Nitro-sulfo

Electron-attracting substituents in the coupling components such as halogen, nitro, sulfo, carboxyl, and carbonyl, are deactivating and tend to retard coupling. 

Coupling with phenols is usually effected more easily than coupling with amines, and naphthols couple considerably more readily than hydroxybenzene derivatives. Reactive methylene compounds behave similarly to phenols of the benzene series. Negative substituents (halogen, nitro, sulfo, carboxyl, carbonyl, etc.) accelerate coupling when... 

Benzofurazan, 7-chloro-4-nitro-, 6, 394 as fluorigenic agents, 6, 410, 426 Benzofurazan, 4-chloro-7-sulfo-ammonium salt properties, 6, 426 Benzofurazan, 4-nitro-synthesis, 6, 408 Benzofurazans, 6, 393-426 Beckmann fragmentation, 6, 412 biological activity, 6, 425 bond angles, 6, 396 bond lengths, 6, 396 diazo coupling, 6, 409 dipole moments, 6, 400 electrochemical reduction, 5, 73 electrophilic reactions, 6, 409-410 ESR spectroscopy, 6, 400... 

The most common indirect nitration method, often used in nitrating phenols, consists of sul-forating the compd and then replacing the sulfo group by a nitro group. The usual nitrating agent for these reactions is coned nitric acid... 

Sulfo-SAND, SANPAH, and Sulfo-SANPAH all contain a nitrated phenyl azide photoreactive group. The presence of the nitro group shifts the optimal wavelength for photoactivation... 

The addition of C-centered radicals to the C=N bond giving rise to radicals B (Scheme 3.98) can be used for organization of radical C-alkylation of primary nitro compounds containing the sulfo group at the a-position (315). 

Synonyms 2,4-DNP Aldifen Chemox PE Dinofan Fenoxyl Carbon N Maroxol 50 Caswell No. 392 Sulfo Black B Nitro Kleenup... 

The most advantageous 2-pyridinecarbaldehyde derivative proved to be the acetal (example 3, Table 9) although, unlike the oxime, it was not commercially available. The acetal also usually afforded crystalline intermediate salts (181 Z = 0(CH2)20), but in addition made possible for the first time high temperature cyclization in PPA, permitting cyclization to rings deactivated by a nitro (example 25) or sulfo group (example 24). 

Neben Oxiranen oder 2-Oxo-l,3-dioxolan werden zur N-Alkylierung von Imidazolen manch-mal auch andere Heterocyclen verwendet, die in der Lage sind, unter Ringoffnung Nukleophile zu addieren. So kann 2-Methyl-4(5)-nitro-imidazol mit l,2-Oxathiolan-2,2,-dioxid (Propansul-ton) zu 2-Methyl-5-nitro-l-(3-sulfo-propyl)-imidazol (48%) und mit 2-Oxo-oxetan zu l-(2-Carboxy-ethyl)-2-methyl-4-nitro-imidazol umgesetzt werden875. 

Die Kinetik der Kupplung von 4-Nitro-phenyldiazonium-SaIzen in Gegenwart von Oberfliichen-aktiven Substanzen wurde untcrsucht1. Die Reaktionen von 2-Hydroxy- und 2-Hydroxy-6-sulfo-naphthalin waren mit 4-[(Dimethyl-hexadecyl-ammoniono)-methyl]-phenyldiazonium-dibromid t22 bzw. 244mal schneller (pH = 7) als mit der Vergleichsverbindung 4-(Dimethylamino-methyl)-phcnyldiazoniumbromid2. 

The nitration of l,2-diphenyl-3,5-dioxopyrazolidine with mixed acid at 0°C gives the 4-nitro derivative, whereas sulfonation (20% oleum) results in both 4- and phenyl substitution to form 4-sulfo-l,2-bis (4-sulfophenyl)-3,5-dioxopyrazolidine (58ZOB3027). 

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