Key Properties and Synthesis Routes of 2-Bromo-1-(2-hydroxyphenyl)ethanone

In the realm of fine chemicals and organic synthesis, understanding the fundamental properties and efficient synthesis routes of key intermediates is crucial. 2-Bromo-1-(2-hydroxyphenyl)ethanone, identified by its CAS number 2491-36-3, is one such compound that holds significant value due to its specific physical and chemical characteristics, as well as its adaptability in various synthetic methodologies. This article outlines these essential aspects, providing insights for chemists and researchers utilizing this versatile molecule in their work.

Physically, 2-bromo-1-(2-hydroxyphenyl)ethanone is typically described as an off-white to pale yellow crystalline powder. Its melting point is reported in the range of 44-48°C, a characteristic that aids in its identification and purification. Chemically, the molecule possesses a reactive alpha-bromine atom and a hydroxyl group on an aromatic ring, adjacent to an acetyl group. This combination makes it highly susceptible to nucleophilic substitution reactions at the bromine site and allows for further functionalization at the hydroxyl group or the carbonyl center. The presence of the bromine atom, a good leaving group, is key to its utility in building more complex organic structures, making it an excellent choice for organic synthesis and as a precursor in pharmaceutical intermediates synthesis.

The synthesis of 2-bromo-1-(2-hydroxyphenyl)ethanone primarily involves the alpha-bromination of 2'-hydroxyacetophenone. Various methods have been developed to achieve this transformation efficiently and selectively. One common approach utilizes molecular bromine in a suitable solvent like acetic acid. Alternatively, milder brominating agents such as N-bromosuccinimide (NBS) are often employed, sometimes in conjunction with catalysts like acidic alumina (Al₂O₃) to enhance selectivity for the desired alpha-brominated product. Studies have explored different solvent systems, with methanol proving effective for alpha-bromination when using Al₂O₃, yielding up to 89% of the target compound. Careful control over reaction temperature and stoichiometry is vital for maximizing yield and minimizing unwanted side products.

The choice of synthesis route often depends on factors such as desired purity, scale of production, cost-effectiveness, and safety considerations. For example, electrochemical methods using ammonium bromide and catalytic sulfuric acid have emerged as greener alternatives, avoiding the direct handling of hazardous elemental bromine. When sourcing this chemical, whether to buy or purchase for research or industrial applications, it is advisable to work with a reputable manufacturer in China or a specialized supplier. These sources can provide detailed specifications, Certificates of Analysis (CoA), and ensure product consistency, which are critical for reliable organic synthesis outcomes.

In conclusion, the key properties and accessible synthesis routes of 2-bromo-1-(2-hydroxyphenyl)ethanone (CAS 2491-36-3) solidify its position as a valuable intermediate in the chemical industry. Its reactive nature makes it a cornerstone for various organic synthesis processes, particularly in the critical field of pharmaceutical intermediates synthesis. A thorough understanding of its characteristics and synthesis pathways empowers chemists to effectively utilize this compound in developing new materials and medicines.