2-Amino-6-bromobenzothiazole

white to light yellow crystal powde

A solution of substituted aniline (2 mmol) in acetonitrile (15 ml) was added to a solution of KSCN (8 mmol) in acetonitrile (15 ml). Then, 0.06 g (30 mol percent BFA solution of 4-bromoaniline (0.500 g, 2.91 mmol) and potassium thiocyanate (1.13 g, 11.6 mmol) in AcOH (10 ml) was stirred at 20 °C for 10 min. Bromine (150 μl, 2.91 mmol) was added over 20 min to the above solution. The reaction mixture was stirred further at room temperature for 60 min. On completion of reaction following a TLC examination, the reaction mixture was poured into a solution of NHGeneral procedure: A mixture of 0.1 mol of 4-substituted aniline and 0.1 mol of Potassium thiocyanate (KCNS) in 100 ml glacial acetic acid (AcOH) was cooled in an ice bath and stirred for 10-20 min, and then 0.1 mol bromine in glacial acetic acid was added dropwise at such a rate to keep the temperature below 10 °C throughout the addition. The reaction mixture was stirred at room temperature for 2-4 h, the hydrobromide (HBr) salt thus separated out was filtered, washed with acetic acid, dried, dissolved in hot water and basified to pH 11.0 with ammonia solution (NHGeneral procedure: A mixture of 0.1 mol of 4–substituted aniline and 0.1 mol ofPotassium thiocyanate (KCNS) in 100 ml glacial acetic acid (AcOH) was cooled inan ice bath and stirred for 10 to 20 min, and then 0.1 mol bromine in glacialacetic acid was added dropwise at such a rate to keep the temperature below 10C throughout the addition. Theprogress of the reaction was monitored by Thin Layer Chromatography usingtoluene: acetone (8:2) solvent system. The reaction mixture was stirredat room temperature for 2 to 4 hrs, the hydrobromide (HBr) salt thus separatedout was filtered, washed with acetic acid, dried, dissolved in hot water and basified to pH 11.0 with ammonia solution (NHGeneral procedure: An appropriately p-substituted aniline (0.1 mol) and potassiumthiocyanate (KCNS, 9.718 g, 0.1 mol) were dissolvedin 100 mL of glacial acetic acid (AcOH), cooled inice–salt mixture and stirred mechanically, while a solutionof bromine (15.980 g, 0.1 mol) in AcOH (20 mL)was slowly added drop by drop (Palkar et al. 2010).External cooling was applied throughout the process to keepthe temperature below 10 °C and the stirring was continuedfor 30 min. After all of the bromine had been added, thesolution was stirred for 2 h below room temperature and atroom temperature for 10 h. It was then allowed to standovernight during which the precipitate of imino-benzo[d]thiazole hydrobromide salt thus separated out was filtered, washed with acetic acid, dried, dissolved in hot water andbasified to pH 11.0 with ammonia solution (NH4OH) andthe resulting precipitate was filtered, washed with water anddried to get the desired products 2-amino-6-substitutedbenzo[d]thiazole (1a–d). The progress of the reaction wasmonitored by TLC using acetone (20percent) in toluene solvent.General procedure: A solution of bromine (0.26mL, 10.0mmol) in acetic acid (5.0mL)was added over about 30 min to a mixture of aromatic amine(10.0 mmol) and potassium thiocyanate (1.07 g, 11.0 mmol) in aceticacid (20 mL), the temperature being kept between 25 and 35 °C. The slurry was then stirred for 20 h at room temperature. The precipitate was filtered, washed with a little acetic acid, slurried in water, made neutral with aqueous ammonia, and filtered again. The residue was boiled for 20 min with excess of hydrochloric acid (15percent v:v) and the hot mixture was filtered from impurities. The filtrate, cooled to 10 °C, was made alkaline with aqueous ammonia and the precipitate was filtered, washed, and dried. The crude product was recrystallized from ethanol–water to afford I–IV, respectively.4-Bromoaniline (I−1) (120 g, 0.697 mol) and KSCN (69 g, 0.697 mol) were dissolved in a mixture of THF (500 mL) and AcOH (450 mL). The mixture was stirred at RT for 30 min. and then was cooled to −30° C., solid NBS (124 g, 0.697 mol) was added slowly. The resulting mixture was stirred at −30° C. for 30 min., and then was allowed to warm to RT and stirred overnight. The solution was poured into stirred ice-water (3000 mL), ammonia solution was added to adjust the pH value to 9 and then filtered. The filtrate was extracted with ethyl acetate (2000 mL), washed with water (500 mL), dried over NaGeneral procedure: A mixture of aniline (0.05mol) and NH

Molecular Weight:229.10
XLogP3:2.9
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:227.93568
Monoisotopic Mass:227.93568
Topological Polar Surface Area:67.2
Heavy Atom Count:11
Complexity:155
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes