本篇研究目的為利用拆分技術將未使用的藥物「外消旋布洛芬(R,S)-(±)-ibuprofen」回收分離得到價值更高的「右旋布洛芬[(S)-(+)-Ibuprofen]」，應用綠色化學方法作為循環經濟的一部分；拆分技術已應用於非鏡像異構鹽類的分離，如：甲基苄胺[(S)-(-)-α-methylbenzylamine]作為拆分溶劑。在本研究中，透過兩個步驟以達成拆分，首先，將回收的外消旋布洛芬與甲基苄胺的反應，形成右旋布洛芬-甲基苄胺鹽類[(S)-(+)-Ibuprofen-(S)-(-)-α-methylbenzylamine salt]及左旋布洛芬-甲基苄胺鹽類[(R)-(-)-Ibuprofen-(S)-(-)-α-methylbenzylamine salt]，其中，右旋布洛芬-甲基苄胺鹽類則會沉澱析出；第二步，利用添加硫酸與析出的右旋布洛芬-甲基苄胺鹽類反應而得到右旋布洛芬。根據HPLC的純度含量分析得知，回收得到的右旋布洛芬產率為67%，對映體純度為93.2%；右旋布洛芬-甲基苄胺鹽類及右旋布洛芬兩個分子結構成功透過傅里葉轉換紅外光譜(FTIR)、核磁共振氫譜(1H NMR)、光學顯微鏡(OM)及差示掃描量熱法(DSC)分析鑑定；此外，右旋布洛芬的晶體學數據亦透過粉末X-射線繞射(PXRD)分析鑑定。最後，比較本方法與不對稱合成方法(Asymmetric synthesis)，本方法則有較高的產率、較少的步驟、較有利的操作條件及使用較少化學品等的優點。;The aim of this study is to increase the value of recycled (R,S)-(±)-ibuprofen from the unused commercial tablets by resolution, to produce higher valued (S)-(+)-ibuprofen as a part of a circular economy project by applying green chemistry method. The resolution was done by the diastereomeric salt separation method using (S)-(-)-α-methylbenzylamine as a resolving agent. In this work, two steps were performed: (1) reaction of recycled (R,S)-(±)-ibuprofen with (S)-(-)-α-methylbenzylamine to form (S)-(+)-ibuprofen-(S)-(-)-α-methylbenzylamine salt and (R)-(-)-ibuprofen-(S)-(-)-α-methylbenzylamine salt, in which (S)-(+)-ibuprofen-(S)-(-)-α-methylbenzylamine salt was selectively precipitated, followed by (2) recovery of (S)-(+)-ibuprofen by introducing H2SO4 to (S)-(+)-ibuprofen-(S)-(-)-α-methylbenzylamine salt. (S)-(+)-ibuprofen was obtained with 67% overall yield and 93.2% enantiopurity based on HPLC assay. The structures of both (S)-(+)-ibuprofen-(S)-(-)-α-methylbenzylamine salt and (S)-(+)-ibuprofen were successfully verified using FTIR, 1H NMR, OM, and DSC. In addition, the crystallographic data of (S)-(+)-ibuprofen was successfully verified using PXRD. And lastly, by comparing this method with asymmetric synthesis, this method gave better yield, a fewer number of steps, more favorable operating conditions, and fewer chemicals involved.
