Benzothiazole,2-chloro-5-nitro-(7CI,8CI,9CI)

General procedure: GP3-1: A solution of 2-halo substituted aniline (1.0 eq), potassium ethyl xanthate (1.2 eq or 2.2 eq, typically 2.2 eq) in 10 volume of anhydrous DMF was heated at 100 Solid 5-nitrobenzo[d]thiazole-2-thiol (4.0 g, 18.8 mmol) was placed in a round bottom flask and cooled to 0°C while S0To a solution of 2-CHLOROBENZOTHIAZOLE (12.0 g, 70.7 MMOL) in concentrated H2SO4 (60 mL) was added HN03 (69percent solution, 6 mL) dropwise at 0°C for 20 min. The mixture was stirred at 5°C for 3h, poured into ice-water (150 mL). The precipitate was collected and washed with 5percent sodium bicarbonate and water, dried in VACUO.APOS;H NMR analysis showed the mixture contained 78percent 6-nitro-2-chlorobenzothiazole and 8percent 5-nitro-2- chlorobenzothiazole. Recrystallization from ethanol gave 6-nitro-2-chlorobenzothiazole as white crystalline solid (11 g, 72percent). 3.5 g of the solid was dissolved in refluxing ethanol-acetic acid (150: 15 mL), Iron powder was added in one portion.. The mixture was refluxed for 1.5h, filtered. The filtrate was concentrated in vacuo to half volume and neutralized with 10percent NaOH to pH 7.5, extracted with ethyl acetate. The organic phase was washed with brine, dried over magnesium sulphate and evaporated to give a residue, which was RECRYSTALLIZED from ethanol. Light purple crystals (2.5 g, 83percent) were obtained. Mp 160-164°C ; TLC single spot at Rf 0.27 (30percent EtOAc/hexane) ;APOS;HNMR (270 MHz, DMSO-d6) 5 7.58 (1H, d, J = 9.0 Hz, 4-H), 7.03 (1H, d, J = 2.0 Hz, 7-H), 6.77 (1 H, dd, J = 9.0, 2. 0 Hz, 5-H), 5.55 (2H, s, NH2). The mother liquor from the RECRYSTALLIZATION of nitration product was evaporated and subjected to iron powder reduction as described above. The crude product was purified with flash chromatography (ethyl acetate-DCM gradient elution) to give 2-CHLORO- benzothiazol-5-yl-amine as yellow solid. Mp 146-149°C ; TLC single spot at Rf 0.52 (10percent EtOAc/DCM) ;APOS;HNMR (270 MHZ, DMSO-d6) 8 7.63 (1 H, d, J = 8. 6 HZ, 7-H), 7.05 (1 H, d, J = 2.3 Hz, 4-H), 6.78 (1 H, dd, J = 8.6, 2.3 Hz, 6-H), 5.40 (2H, s, NH2).General procedure: GP3-1: A solution of 2-halo substituted aniline (1.0 eq), potassium ethyl xanthate (1.2 eq or 2.2 eq, typically 2.2 eq) in 10 volume of anhydrous DMF was heated at 100 0Cor 120 0C for 4 hours under nitrogen. TLC monitored the progress ofreaction. After completion, the reaction mixture was cooled to room temperature, diluted with water (10 volume) and neutralized by 1 M HCl solution to pH 5. Theformed precipitate was collected by filtration, rinsed with water, firstlydried by rotavapor, and then dried by oil pump to afford 2-mercaptobenzothiazole.GP3-2: 2-mercaptobenzothiazole in 10 volume ofanhydrous DCM, was added by sulfuryl chloride (SO2Cl2, 1volume) under ice-cooled condition. The mixture was stirred at rt for 1 hour, which was monitored by TLC. After consumption of starting material, the mixturewas diluted by 30 volume of ether, following quenching carefully by addingwater. Stirring was kept for 1 hour to make sure the SO2Cl2was totally consumed and product was released. Organic layer was collected, neutralized by saturated NaHCO3, dried over Na2SO4and purified by silica gel chromatograph to give the pure product, which wasfinally characterized by LC-MS and NMR.Solid 5-nitrobenzo[d]thiazole-2-thiol (4.0 g, 18.8 mmol) was placed in a round bottom flask and cooled to 0C while S02CI2(9.1 mL, 1 13 mmol) was slowly added at 0C. Upon complete additions, the yellow suspension was stirred at 0C for 5 min, then at rt for 2 h. The mixture was poured onto ice/water (200 mL) and stirred for 1 h. The precipitate that formed was collected, washed with water and dried under high vacuum. The material was slurried in EA (25 mL), vigorously stirred for 15 min and filtered. The filtrate was concentrated and