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

不对称合成是当前的研究热点。因此，我们通过酶促和非酶促技术研究了以下不对称反应.有机溶剂中脂肪酶催化环酸酐不对称开环反应。脂肪酶（amano P）催化3-取代谷氨酸酐与正丁醇的不对称开环反应，得到ee值为60 - 91%的半酯，同时，该脂肪酶不可逆地催化2-取代酸酐优先在低位阻羰基开环，得到高区域选择性的单酯.有机溶剂中脂肪酶催化2-羟基-1-芳基乙醇和氢过氧化物的不可逆高对映选择性拆分。在有机溶剂中脂肪酶是醇与烯醇酯不可逆酯交换反应的优良催化剂。利用该酶反应，成功地实现了外消旋卤代醇和氢氧化物的立体选择性酰化反应.脂肪酶催化联萘酚的立体选择性酰化及其酯的脱酰化。研究发现假单胞菌脂肪酶催化联萘酚与烯醇酯的酰化反应及其外消旋单酯的脱酰或醇解反应。从反应的两个侧面看，均以较高的光学产率得到了单酯和联萘酚.光学活性内酯的不对称合成新方法。在环结构中含有萘二胺或均二苯乙烯二胺作为C_2-手性助剂的环二酰胺在高d.e.下与三氟乙酸有效地转化为内酯。

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.