申请人:SHELL INTERNATIONALE RESEARCH
MAATSCHAPPIJ B.V.
公开号:EP0426253A1
公开(公告)日:1991-05-08
A process is disclosed for preparing a 2,2-R₁,R₂-1,3-dioxolane-4-carboxylic acid or salt thereof rich in either the R or S enantiomer which process comprises
a) preparing a solution which contains a non-racemic mixture of R and S enantiomer of a carboxylate of the formula
and Mn+ ions,
wherein R₁ and R₂ are each, independently, H or an unsubstituted or substituted alkyl group, or R₁ and R₂, together with the carbon atom to which they are attached, form an unsubstituted or substituted carbocyclic ring, and M is an alkali metal, an alkaline earth metal, a group IIb metal, boron, or an ammonium, di- or tri-alkanolammonium ion having 2 or 3 carbon atoms or a tetra C₁-C₁₆ alkyl ammonium ion, and n is the valency of M;
b) reducing the solubility of the Mn+ salt of compound (I); and
c) separating the resulting crystals from the mother liquor.
本发明公开了一种制备富含 R 或 S 对映体的 2,2-R₁,R₂-1,3-二氧戊环-4-羧酸或其盐的工艺,该工艺包括
a) 制备一种溶液,该溶液包含式中羧酸的 R 和 S 对映体的非外消旋混合物
和 Mn+ 离子、
其中 R₁ 和 R₂ 各自独立地为 H 或未取代或取代的烷基,或 R₁ 和 R₂ 与它们所连接的碳原子一起形成未取代或取代的碳环、M 是碱金属、碱土金属、IIb 族金属、硼,或具有 2 或 3 个碳原子的铵、二烷基或三烷基铵离子或四 C₁-C₁₆ 烷基铵离子,n 是 M 的化合价;
b) 降低化合物 (I) 的 Mn+ 盐的溶解度;以及
c) 从母液中分离得到的晶体。