Molecular Formula | C6H3BrF2O |
Molar Mass | 208.99 |
Density | 1.858±0.06 g/cm3(Predicted) |
Melting Point | 223°C (dec.)(lit.) |
Boling Point | 65-66°C/0.1mm |
Flash Point | 82.1°C |
Vapor Presure | 0.121mmHg at 25°C |
BRN | 8831044 |
pKa | 6.75±0.15(Predicted) |
Storage Condition | Inert atmosphere,Room Temperature |
Refractive Index | 1.538 |
Physical and Chemical Properties | Colorless transparent liquid |
Risk Codes | R63 - Possible risk of harm to the unborn child R36/37/38 - Irritating to eyes, respiratory system and skin. |
Safety Description | S36/37 - Wear suitable protective clothing and gloves. S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. |
WGK Germany | 3 |
RTECS | GM8960000 |
Hazard Note | Toxic |
Hazard Class | IRRITANT |
Use | 5-bromo-2, 3-difluorophenol is an important intermediate for the synthesis of a large number of compounds with physiological or pharmacological activity, the compounds can also be used in the synthesis of agrochemicals and liquid crystal compounds, and are increasingly used. |
preparation | (1) to a ML four-port reaction bottle equipped with a magnet and a return condenser, add 84.4g-3, 5-trifluorobromobenzene (0.4mol), 1.2 mL methanol and 67.2g KOH (mol). After the addition, the temperature was raised to 60 ℃, and the reaction was stirred for 6H, until the raw materials are basically reacted. After the reaction, the reaction solution was frozen at -10 °c for 5h, and a large number of crystals were precipitated. The crystals were separated by Suction filtration to obtain 80.0g, the content of 3-difluoro-5-bromoanisole was 99.2%. Methanol recovery can be reused. (2) add 80.0G 2, 3-difluoro-5-bromoanisole (0.36mol) obtained above to a ML reaction flask equipped with a magnet and a reflux condenser, ML of toluene and 71.8G of AlCl3 (0.54mol). Under the protection of nitrogen, the temperature was raised to 80 ° C., the reaction was stirred for 5h, and the reaction progress was followed by gas chromatography until the basic reaction of 2, 3-difluoro-5-bromoanisole was completed. After completion of the reaction, the reaction solution was washed with water, the upper layer was separated, the toluene was removed by rotary evaporation, and distilled under reduced pressure to obtain 67.7g of 5-bromo-2, 3-difluorophenol, The product content was 99.3% by GC analysis. The recovered toluene can be reused after drying treatment. After detection, the NMR spectrum and mass spectrum of the obtained target product were consistent with the standard sample, and the total yield of the two-step reaction was 81.0%. |
Chemical properties | colorless transparent liquid |