(S)-(+)-2-氨基丙醇合成工艺改进

对硼氢化钾还原法制取(S) (+) 2 氨基丙醇(AP)工艺进行了改进,采用氯化四甲基铵与硼氢化钾反应制备硼氢化四甲基铵来提高硼氢离子的还原性,还原L 2 氨基丙酸乙酯盐酸盐制取AP。比较了不同链长的硼氢化季铵盐对还原反应的影响,筛选出最优还原剂硼氢化四甲基铵。考察了物质的量比对反应的影响,获得了最优工艺条件:n(硼氢化四甲基铵)∶n(L 2 氨基丙酸乙酯盐酸盐)=(1 52～1 55)∶1,45℃反应3～4h,AP收率89%。w(C3H9NO)=98 6%(高氯酸滴定法测定)。同原工艺直接使用硼氢化钾还原剂比较,生产1tAP少用硼氢化钾1 1～1 2t。

An Improved Preparation Process for (S)-(+)-2-Amino-1-propanol

The preparation process for ( S )-(+)-2-amino-1-propanol(AP) by reduction with potassium borohydride(PB) was improved.AP was prepared by reduction of ethyl L -2-aminopropionate hydrochloride(EAPH) with tetramethylammonium borohydride(TAB),a highly reactive reductant,which was synthesized from tetramethylammonium chloride and PB.The effect of carbon chain length of ammonium borohydride on the reduction was investigated,indicating that TAB has the highest reduction output.The optimum process conditions were found.Thus,reacting at 45 ℃ for 3～4 h with n (TAB)∶ n (EAPH)=(1.52～1.55)∶1,total yield of AP was 89%(by weight) and w (C_3H_9NO)=98.6% (pherchloric acid titration method).Compared with the original process in which PB was used directly,the consumption of PB in the present process was 1.1～1.2 ton less for each ton of AP produced.