L-扁桃酸正丁酯的合成

以L-扁桃酸与正丁醇为原料,在对甲苯磺酸催化下合成了手性拆分剂L-扁桃酸正丁酯,通过正交实验确定优化反应条件为:L-扁桃酸0.1 mol,n(L-扁桃酸):n(正丁醇)=1∶2,对甲苯磺酸0.1 g,甲苯50 mL,回流反应约5 h,酯化率99%,收率在96%以上。其结构经1H NMR确证。

Synthesis of n-Butyl L-Mandelate

A chiral resolving reagent,n-butyl L-mandelate,was synthsized from L-mandelic acid and n-buta-nol by refluxing for 5 h using p-toluene sulfonic acid as catalyst.The effect of molar ratio of reactant,amount of solvent and catalyst on the yield were investigated by orthogonal test.The optimum reaction conditions were as follow: L-mandelic acid was 0.1 mol;the molar ratio of L-mandelic acid to n-buta-nol was 1∶2;the amount of p-toluene sulfonic acid was 0.1 g;and toluene was 50 mL.The yield was over 96% and the esterification rate was about 99% under the optimum reaction conditions.The structure of the product was confirmed by()~1H NMR.