ChemicalBook CAS DataBase List 3-BROMO-5-NITROBENZOTRIFLUORIDE

3-BROMO-5-NITROBENZOTRIFLUORIDE synthesis

5synthesis methods

Product Name:3-BROMO-5-NITROBENZOTRIFLUORIDE
CAS Number:630125-49-4
Molecular formula:C7H3BrF3NO2
Molecular Weight:270

98-46-4
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$19.00/5g

630125-49-4
243 suppliers
$14.00/1g

Yield:630125-49-4 89.6%

Reaction Conditions:

Stage #1: 3-trifluoromethylnitrobenzenewith sulfuric acid in dichloromethane;water at 35; for 0.166667 h;
Stage #2: with 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione in dichloromethane;water at 35; for 24 h;
Stage #3: with sodium hydroxide in dichloromethane;water at 0 - 35; for 0.333333 h;

Steps:

14

Example 14 1-Bromo-3-nitro-5-trifluoromethyl-benzene (Xl)To a solution of 1-nitro-3-trifluoromethyl-benzene (41.1 mL, 300 mmol, 97%, purchased from Aldrich) in dichloromethane (240 mL) is added 98% sulfuric acid (45.7 mL, 840 mmol) over 10 minutes. The vigorously stirred resulting biphasic mixture is warmed to 35°C and 1 ,3-dibromo-5,5-dimethyl-imidazolidine-2,4-dione (53.1 g in total, 180 mmol) is added in six equal portions over five hours. The mixture is stirred at 35°C for additional19 hours. Thereafter, more than 97% of the starting material is converted according to HPLC analysis. The reaction mixture is allowed to cool to room temperature and added over20 minutes to a stirred 2 M aqueous NaOH solution (210 mL) of 0-5°C while cooling with an ice-water bath. The internal temperature rises temporarily to about 35°C. The two layers are separated. The aqueous layer is extracted with hexane (3 x 200 mL). The combined organic layers are washed with water (200 mL), 5% aqueous sodium metabisulfite solution (2 x EPO 200 ml_), 8% aqueous NaHCO₃ solution (200 ml_) and 10% aqueous NaCI solution (200 mL) and, thereafter, the solvents are evaporated at reduced pressure and 45°C. The obtained liquid is distilled at 0.71 mbar and a bath temperature of 70-80⁰C to give 1-bromo-3-nitro-5- trifluoromethyl-benzene as a pale yellow liquid. Yield: 89.6% (¹H-NMR purity: about 95%). ¹H-NMR (400 MHz, CDCI₃): 8.11 ppm (m, 1 H), 8.45 ppm (m, 1 H), 8.58-8.59 ppm (m, 1 H). Boiling point: approximately 68 ⁰C at 0.71 mbar.

References:

WO2006/135640,2006,A2 Location in patent:Page/Page column 25-26