5-Bromo-2-mercaptobenzothiazole

Yellow solid

5-bromobenzothiazole 214.08 mg (1.0 mmol), 1, 3-propanedithiol 325 μL (3.0 mmol), potassium carbonate552mg (4.0mmol) and 2mL DMSO, placed in a reaction tube equipped with a magnetic stirrer, sealed with nitrogen, heated and stirred, The reaction was carried out in an oil bath at 120 ° C for 12 hours. After the reaction is completed, the reaction solution is transferred to a separatory funnel by washing with water, and an appropriate amount is added. Dilute hydrochloric acid, adjust the pH of the aqueous phase to 1-3, and extract the organic phase with dichloromethane, and transfer the upper organic phase with anhydrous magnesium sulfate. dry. Steam distillation under reduced pressure and separation by column chromatographyThe pink solid product was 112.4 mg, yield 45.7percent.Step A: 5-Bromobenzothiazole-2-thiol; To a solution of 5-bromo-2-fluorobenzenamine (200 mg, 1.28 mmol) in N-methyl-2- pyrrolidine (1.5 mL) was added potassium o-ethyl carbonodithioate (410 mg, 2.56 mmol). The mixture was heated at 140 General procedure: To a solution of benzothiazoles or benzoxazoles (1, 1 mmol) in DMSO (3 mL), was added KOH (280 mg, 5 equiv) and 1, 3-propanedithiol (207 μL, 2 mmol). The reaction mixture was heated under argon at 130 °C for 12 h. After cooling to room temperature, water (10 mL) was added. The pH of the reaction mixture was adjusted to 3–4 using 5percent HCl. The resulting mixture was extracted with ethyl acetate (15 mL ×2). The organic layer was washed with water and brine, dried over anhydrous MgSO4 and concentrated using rotary evaporator. The crude product was purified by silica gel column chromatography using ethyl acetate/n-hexane as eluent to afford the corresponding heteroaryl thiols 3.5-bromobenzothiazole 214.08 mg (1.0 mmol), 1, 3-propanedithiol 325 μL (3.0 mmol), potassium carbonate552mg (4.0mmol) and 2mL DMSO, placed in a reaction tube equipped with a magnetic stirrer, sealed with nitrogen, heated and stirred, The reaction was carried out in an oil bath at 120 ° C for 12 hours. After the reaction is completed, the reaction solution is transferred to a separatory funnel by washing with water, and an appropriate amount is added. Dilute hydrochloric acid, adjust the pH of the aqueous phase to 1-3, and extract the organic phase with dichloromethane, and transfer the upper organic phase with anhydrous magnesium sulfate. dry. Steam distillation under reduced pressure and separation by column chromatographyThe pink solid product was 112.4 mg, yield 45.7percent.Step A: 5-Bromobenzothiazole-2-thiol; To a solution of 5-bromo-2-fluorobenzenamine (200 mg, 1.28 mmol) in N-methyl-2- pyrrolidine (1.5 mL) was added potassium o-ethyl carbonodithioate (410 mg, 2.56 mmol). The mixture was heated at 140 General procedure: To a solution of benzothiazoles or benzoxazoles (1, 1 mmol) in DMSO (3 mL), was added KOH (280 mg, 5 equiv) and 1, 3-propanedithiol (207 muL, 2 mmol). The reaction mixture was heated under argon at 130 C for 12 h. After cooling to room temperature, water (10 mL) was added. The pH of the reaction mixture was adjusted to 3-4 using 5% HCl. The resulting mixture was extracted with ethyl acetate (15 mL ×2). The organic layer was washed with water and brine, dried over anhydrous MgSO4 and concentrated using rotary evaporator. The crude product was purified by silica gel column chromatography using ethyl acetate/n-hexane as eluent to afford the corresponding heteroaryl thiols 3.5-bromobenzothiazole 214.08 mg (1.0 mmol), 1, 3-propanedithiol 325 muL (3.0 mmol), potassium carbonate552mg (4.0mmol) and 2mL DMSO, placed in a reaction tube equipped with a magnetic stirrer, sealed with nitrogen, heated and stirred, The reaction was carried out in an oil bath at 120 C for 12 hours. After the reaction is completed, the reaction solution is transferred to a separatory funnel by washing with water, and an appropriate amount is added. Dilute hydrochloric acid, adjust the pH of the aqueous phase to 1-3, and extract the organic phase with dichloromethane, and transfer the upper organic phase with anhydrous magnesium sulfate. dry. Steam distillation under reduced pressure and separation by column chromatographyThe pink solid product was 112.4 mg, yield 45.7%.Step-1 : Step A: 5-Bromobenzothiazole-2-thiol; To a solution of 5-bromo-2-fluorobenzenamine (200 mg, 1.28 mmol) in N-methyl-2- pyrrolidine (1.5 mL) was added potassium o-ethyl carbonodithioate (410 mg, 2.56 mmol). The mixture was heated at 140 0C for 2 h. The reaction mixture was poured into a large amount of water, acidified with concentrated hydrochloric acid, and filtered to give 5-bromo- benzothiazole-2-thiol 300 mg (95 %).Step B: 5-bromo-2-(methylthio)benzo[d]thiazole; To a solution of 5-bromobenzo[d]thiazole-2 -thiol (24 mg, 0.098 mmol) in EtOH (1.5 mL) was added triethylamine (10 mg, 0.098 mmol) and methyliodide (14 mg, 0.098 mmol). The mixture was heated at reflux for 1.5 h. Then the mixture was extracted with dichloromethane (3 x 10 mL). The combined organic extracts were washed with brine, dried (Na2SO4) and concen- trated to give 5-bromo-2-(methylthio)benzothiazole 20 mg (80 %).1H NMR (400 MHz, CDCI3): delta 8.02 (s, 1 H), 7.60 (d, 1 H), 7.39 (d, 1 H), 2.79 (s, 3 H).(iv)

Molecular Weight:246.2
XLogP3:3.1
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Exact Mass:244.89685
Monoisotopic Mass:244.89685
Topological Polar Surface Area:69.4
Heavy Atom Count:11
Complexity:185
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes