反应详情

4-Chloroaniline (14.3g, .112mol) was dissolved in 30 mL of glacial acetic acid and added slowly to S2Cl2 (75 mL) cooled in a CH2OH--ice bath. The reaction was stirred for 15 hours at room temperature. It was then increased to 50° C. for 4 hours and then to 78° C. for 3 hours. The reaction was cooled and 100 mL of dry benzene added. The mixture was stirred for 30 minutes and filtered. The product was washed two times with 25 mL of benzene. The green/yellow substance was added to 250 mL of crushed ice and 150mL of H2O and stirred 3 hours. The purple product was filtered and added with vigorou stirring to cooled 5% NaOH. The reaction was stirred to one hour, filtered and the pH adjusted to 7 with dilute acetic acid. The product precipitated and was isolated by vacuum filtration to yield 10.7g of 5-chloro-2-aminobenzenethiol (59.8% yield): m.p. 70° -72° C.; NMR(DMSO-d6) δ7.3-6.7(m, 3H); 5.7-4.7(s, 3H); mass spectrum, m/e 159(M calcd. 159.6) 5-Chloro-2-aminobenzenethiol(15g, 0.095mol) was dissolved in 5% NaOH and 17mL of carbon disulfide were added. The reaction was stirred 15 hours at room temperature and heated at reflux for 3 hours. The pH of the reaction was adjusted to 6 with dilute acetic acid and filtered to yield 16.9g of 6-chloro-2-mercaptobenzothiazole (89.4% yield): m.p. 243° -246° C. (decomposes); NMR(DMSO-d6) δ11.5(s, lH); 8.0-7.2(m, 3H)

1. temperatureheated
2. temperatureat reflux for 3 hours
3. filtrationfiltered