Benzo-purple

The statement so often met with in the literature that the precipitation of these finer suspensions is irreversible, as in the case of colloidal metals, is quite false. Schlosing has demonstrated that after the removal of the electrolyte the clay may be returned to its original suspended form. In this regard turbid clay solutions resemble hydro-phile colloids (reversible) much more than they do metal hydrosols, and from the properties of the precipitate should be classed with the former rather than with the latter. The similarity between turbid solutions of clay and metal hydrosols exists almost exclusively in the sensitivity of both toward electrolytes. This sensitivity, however, they have in common with certain ionogen disperse solutions such as Congo-red and Benzo-purple. 

Benzo[ >]thiophene dianion (173) has been prepared by reduction of benzo[ >J thiophene with sodium metal at - 78°C in [2H8]THF. The H and 13C NMR spectra of the purple solution obtained prove that it is the dianion and not a radical anion. This is the first example of a sulfur-containing (4n)Tr polycyclic dianion. The dianion undergoes oxidation to benzo[ ]thiophene with oxygen (85CC1033). 

Violets and heliotropes of the benzo, benzoform, bnlliant Congo, chloramine, chlorazol, Columbia, diamme, diaml, dianol, diazo, diphenyl, direct, formal, naphthamine, oxamme, oxydiamme, para, rosantbrene, tnsulphon, etc, senes Azo marne, azo violet, benzo fast heliotrope, chlorantme lilac, hessian purple V-olet ... 

Herz et al.hli assigned to the yellow adduct of levopimaric acid (1) and 1,4-benzo-quinone the structure (2) and found that a solution of 5 g. of (2) in 75 ml. of /-butanol treated with a solution prepared from 0.7 g. of potassium and 50 ml. of /-butanol and then with a stream of oxygen for 3 hrs. developed a deep purple color. Addition of 60 ml. of water and removal of the solvent left a purple residue from which by acidification, solvent extraction, and chromatography a hydroxyquinone (3) was isolated in 20% yield. A distinction was not made between the two possible positions for the hydroxyl group. 

If 1,5-difluoro-2,4-dinitrobenzene is used as the activated halogen compound, then in boiling DMF solution a double ring-closure to the tetraphenyl-17/,9//-benzo[l,2-c 5,4-e ]bi-s[l,3,4]thiadiazine (294) (14%) is noted. 2,4-Dinitrofluorobenzene also undergoes reaction with dithizone (PhN=NCSNHNHPh) in acetonitrile at 25 °C to yield 6-nitro-l-phenyl-3-phenylazo-l//-4,l,2-benzothiadiazine (293) as purple needles in 79% yield (see also Section 6.17.7.1.3). 

Benzo[(>]thiophene dianion has been prepared by reduction of benzo[(>]thiophene with sodium metal at — 78 C in pHgjTHF. The H and C NMR spectra of the purple solution obtained prove... 

Hexamethylphosphorio triamide, supplied by Eisher Scientific Company, was purified by distillation from sodium (approximately 6 g. per 500 ml.). The boiling point was 69° (1 mm.). In place of hexa-methylphosphoric triamide, tetrahydrofuran can be used, and 120 ml. of this solvent was slowly added over 30 minutes through a stainless steel cannula. Mallinckrodt analytical-reagent tetrahydrofuran was purified by distillation from a dark purple solution of disodium benzo-phenone dianion under nitrogen before use. The checkers used only hexamethylphosphorio triamide (see p. 103 for warning). 

Hose JE, Puffer HW (1983) Cytologic and cytogenetic anomalies induced in purple sea urchin embryos (Strongylocentrotus purpuratus S.) by parental exposure to benzo(a)pyrene. Mar Biol Lett 4 87-95... 

Hose JE, Puffer HW, Oshida PS, Bay SM (1983) Development and cytogenetic abnormalities in the purple sea urchin by environmental levels of benzo(a)pyrene. Arch Environ Contam Toxicol 12 319-325... 

Benzo [a] triphenylene 687 Bis[(aminocarbonyl)amino]aceticacid 156 Bromcresol Purple 1157... 

To benzo[A]quinolinyl palladium(II) pyridine-sulfonamido complex (12.8 mg, 0.0200 mmol) in acetonitrile-c/i (0.6 mL) at 23 °C was added l-chloromethyl-4-fluoro-l,4-diazoniabicyclo [2.2.2]octane bis(tetrafluoroborate) (7.1 mg, 0.020 mmol). After stirring for 10 min at 23 °C, the colorless suspension formed a dark purple solution. The complex was characterized by nuclear magnetic resonance (NMR spectroscopy) in acetonitrile solution without purification. ... 

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