Реакция #53591

Уравнение реакции

7-amino-1-hydroxy-3-naphthalene sulfonic acid

sodium hydrosulfite

HCl

sodium sulfanilate

sodium nitrite

→

title compound

Выход 45.0%

7,8-Diamino-1-hydroxy-3-naphthalene sulfonic acid dihydrochloride

Выход 45.0%

Растворители

water

water

Условия реакции

Обработка

1. 1
   ТемператураThe reaction mixture was warmed to 50° C.
2. 2
   workup.STIRRINGthe reaction was stirred for 4 hours
3. 3
   ФильтрацияThe reaction was filtered
4. 4
   Промывкаthe precipitate was washed with water, methanol, and ether

Методика

A stirred solution of p-benzenediazonium sulfonic acid, was prepared by the addition of sodium sulfanilate (1.10 g, 5.2 mmole) to sodium nitrite (0.40 g, 5.7 mmole) in water (10 mL) followed by addition to ice (6.0 g) and concentrated HCl (1.1 mL, 37%). After 30 min. of standing at 0° C. 7-amino-1-hydroxy-3-naphthalene sulfonic acid (1.2 g, 5.2 mmole) was added in water (10 mL) and the reaction was stirred at room temperature overnight. The reaction mixture was warmed to 50° C. and sodium hydrosulfite (3.0 g, 15.6 mmole) was added and the reaction was stirred for 4 hours. The reaction was filtered and the precipitate was washed with water, methanol, and ether to give the title compound (0.54 g; 45%) as a red solid. MS(ES) m/z 255 [M+H].

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