ChemicalBook CAS DataBase List 2-Aminobenzothiazole-6-carboxylic acid

2-Aminobenzothiazole-6-carboxylic acid synthesis

13synthesis methods

Product Name:2-Aminobenzothiazole-6-carboxylic acid
CAS Number:93-85-6
Molecular formula:C8H6N2O2S
Molecular Weight:194.21

540-72-7

150-13-0

93-85-6

Steps for the synthesis of 2-aminobenzothiazole-6-carboxylic acid: (2) Sodium thiocyanate (NaSCN, 65 g, 0.8 mol) was added to a methanol (MeOH) suspension of 4-aminobenzoic acid (1,100 g, 0.73 mol), followed by batch addition of bromine (Br2, 38 mL, 0.73 mol). The reaction mixture was cooled to -10 °C and stirred for 2 hours while keeping the internal temperature below -5 °C. Upon completion of the reaction, the precipitate was collected by filtration and suspended in 350 ml of 1 M hydrochloric acid (HCl). The suspension was heated to reflux and maintained for 30 minutes. After rapid filtration, 150 ml of concentrated hydrochloric acid (HCl) was added to the hot filtrate to give 70 g (42% yield) of 2-aminobenzothiazole-6-carboxylic acid (white solid). The product was dried and used directly without further purification.

540-72-7 Synthesis

540-72-7
476 suppliers
$13.50/100G

150-13-0 Synthesis

150-13-0
956 suppliers
$5.00/25g

93-85-6
151 suppliers
$7.00/250mg

Yield:93-85-6 42%

Reaction Conditions:

with bromine in methanol at -10 - -5; for 2 h;

Steps:

1
Synthesis of 2-aminobenzothiazole-6-carbolic Acid(2)NaSCN (65 g, 0.8 mol) was added to a suspension of commercially available 4-amino-benzoic acid (1, 100 g, 0.73 mol) in MeOH followed by the addition of Br₂(38 ml, 0.73 mol) in portions. The above solution was allowed to cool to -10° C. and stirred for 2 h while keeping the inner temperature below -5° C. The precipitate was then filtered and suspended in 350 ml of 1 M HCl. The suspension was heated to reflux for 30 min. After immediate filtration, 150 ml concd HCl was added to the hot filtrate to give 70 g (yield 42%) of 2-amino-benzothiazole-6-carboxylic acid (2) (as a white solid), which was dried and used without further purification.

References:

WANG, YANMING;Wu, Chunying US2009/123373, 2009, A1 Location in patent:Page/Page column 14-15

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68867-21-0 Synthesis