ChemicalBook CAS DataBase List 2-Amino-6-nitrobenzothiazole

2-Amino-6-nitrobenzothiazole synthesis

11synthesis methods

Product Name:2-Amino-6-nitrobenzothiazole
CAS Number:6285-57-0
Molecular formula:C7H5N3O2S
Molecular Weight:195.2

333-20-0

100-01-6

6285-57-0

GENERAL METHOD: A solution of 4-nitroaniline (2 mmol) in acetonitrile (15 ml) was slowly added to a solution of potassium thiocyanate (8 mmol) in acetonitrile (15 ml). Subsequently, 0.06 g (30 mol%) of BF3/SiO2 nanocatalyst was added to the reaction system and the mixture was placed in an ice salt bath and mechanically stirred for 30 min. A solution of bromine (4 mmol, 0.2 ml) in acetonitrile (3 ml) was slowly added through a dropping funnel, and the dropping rate was controlled to ensure that the reaction temperature did not exceed 0 °C. After the addition of the bromine solution, the reaction continued to be stirred at room temperature for 4 h, during which the progress of the reaction was monitored by TLC. Upon completion of the reaction, the reaction mixture was poured into water, heated in a 70 °C water bath and thermally filtered to remove the catalyst. The catalyst was washed with acetone and recycled for reuse. The filtrate was neutralized to neutrality with 10% NaOH solution and the precipitated solid was collected by filtration, dried and recrystallized with ethanol (10 ml) to give the target product 2-amino-6-nitrobenzothiazole. The structure of the product was confirmed by the following physical and spectral data and verified by comparison with standards. Spectral data of 2-amino-6-nitrobenzothiazole: yellow solid; yield = 93%; melting point = 202-204 °C (literature value 203 °C); FT-IR (KBr, cm^-1): 3315, 3012, 2835, 1580, 1476, 1261, 920, 742, 512; ^1H NMR (400 MHz, CDCl3 , δ ppm): 5.44 (s, 2H, NH2), 7.4-7.5 (d, 2H, Ar-H), 7.71 (s, 1H, Ar-H); ^13C NMR (100 MHz, DMSO-d6, δ ppm): 119, 120.9, 125.15, 126.07, 133.1, 152.15, 167.75.

136-95-8 Synthesis

136-95-8
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6285-57-0
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$9.00/1g

Yield:6285-57-0 80%

Reaction Conditions:

with sulfuric acid;nitric acid at 5 - 20; for 3 h;

Steps:

6-Nitrobenzothiazol-2-amine (2). 2-Aminobenzothiazole, 0.157 mol, was dissolved in 36 mL of sulfuric acid under cooling (< 5°C) and vigorous stirring, after which 19 mL of nitric acid was added dropwise so that the temperature of the reaction mixture was maintained at 20°C. After 3-h stirring, the reaction mixture poured onto ice while being stirred continuously, and aqueous ammonia was added until the solid product turned slightly orange. It was filtered off, washed with excess water, dried, and recrystallized from ethanol. Yield 80%, mp 150-152°C. IR spectrum, ν, cm-1: 3385, 3311 (NH2), 1525, 1342 (NO2), 1284 (C-N), 744 (C-S). Found, %:C 43.22; H 2.33; N 21.09; S 16.76. C7H5N3O2S. Calculated, %: C 43.07; H 2.58; N 21.53; S 16.43.

References:

Abbas, S. K.;Abbas, Z. F.;Hanoon, H. D.;Hussein, K. A.;Radhi, S. M. [Russian Journal of Organic Chemistry,2020,vol. 56,# 2,p. 327 - 331][Zh. Org. Khim.,2020,# 2]

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333-20-0
464 suppliers
$13.50/100G

100-01-6
89 suppliers
$11.19/25G

6285-57-0
209 suppliers
$9.00/1g

References