Indigo structure

Likewise, P.B.63 is an aluminum lake. It is derived from the indigo structure, which is sulfonated to afford indigo-5,5 -disulfonic acid. For indigo syntheses, please see [1]. 

This is a pigment based on a thiazine indigo structure, of which no detailed composition has been disclosed. The orange pigment is recommended to be used for the coloration of paints and plastics, especially for the mass coloration of polyethylene. 

Thio-2-oxoselenazolidine can be obtained in 89% yield by treating the 2,4-dione with P4SJ0 in boiling dioxane (81). This structure is found in heterocyclic indigo-type dyes (Scheme 78). 

Hsynthesis from, 3, 767 Indenobenzazepines pharmacological properties, 7, 546 Indenone oxide, 2,3-diphenyl-photochromic compound, 1, 385 In deno[ 1,2-c][ 1,2,4]triazines synthesis, 3, 434 Indicated hydrogen nomenclature, 1, 33 Indigo, I, 317, 318-319, 4, 370 Baeyer synthesis, 1, 319 colour and constitution, 1, 344-345 molecular structure, 4, 162 photochromic compound, 1, 386 synthesis, 4, 247 Indigoid dyes... 

In order to explain the results shown in Fig. 2., the solution pH as a function of time was measured by a pH meter, and the results are displayed in Fig. 3. As can be seen from the data in the figure, when the initial solution pH is over 3.0, as reaction time increases, the solution pH decreases very fast to around 3.5 within 10 minutes, then reaches a lowest value of around 3.2 at 60 minutes, followed by a slight increase. What causes this interesting phenomenon We believed that the rapid decrease in solution pH is due to the fact that acidic intermediates are formed during the mineralization of 0.2 mM Indigo Carmine. Because of its complicated molecular structure, theoretically, it caimot be oxidized completely into CO2 and H2O in one step. 

Indigo is the most important vat dye, dating back to ancient times and produced on an industrial scale since 1880. To replace the indigo dyes, the indanthrone (21) class of dyes was developed. Indanthrone has superior characteristics as a vat dye and became a key material for further development of anthraquinoid vat dyes. There exist a variety of anthraquinone vat dyes differing in the chromophoric system. The color-structure relationship of vat dyes have been rationalized by the Pariser-Parr-Pople molecular orbital (PPP MO) method. Some examples of commercialized anthraquinoid vat dyes are shown in Scheme 6.14... 

Figure 5.7.1 The molecular structure of the water-insoluble dye indigo (2-(l,3-dihydro-3-oxo-2H-indol-2-ylidene)-l,2-dihydro-3H-indol-3-one).

Compound 9 when treated with KOH/MeOH gave 2,2 -bis-indole 170, a structural element present in indigo dyes in 89% yield (Scheme 21) <1995T5631>. 

As a class, these compounds are related to indigo, which is the oldest of all vat dyes. Indigo itself, during its comparatively short history as a commercial pigment, was used especially in rubber. Its structure was first described in 1883 by A.V. Bayer. Knowledge of this structure, together with the development of an industrial scale synthesis, facilitated the development of a series of indigo-based colorants. 

Both HPLC and GC-MS were employed for the separation, identification and quantitation of the decomposition products of indigo and indigo carmine. The chemical structures of the dyes are shown in Fig. 3.73. Carboxylic acids were preconcentrated before HPLC analysis either by ion-exchange SPE or by solid-phase microextraction. HPLC measurements were performed in a Sarasep column (300 X 7.8 mm i.d.) using 5 mM H2S04 at a flow rate of 0.7 ml/min. Analytes were detected at 215 nm. The main intermediates formed during the photocatalytic decomposition are compiled in Table 3.26. The results demonstrated that... 

Once the structure of indigo was established in 1870, it was quite logical to attempt its synthesis, not only as an intellectual challenge, but also as a profitable source of cheaper indigo that could advantageously compete with the natural dyestuff. The first industrial synthesis used by "Badische Anilin und Soda Fabrik" (BASF) was the procedure developed by Karl Neumann, which utilised the reaction of aniline with chloroacetic acid and then cyclisation of the resulting product to indoxyl promoted by NaNHj at high temperatures (over 200 °C). However, the... 

A pair of jeans with an overlay of the structure of indigo dye. 

Hubbard B, Kuang W, Moser A, Facey GA, DeteUier C (2003) Structural study of maya blue textural, thermal and solid-state multinuclear magnetic resonance characterization of the palygroskite-indigo and sepioUte-indigo adducts. Clays Clay Miner 51 318-326. 

Pour an indigo solution into a beaker, lower the end of an ozonizer gas discharge tube into it, and pass a weak stream of oxygen through the ozonizer. What happens What properties does ozone have What is the structure of an ozone molecule ... 

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