Research on Asymmetric Reaction with New Chiral Schiff Base-Metal Cpmplexes

我已经发明了许多新的用手性希夫碱金属配合物作为催化剂的催化对映选择反应。其中之一是对映选择性地将三甲基氰加成到醛类化合物上，得到90%以上的高旋光性氰醇。本项目研究了一些手性席夫碱的对映选择性催化反应。第一个是二烯酮对映选择性加成到醛上得到手性5-羟基-3-酮酯。部分产品可用于合成降低血液中胆固醇的新药。使用10 mo1%的手性钛催化剂可获得90%以上的ee产品的定量化学产率。二是对称环氧化合物如环氧环己烯的对映选择性开环芳化反应。反应介质中手性席夫碱的烷氧锂作为催化剂，可得到ee大于90%的开环产物。产物很容易再结晶，得到光学纯的化合物。此外，反式2-芳基环己醇是制备各种药物的非常有用的手性前体。这项发明被申请为专利。

I already invented many new catalytic enantioselective reactions using chiral schiff base-metal complexes as catalyst. One of them was enantioselective addition of trimethylcyanide to aldehydes to give highly optically active cyanohydrins over 90% ee.The investigations by this project were new some enantioselective catalysis using chiral schiff bases. The first was the enantioselective addition of diketene to aldehydes to give chiral 5-hydroxy-3-ketoesters. Some kind of the products can be applied for the synthesis of new medicine lowering colesteroles in blood. The use of 10 mo1% of chiral titanium catalyst afforded over 90% ee's product in quantitative chemical yield.The second research was the enantioselective ring opening arylation of symmetrical epoxides such as cyclohexene oxide. Lithium alokoxide of chiral schiff bases in reaction media acts as catalyst to give ring opening product having over 90% ee. The products easily were recrystallized to give optically pure compounds. Also trans-2-arylcyclohexanols are very useful chiral precursors to prepare a variety of medicines. This invension was applied as a patent.