Реакция #1833240

Уравнение реакции

5-Bromo-3-fluorobenzene-1,2-diol

thiophosgene

Sodium hydroxide

→

title compound

Выход 62.1%

6-Bromo-4-fluorobenzo[d][1,3]dioxole-2-thione

Выход 62.1%

Растворители

chloroform

ethyl acetate

Условия реакции

Обработка

1. 1
   workup.WAITAfter 1 h
2. 2
   Другоеthe chloroform was removed under vacuum
3. 3
   workup.ADDITIONthe pH was adjusted to 2 by addition of 6 M HCl
4. 4
   ДругоеThe solid that was formed
5. 5
   Промывкаwashed with saturated NaCl (30 mL)
6. 6
   Сушкаdried (Na2SO4)
7. 7
   Другоеevaporated
8. 8
   ДругоеThe material was purified by flash chromatography

Методика

5-Bromo-3-fluorobenzene-1,2-diol (2.0 g, 9.7 mmol, prepared according to Lu, Hejun; Tang, Peng Cho; Chen, Yiqian; Wang, Shenglan; Wang, Hua; Zhang, Lei; Li, Jun, WO 2011140936 A1) was dissolved in chloroform (25 mL), treated with thiophosgene (1.2 g, 11 mmol) and cooled to 0-5° C. Sodium hydroxide (10% aqueous, 8.9 g, 22 mmol) was added dropwise with vigorous stirring over 30 min. After 1 h, the chloroform was removed under vacuum and the pH was adjusted to 2 by addition of 6 M HCl. The solid that was formed was taken up in ethyl acetate (120 mL), washed with saturated NaCl (30 mL), dried (Na2SO4) and evaporated. The material was purified by flash chromatography using a 0-30% ethyl acetate-hexane gradient to give the title compound as a tan solid (1.5 g, 62%): mp 41-42° C.; 1H NMR (400 MHz, CDCl3) δ 7.35-7.30 (m, 1H), 7.29 (d, J=1.6 Hz, 1H); 19F NMR (376 MHz, CDCl3) δ −128.93; EIMS m/z 248/250.

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