In the realm of pharmaceutical and fine chemical synthesis, a deep understanding of the properties of key intermediates is essential for optimizing reaction pathways and ensuring product quality. (S)-2-hydroxybutanoic acid, a molecule recognized by its CAS number 3347-90-8, is a prime example. This chiral alpha-hydroxy acid plays a pivotal role, particularly as an intermediate in the synthesis of Idelalisib, a significant therapeutic agent. Examining its chemical properties reveals why it is so valued in complex organic synthesis.

The identity of (S)-2-hydroxybutanoic acid is established by its chemical name, (2S)-2-hydroxybutanoic acid, and its molecular formula, C4H8O3. Its molecular weight is a modest 104.104. Physically, it appears as an off-white to light yellow crystalline powder, a form that typically facilitates handling and weighing in laboratory and industrial settings. The melting point, generally falling within the range of 50-54°C, provides a stable solid form at room temperature, which is advantageous for storage and transportation. Its density of approximately 1.2 g/cm³ is typical for organic compounds of its size and structure.

Crucially for its pharmaceutical applications, (S)-2-hydroxybutanoic acid must meet high purity standards, with assays often required to be ≥98.0%. The presence of the hydroxyl group and the carboxylic acid group makes it a versatile reactant. The hydroxyl group can participate in esterification or etherification reactions, while the carboxylic acid group can undergo esterification, amidation, or salt formation. The chiral center at the alpha-carbon is its most distinguishing feature, enabling stereoselective reactions that are fundamental in producing enantiomerically pure drugs.

The synthesis of Idelalisib serves as a major application where the specific stereochemistry of (S)-2-hydroxybutanoic acid is leveraged. Achieving the correct enantiomeric form of the final drug product relies heavily on the purity of this starting material. When seeking to buy (S)-2-hydroxybutanoic acid, chemists must ensure that the supplier can guarantee the enantiomeric integrity. The development of new synthetic routes for Idelalisib often involves intricate steps that utilize the inherent chirality of (S)-2-hydroxybutanoic acid to control stereochemistry throughout the process. This makes it an indispensable component for any S-2-hydroxybutanoic acid manufacturer aiming to serve the pharmaceutical market.

Understanding these chemical and physical properties allows for more efficient and predictable reaction outcomes. Whether for established processes like Idelalisib synthesis or for novel research endeavors, (S)-2-hydroxybutanoic acid remains a key chiral intermediate. Its reliable availability, along with consistent quality and purity, is a testament to the advancements in chemical manufacturing and supports the continuous innovation in drug discovery and development.