Puchtler H, Meloan S N, Brewton B R
Histochemistry. 1975;41(3):185-94. doi: 10.1007/BF00497682.
The nature of products formed by aldehydes and Schiff's reagent, whether they are sulfonic or sulfinic acid compounds, has been the subject of much discussion. It seems therefore timely to review early studies of aldehyde-Schiff reactions, including the history of pararosanilin and related dyes. Dyes of the basic fuchsin group have been studied extensively since 1862, and their triphenylmethane structure was established in 1878. The currently used structural formulas were introduced around the turn of the century. Reactions of basic fuchsin with aldehydes, with and without addition of SO2, were investigated by Schiff in the 1860's i.e. before the structure of these dyes was known. In 1900 Prud'homme showed that the reaction products of basic fuschsin, sodium bisulfite and formaldehyde are alkylated and sulfonated derivatives of the parent compound; further chemical studies indicated attachment of the sulfonic acid group to the carbon atom of the aldehyde. Prud'homme's findings were repeatedly confirmed during the following decades. Wieland and Scheuing were apparently unaware of these studies and introduced the sulfinic acid theory in 1921; furthermore, they considered substitution at two amino group of Schiff's reagent essential for formation of the colored compound. However, later chemical and spectroscopic studies showed no evidence of-N-sulfinic acids but supported the sulfonic acid theory of Prud'homme.
醛与席夫试剂反应所形成的产物的性质，无论它们是磺酸还是亚磺酸化合物，一直是众多讨论的主题。因此，回顾醛 - 席夫反应的早期研究，包括副蔷薇苯胺及相关染料的历史，似乎是适时的。自1862年以来，碱性品红类染料就得到了广泛研究，其三苯甲烷结构于1878年得以确立。目前使用的结构式是在世纪之交前后引入的。19世纪60年代，即在这些染料的结构被知晓之前，席夫研究了碱性品红与醛的反应，有无添加SO₂的情况均有涉及。1900年，普鲁德'homme表明碱性品红、亚硫酸氢钠和甲醛的反应产物是母体化合物的烷基化和磺化衍生物；进一步的化学研究表明磺酸基团连接在醛的碳原子上。在随后的几十年里，普鲁德'homme的发现得到了反复证实。维兰德和朔伊宁显然不知道这些研究，并在1921年提出了亚磺酸理论；此外，他们认为席夫试剂的两个氨基发生取代对于有色化合物的形成至关重要。然而，后来的化学和光谱研究没有发现 -N- 亚磺酸的证据，而是支持了普鲁德'homme的磺酸理论。
