac.uk (Link )〕 to be the 1,8-(or 2,9) dimethyl isomer. The molecular structure of mauveine proved difficult to determine, finally being identified in 1994. In 2007, two more were isolated and identified: mauveine B2, an isomer of mauveine B with methyl on different aryl group, and mauveine C, which has one more ''p''-methyl group than mauveine A.〔J. Seixas de Melo, S. Takato, M. Sousa, M. J. Melo and A. J. Parola ''Revisiting Perkin's dye(s): The spectroscopy and photophysics of two new mauveine compounds (B2 and C)'' ''Chem. Commun.'' 2007; 2624–26 〕 Image:Mauveine a skeletal org.svg|skeletal formula of mauveine A Image:Mauveine b skeletal org.svg|skeletal formula of mauveine B Image:Mauveine b2 skeletal org.svg|skeletal formula of mauveine B2 Image:Mauveine c skeletal org.svg|skeletal formula of mauveine C In 2008, additional mauveines and pseudomauveines were discovered, bringing the total number of these compounds up to 12.〔''A Study in Mauve: Unveiling Perkin!s Dye in Historic Samples'', M. M. Sousa, M. J. Melo, A. J. Parola, P. J. T. Morris, H. S. Rzepa, and J. S. Seixas de Melo Chem. Eur. J., 2008, ''14'', 8507– 8513, 〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「mauveine」の詳細全文を読む スポンサード リンク
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