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适当排列，我们设计并合成了四种具有烷基和聚醚侧链的铵催化剂。虽然我们已经开发了一种将烷基和聚醚基团引入辛可尼定衍生的季铵盐中的方便方法，2.首次利用手性双齿配体实现了Ir催化的二苯基甘氨酸亚胺的不对称烷基化反应（高达98%ee），并且通过简单地切换所使用的碱如KOH（方法A）和LiHMDS（方法B）也成功地非对映选择性地合成了两种非对映异构体。3.由于我们成功地对映选择性地合成了分支产物，我们接下来研究了使用Ir催化的各种丙氨酸的烯丙基烷基化的季氨基酸的不对称合成。采用方法B对磷酸盐和丙氨酸盐进行了手性季胺酸的合成，得到了较好的产率和立体选择性。4.我们发现硫脲显著增强了TMSCN和烯酮甲硅缩醛对硝酮和醛的亲核加成反应。此外，带有叔氨基的硫脲作为一种双功能有机催化剂，可以很好地促进丙二酸酯的Michael反应，并具有高的对映选择性。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.