Studies on the development of enzymatic and non-enzymatic asymmetric synthesis

不对称合成目前引起了相当大的兴趣。因此，我们用酶和非酶技术研究了以下不对称反应。有机溶剂中脂肪酶作用下环酸酐的不对称开环。脂肪酶（amano P）催化3-取代谷氨酸酐与1-丁醇的不对称开环反应，得到ee为60 ~ 91%的半酯。而且，同样的脂肪酶不可逆地催化2-取代酸酐优先在阻碍较少的羰基上开环，得到具有高区域选择性的单酯。脂肪酶催化有机溶剂中2-全-1-芳基乙醇和水过氧化物的不可逆和高度对映选择性分解。脂肪酶是有机溶剂中醇与烯醇酯不可逆酯交换反应的优良催化剂。通过该酶反应，成功地实现了外消旋卤氢和过氧化氢的立体选择性酰化。用脂肪酶进行双酚的立体选择性酰化及其酯的去酰化。研究发现，假单胞菌的脂肪酶能催化双酚与烯醇酯的酰化反应和双酚外消旋单酯的去酰化或醇化反应。从反应的两侧，分别获得了高收率的单酯和双酚。新型不对称合成光活性内酯。以萘二胺或二苯二胺为c_2手性助剂的环二胺在高e下与三氟乙酸有效转化为内酯。

Asymmetric synthesis is of considerable current interest. Thus we investigated the following asymmetric reactions by enzymatic and non-enzymatic techniques.1. Asymmetric ring opening of cyclic acid anhydrides with lipase in organic slovents. A lipase (amano P) catalyzed the asymmetric ring opening of 3-substituted glutamic anhydride with 1- butanol to afford the half esters having 60 - 91 % ee. And also, the same lipase irreversibly catalyzed a ring opening of 2-substituted anhydrides preferentially at the less hindered carbonyl to give monoesters with high regioselectivity.2. Irreversible and highly enantioselective resolution of 2-holo-1-aryl-ethanols and fydroperoxides in organic solvents catalyzed by a lipase. Lipase was found to be an excellent catalyst for irreversible transesterification of alcohols with enol esters in organic solvent. By this enzyme reaction, stereoselective acylation of racemic halohydrines and hydropcroxide was successfully achieved.3. Stereoselective acylation of binaphtol and deacylation of its esters using a lipase. It was found that a lipase from pseudomanas sp. catalyzed a acylation of binaphtol with enol esters and deacylation or alcoholysis of its racemic monoesters. From both side of reaction, the monoesters and binaphtol were obtained in high optical yield respectively.4. Novel asymmetric synthesis of optically active lactones. The cyclic diamides containing naphthyl diamine or stilbendiamine as a C_2-chiral auxiliary in the ring structure were effectively converted to the lactones with trifluoro acetic acid in high d.e.