dried. The obtained solid absorbed to silica gel and purified by CC eluting with heptane:EA 4:1 to give the title compound (2.02 g) as a solid; LC-MS: tR= 0.84 min; [M+H]+= 214.51 ;1H NMR (400 MHz, CDCI3) delta: 8.84 (d, J = 2.2 Hz, 1 H), 8.35 (dd, J, = 2.2 Hz, J2= 8.9 Hz, 1 H), 7.98 (d, J = 8.9 Hz, 1 H).General procedure: GP3-1: A solution of 2-halo substituted aniline (1.0 eq), potassium ethyl xanthate (1.2 eq or 2.2 eq, typically 2.2 eq) in 10 volume of anhydrous DMF was heated at 100 0Cor 120 0C for 4 hours under nitrogen. TLC monitored the progress ofreaction. After completion, the reaction mixture was cooled to room temperature, diluted with water (10 volume) and neutralized by 1 M HCl solution to pH 5. Theformed precipitate was collected by filtration, rinsed with water, firstlydried by rotavapor, and then dried by oil pump to afford 2-mercaptobenzothiazole.GP3-2: 2-mercaptobenzothiazole in 10 volume ofanhydrous DCM, was added by sulfuryl chloride (SO2Cl2, 1volume) under ice-cooled condition. The mixture was stirred at rt for 1 hour, which was monitored by TLC. After consumption of starting material, the mixturewas diluted by 30 volume of ether, following quenching carefully by addingwater. Stirring was kept for 1 hour to make sure the SO2Cl2was totally consumed and product was released. Organic layer was collected, neutralized by saturated NaHCO3, dried over Na2SO4and purified by silica gel chromatograph to give the pure product, which wasfinally characterized by LC-MS and NMR.Solid 5-nitrobenzo[d]thiazole-2-thiol (4.0 g, 18.8 mmol) was placed in a round bottom flask and cooled to 0°C while S02CI2(9.1 mL, 1 13 mmol) was slowly added at 0°C. Upon complete additions, the yellow suspension was stirred at 0°C for 5 min, then at rt for 2 h. The mixture was poured onto ice/water (200 mL) and stirred for 1 h. The precipitate that formed was collected, washed with water and dried under high vacuum. The material was slurried in EA (25 mL), vigorously stirred for 15 min and filtered. The filtrate was concentrated and dried. The obtained solid absorbed to silica gel and purified by CC eluting with heptane:EA 4:1 to give the title compound (2.02 g) as a solid; LC-MS: tR= 0.84 min; [M+H]+= 214.51 ;1H NMR (400 MHz, CDCI3) delta: 8.84 (d, J = 2.2 Hz, 1 H), 8.35 (dd, J, = 2.2 Hz, J2= 8.9 Hz, 1 H), 7.98 (d, J = 8.9 Hz, 1 H).o a solution of General procedure: GP3-2: 2-mercaptobenzothiazole in 10 volume of anhydrous DCM, was added by sulfuryl chloride (SO2Cl2, 1 volume) under ice-cooled condition. The mixture was stirred at rt for 1 hour, which was monitored by TLC. After consumption of starting material, the mixture was diluted by 30 volume of ether, following quenching carefully by adding water. Stirring was kept for 1 hour to make sure the SO2Cl2 was totally consumed and product was released. Organic layer was collected, neutralized by saturated NaHCO3, dried over Na2SO4 and purified by silica gel chromatograph to give the pure product, which was finally characterized by LC-MS and NMR.; 2-chloro-7-fluorobenzothiazole The title compound was prepared according to GP3-2, which was purified by flash column chromatography using PE/EA (20/1) as eluent to give the colorless oil. (420 mg, 22percent yield) 1H NMR (400 MHz, CDCl3) delta 7.76 (d, J=8.2 Hz, 1H), 7.45 (td, J=8.1, 5.9 Hz, 1H), 7.14 (t, J=8.7 Hz, 1H). 13C NMR (101 MHz, CDCl3) delta 156.11 (d, J=250.1 Hz), 154.27, 153.45 (d, J=2.8 Hz), 127.63 (d, J=7.3 Hz), 123.25 (d, J=17.6 Hz), 118.80 (d, J=3.7 Hz), 111.41 (d, J=18.3 Hz).Step: 100 mg, 0.67 mmol of benzo[c][1, 2]oxaborol-1, 5(3H)-diol was dissolved in 8 mL of acetonitrile.Then, 172 mg, 0.8 mmol of

Molecular Weight:214.63
XLogP3:3.4
Hydrogen Bond Acceptor Count:4
Exact Mass:213.9603762
Monoisotopic Mass:213.9603762
Topological Polar Surface Area:87
Heavy Atom Count:13
Complexity:223
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes