6-Chloro-2(3H)-benzothiazolethione

Yellow solid

General procedure: A 25 mL Wattecs reaction tube was charged with 2-haloaniline 1 (0.6 mmol), potassium O-ethyl dithiocarbonate 2 (1.8 mmol), CuCl (0.06 mmol), and DMF (2 mL). The reaction vessel was flushed with argon three times and sealed. Then the mixture was stirred electromagnetically in an oil bath at 110°C for 6 h.The reaction process was monitored by TLC on silica gel. After the reaction was completed, the reaction mixture was cooled to room temperature, and then HCl (3 mL, 3 mol/L) was added and stirred for another 30 min. The reaction mixture solution was extracted by ethyl acetate (3 × 20 mL). Subsequently, the combined organic solutions were dried by anhydrous sodium sulfate and the target product was purified by chromatography on a silica gel column (eluent: petroleum ether/ethyl acetate) togive the corresponding pure product 3. Complete characterization characterizationof the products (all known) is found in the Supplemental Materials (Figures S1–S13).General procedure: A 25 mL reaction tube was charged with 2-haloaniline 1 (0.6 mmol), potassium o-ethyldithiocarbonate 2 (1.8 mmol), FeF3 (0.06 mmol), 2, 2’-bis(diphenylphosphino)-1, 1’-binaphthyl (0.03 mmol) and DMF (4 mL). The reaction vessel was flushed with argon for three times and sealed. Then the mixture was stirred electromagnetically in an oil bath at 110 for 3 - 21 hours. The reaction process was monitored by TLC on silica gel. After the reaction was completed, the reaction mixture was cooled to room temperature, then 4 mL HCl (3mol/L) was added and stirred for 30 minutes. Then the reaction mixture solution was extracted by ethyl acetate (3*20 mL). Subsequently, the combined organic solution were dried by anhydrous sodium sulfate and the target product was purified by silica gel colum chromatography (eluent: petroleum ether / ethylacetate) to give the corresponding pure product 3.General procedure: A sealed tube (50 mL) was charged with 2-haloaniline 1a (2mmol), CSGeneral procedure: A sealed tube (50 mL) was charged with 2-haloaniline 1a (2mmol), CS127 mg (0.40 mmol) of 4, 4'-dichloro-2, 2'-dithiodiphenylamine and 11.2 mg (0.2 mmol) of NaHS were added to the reaction flask followed by the addition of 2.5 mL of H20 as a reaction solvent, Then injected into 97yL (l · 6mmol) of carbon disulfide, the reaction was stirred at 80 ° C for 4 hours after plate chromatography test found disulfide raw material reaction was complete, cooled to room temperature, extracted with ethyl acetate, and then using rotary evaporation The solvent was removed under reduced pressure to give the crude product. The crude product was eluted with methylene chloride and eluted with a gradient. After column chromatography (200-300 mesh silica gel), 122 mg of 6-chloro-2-mercaptobenzothiazole was obtained as a white powder with a purity of more than 99percent Isolated yield 75.6percent, mp 239-241.[Referential Example 145] 6-Chloro-2-mercaptobenzothiazole Under ice cooling, a solution of p-chloroaniline (5.70 g) in acetic acid (7 ml) was added dropwise to disulfur dichloride (25.0 ml) over 30 minutes, followed by stirring at room temperature for 3 hours and then at about 80C for 3 hours. Benzene (50 ml) was added to the reaction mixture. The green crystals were collected by filtration and washed with benzene. The resulting crystals were dissolved in ice water (500 ml) and the solution was stirred for 1 hour. To the reaction mixture, a 6N aqueous solution of sodium hydroxide was added to make the mixture alkaline. Sodium bicarbonate (6 g) was then added and the mixture was stirred at 100C for 1 hour. Activated carbon was added to the reaction mixture, followed by Celite filtration. To the filtrate, carbon disulfide (2.70 ml) was added, followed by heating to about 50C. Stirring was then conducted for 1.5 hours. After cooling to room temperature, the reaction mixture was made acidic with 1Nhydrochloric acid. Colorless powder thus precipitated was collected by filtration and dried, whereby the title compound (1.30 g, 14%) was obtained. 1H-NMR (DMSO-d6) delta: 7.28(1H, d, J=8.3Hz), 7.45(1H, dd, J=8.3, 2.0Hz), 7.86(1H, d, J=2.0Hz). MS (FAB) m/z: 202 [(M+H)+, Cl35], 204 [(M+H)+, Cl37]. Elementary analysis for C7H4ClNS2 Calculated: C, 41.68; H, 2.00; Cl, 17.58; N, 6.94; S, 31.80. Found: C, 41.64; H, 2.13; Cl, 17.83; N, 6.94; S, 31.70.EXAMPLE 1C A general procedure (the `Herz process`) for the preparation of 2-mercaptobenzthiazoles from the corresponding 2-mercaptoaniline (and a procedure for preparing the 2-mercaptoaniline from the corresponding aniline) is illustrated by the following preparation of 6-chloro-2-mercaptobenzthiazole.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.A mixture of N-(1H-benzimidazol-2-yl)-2-chloroacetamide(1) (2.39 mmol, 0.5 g), appropriate mercapto derivatives (3.20 mmol) and K2CO3 (2.39 mmol, 0.24 g) in acetone was stirred for 6 hours. At the end of the period, the solvent was vaporised and the residue was washed with water and filtered. After dryness, raw product was recrystallised from alcohol. Some chemical properties were given in Table 1.127 mg (0.40 mmol) of 4, 4'-dichloro-2, 2'-dithiodiphenylamine and 11.2 mg (0.2 mmol) of NaHS were added to the reaction flask followed by the addition of 2.5 mL of H20 as a reaction solvent, Then injected into 97yL (l · 6mmol) of carbon disulfide, the reaction was stirred at 80 C for 4 hours after plate chromatography test found disulfide raw material reaction was complete, cooled to room temperature, extracted with ethyl acetate, and then using rotary evaporation The solvent was removed under reduced pressure to give the crude product. The crude product was eluted with methylene chloride and eluted with a gradient. After column chromatography (200-300 mesh silica gel), 122 mg of

Molecular Weight:201.7
XLogP3:3
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Exact Mass:200.9473692
Monoisotopic Mass:200.9473692
Topological Polar Surface Area:69.4
Heavy Atom Count:11
Complexity:185
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes