Development of catalytic asymmetric reactions based on a molecular assembly

1.为了使所制备的铵催化剂在胶束中有合理的取向，我们设计合成了四种在辛可尼定中含有烷基和聚醚侧链的铵催化剂。虽然我们已经开发了一种简便的方法来在辛可尼定衍生的季铵盐中引入烷基和多醚基团，但在这些催化剂上进行的亚氨基甘氨酸酯的不对称烷基化反应只产生了相应的产物，其对映体选择性低于原始催化剂。2.我们首次用手性双齿配体(高达98%ee)合成了第一个手性双齿配体催化的二苯亚胺甘氨酸二苯亚胺的烯丙基取代反应(最高可达98%ee)，并通过简单地交换碱的方法成功地合成了这两种非对映异构体。3.由于我们成功地进行了分支产物的对映选择性合成接下来，我们研究了红外催化的不对称合成季胺酸烯丙基烷基化反应。方法B用于磷酸和丙氨酸酯的合成，得到了产率和立体选择性均可接受的手性季铵盐类氨基酸。4.我们发现硫脲能显著促进TMSCN和烯酮硅基缩醛与硝酮和醛的亲核加成反应。此外，含有叔氨基的硫脲作为双官能团有机催化剂具有很好的催化性能，可以促进丙二酸酯与多种对映体选择性较高的硝基烯烃的Michael反应。在没有溶剂的情况下，反应也是成功的。

1.With an aim of proper alignment of the prepared ammonium catalysts in a micelle, we designed and synthesized four ammonium catalysts, which possess alkyl and poly-ether side-chains into the cinchonidine. Although we have developed a convenient method for the introduction of alkyl and poly-ether groups into the cinchonidine-derived quatemary ammonium salts, the asymmetric alkylation of imino glycinate using these catalysts only gave rise to the corresponding products with lower enantioselectivity than that of the original catalyst.2.We have developed the first enantioselective Ir-catalyzed allylic substitutions of diphenylimino glycinate by using chiral bidentate ligand (up to 98% ee), and also succeeded in the diastereoselective asymmetric synthesis of both diastereomers by simply switching the base employed such as KOH (method A) and LiHMDS (method B).3.Since we succeeded in the enantioselective synthesis of the branch products, we next investigated the asymmetric synthesis of quaternary amino acids using the Ir-catalyzed allylic alkylation of various alaninates. The adoption of method B to phosphate and alaninate gave chiral quaternary amino acids with acceptable yield and stereoselectivity.4.We found that thiourea dramatically enhanced the nucleophilic addition of TMSCN and ketene silyl acetals to nitrones and aldehydes. Furthermore, thiourea bearing a tertiary amino group worked well as a bifunctional organocatalyst, and promoted the Michael reaction of malonates to various nitroolefins with high enantioselectivities. The reaction was also successful without solvent.