Bupropion 2-BroMo IMpurity
2-Bromo-3'-chloropropiophenone
CAS: 34911-51-8
Molecular Formula: C9H8BrClO
Bupropion 2-BroMo IMpurity - Names and Identifiers
| Name | 2-Bromo-3'-chloropropiophenone |
| Synonyms | Bupropion 2-BroMo IMpurity α-BroMo-3-chloropropiophenone 2-Bromo-3'-chloropropiophenone 3'-CHLORO-2-BROMOPROPIOPHENONE 2-BROMO-3'-CHLOROPROPIOPHENONE 3'-Chloro-α-bromopropiophenone 2-BROMO-1-(3-CHLOROPHENYL)PROPAN-1-ONE 2-BROMO-1-(3-CHLOROPHENYL)-1-PROPANONE 1-Propanone,2-broMo-1-(3-chlorophenyl)- |
| CAS | 34911-51-8 |
| EINECS | 252-282-1 |
Bupropion 2-BroMo IMpurity - Physico-chemical Properties
| Molecular Formula | C9H8BrClO |
| Molar Mass | 247.52 |
| Density | 1.532 |
| Boling Point | 148-148.5 °C(Press: 9 Torr) |
| Solubility | Soluble in acetonitrile, chloroform, dichloromethane and ethyl acetate. |
| Appearance | Liquid |
| Color | Colorless to pale yellow |
| Storage Condition | Refrigerator, Under Inert Atmosphere |
| Refractive Index | 1.5770 |
Bupropion 2-BroMo IMpurity - Risk and Safety
| HS Code | 2914790000 |
| Hazard Class | IRRITANT |
Bupropion 2-BroMo IMpurity - Reference Information
| Overview | rimonabant is a new weight loss drug, 2-bromo-3 '-chlorophenylacetone is a key intermediate in the synthesis of rimonabant, at present, there are few reports on the synthesis of this intermediate in foreign countries, but there is no report in China. 2-bromo-3 '-chlorophenylacetone has been synthesized by using glacial acetic acid as solvent and p-chlorophenylacetone reacted with liquid bromine at room temperature. The purity of the product is low, it contains a large amount of hard-to-separate by-products. |
| preparation | a reactor equipped with a reflux condenser and a dropping funnel is charged with 48.0g(2.0mol) of magnesium powder, 218.0 ml of tetrahydrofuran (THF) solution was added slowly 2.0g (mol) of bromoethane from the dropping funnel, and the temperature of the reaction solution was controlled to 50-60 ℃ to keep the solution in a slightly boiling state, after completion of dropwise addition, heat reflux was applied for 1.0-1.5h to ensure complete reaction of magnesium and obtain Grignard reagent. Under stirring, M-chlorobenzonitrile 275.2g(2.0mol) was slowly added dropwise to the Grignard reagent prepared above. After the dropwise addition, the reaction was carried out for 3.0-4.0h to form an intermediate, without separation, 3mol/L hydrochloric acid was slowly added dropwise to hydrolyze the intermediate, and the inorganic phase was separated. The organic phase was often subjected to pressure distillation to remove THF, followed by vacuum distillation to obtain 3-chlorophenylacetone. In a four-port reaction flask equipped with an electric stirrer, a reflux condenser and a thermometer, Add 33.7g of 3-chlorophenylacetone, 16.8g of liquid bromine, 50.0G of solvent and 0.75g of catalyst successively, install reflux condenser and thermometer, and start the stirrer. When the temperature is controlled at 15 ℃, start timing, the reaction time was 2.5h. After the end of the reaction, the solvent is distilled off, the remaining solution is washed with water, dissolved by adding refined solvent, then cooled, crystallized, and filtered to obtain refined 2-bromo-3 '-chlorophenylacetone product, the yield of 2-bromo-3'-chlorophenylacetone was 97.13% and the melting point was 76-77 °c. |
Last Update：2024-04-09 02:00:09
