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

Temperature

2.5 °C

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.

1. waitAfter 1 h
2. customthe chloroform was removed under vacuum
3. additionthe pH was adjusted to 2 by addition of 6 M HCl
4. customThe solid that was formed
5. washwashed with saturated NaCl (30 mL)
6. dry with materialdried (Na2SO4)
7. customevaporated
8. customThe material was purified by flash chromatography

ORD record

ord-97601adef8dd4a8bb2c5f40a228bfc7c

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09149038B2