The present process produces the meso dialkyl 2,5-dihaloadipate from a mixture of the racemic dialkyl 2,5-dihaloadipate and meso 2,5-dihaloadipate. In the disclosed process, a 2,5-dihaloadipoyl halide is formed under conditions which result in the formation of an acidic compound. The 2,5-dihaloadipoyl halide is then esterified under conditions wherein the ester of the dihaloadipoyl halide is allowed to remain in contact with the acidic compound, thus allowing the racemic diester to epimerize in the presence of the acidic compound to the meso form and then the meso diester spontaneously crystallizes. In the last stage, the meso diester produced is removed.
本工艺从外消旋二烷基 2,5-二卤代
己二酸酯和中生二烷基 2,5-二卤代
己二酸酯的混合物中生产中生二烷基 2,5-二卤代
己二酸酯。在所公开的工艺中,2,5-二卤代二偶
酰卤是在形成酸性化合物的条件下形成的。然后,在允许二卤代二甲
酰卤的酯与酸性化合物保持接触的条件下对 2,5-二卤代二甲
酰卤进行酯化,从而使外消旋二酯在酸性化合物的存在下外延成中间形式,然后中间二酯自发结晶。在最后一个阶段,生成的中间二酯被移除。