A Membrane-Stabilized Preferential Crystallization Process

结晶为砾岩混合物的手性化合物的外消旋混合物可以使用直接优先结晶技术光学分解。该方法是基于将过饱和溶液中的对映体选择性沉积到为此目的提供的光学纯种子晶体上。该技术在其避免手性助剂和附加的工艺化学方面具有固有的优点，这些是用于生产光学纯药物的其他方法的特征。虽然优先结晶已经成功地应用于几种重要的手性化合物，如果不是因为选择性结晶是一个难以大规模控制的过程这一事实，它无疑会得到更广泛的应用。研究了膜稳定优先结晶分离立体异构体的可行性和潜在效益。在新工艺中，选择性膜被用来限制单个对映体和种子，以提高结晶的稳定性，从而提高工艺的可靠性和效率。

Racemic mixtures of chiral compounds that crystallize as conglomerate mixtures may be optically resolved using the technique of direct preferential crystallization. The method is based on the selective deposition of enantiomers from supersaturated solution onto optically pure seed crystals provided for this purpose. The technique has inherent advantages in its avoidance of the chiral auxiliaries and additional process chemistry that are characteristic of other methods for producing optically pure drugs. While preferential crystallization has been applied successfully to produce several important chiral compounds, it would undoubtedly be more widely used were it not for the fact that selective crystallization can be a difficult process to control on the large scale. It is proposed to examine the feasibility and potential benefits of membrane-stabilized preferential crystallization for stereoisomer separations. In the novel process, selective membranes are used to confine individual enantiomers and seed in such away as to enhance the stability of crystallization and thereby to improve process reliability and efficiency.