The importance of quinonoidal planarity in improving the wet fastness of acid dyes was studied in a new series of N‐sulphonatoalkyl‐substituted indophenine derivatives. These derivatives were synthesised via the sulphonatoalkylation reaction of isatins with alkanesultone or sodium bromoalkanesulphonate followed by the indophenine reaction. The effects of the position of sulphonic acid groups, length of the alkyl chain, and electron‐donating/withdrawing groups on geometry, electronic structure, solubility, and absorption properties were systematically examined and correlated with the performances of the dyes on wool, silk and nylon fabrics. The N‐sulphonatoalkyl indophenine dyes could exhibit a blue colour in N,N‐dimethylformamide (DMF) and on silk or nylon fabric but a purplish colour in water and on wool fabric. Methoxy groups had a negative impact on the molar extinction coefficient and dye exhaustion, leading to relatively poor dyeing performance. In comparison, fluorine or chlorine atoms were less influential. The introduction of nitro groups could induce a yellowness to the dyed fabrics caused by the strengthened absorption at the region of 360 to 420 nm and reduce the dyeing rate and wet fastness level due to the low dye–fibre affinity. In general, the N‐sulphonatoalkyl indophenine dyes exhibited satisfactory washing and rubbing fastness, especially on dyed nylon fabric. This study provides insight into the structure–property relationship of indophenine dyes and demonstrates that sulphonatoalkylation is an efficient methodology for designing high‐performance textile dyestuffs based on quinonoidal heterocyclic structures.

中文翻译：

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N-磺基磺基烷基吲哚芬衍生物：羊毛，丝绸和尼龙织物的设计，合成和染色性能

在一系列新的N-磺酰基烷基取代的吲哚芬宁衍生物中研究了醌型平面度对提高酸性染料的湿牢度的重要性。这些衍生物是通过靛红与链烷磺酸内酯或溴链烷磺酸钠的磺酰基烷基化反应，然后通过吲哚芬宁反应合成的。考察了磺酸基团的位置，烷基链的长度以及给电子/吸电子基团对几何形状，电子结构，溶解度和吸收性能的影响，并将其与染料在羊毛，丝绸和羊毛上的性能相关联。尼龙面料。N-磺基磺酸烷基吲哚芬染料在N，N中可能显示蓝色‐二甲基甲酰胺（DMF）以及在丝绸或尼龙织物上，但在水中和羊毛织物上呈紫色。甲氧基对摩尔消光系数和染料耗尽有负面影响，导致相对较差的染色性能。相比之下，氟或氯原子的影响较小。硝基的引入可能会由于在360至420 nm区域吸收增强而使染色的织物发黄，并且由于低的染料-纤维亲和力而降低了染色速度和湿坚牢度。通常，N磺基磺基烷基吲哚芬染料具有令人满意的耐洗牢度和耐摩擦性，特别是在染色的尼龙织物上。这项研究提供了对吲哚酚染料的结构-性质关系的深入了解，并证明了磺酰基烷基化是一种基于醌型杂环结构设计高性能纺织染料的有效方法。