新型四齿手性硫氮配体的合成及其在不对称催化还原苯乙酮中的应用  

Synthesis and Application of Two Novel Tetradentate Chiral Ligands to Asymmetric Transfer Hydrogen of Acetophenone

作　　者：于会娟[1] 赵营[1] 韩西伦 莫伟杰[1] 余林[1] 

机构地区：[1]广东工业大学轻工化工学院,广东广州510006

出　　处：《合成化学》2015年第5期382-386,共5页Chinese Journal of Synthetic Chemistry

基　　金：国家自然科学基金资助项目(21306026)

摘　　要：以(1S,2S)-(+)-1,2-二苯基乙二胺为原料,分别与2-噻唑甲醛和4-咪唑甲醛经缩合反应合成了两个新型的四齿手性亚胺配体——N,N'-二(2-噻唑)-1,2-二苯基乙二胺(L1)和N,N'-二(4-咪唑)-1,2-二苯基乙二胺(L2),其结构经1H NMR,IR和ESI-MS表征。L1与Ir Cl(cod)2,L2与[Ir HCl2(cod)]2分别经原位反应制得催化剂CatⅠ和CatⅡ。以异丙醇为氢源,研究了CatⅠ和CatⅡ对苯乙酮经不对称氢转移反应合成手性α-苯乙醇的催化性能。结果表明:在最佳反应条件[苯乙酮0.5 mmol,n(KOH)∶n(Cat)=4∶1,异丙醇15 m L,于45℃反应10 h]下,CatⅠ为催化剂时,转化率90%,ee值33%;CatⅡ为催化剂时,转化率87%,ee值27%。Two novel tetradentate chiral ligands,（ 1S,2S）-N,N＇-bis（ 2-thiazole）-1,2-diphenylethylenediimine（ L1） and（ 1S,2S）-N,N＇-bis（ 4-imidazole）-1,2-diphenylethylenediimine（ L2）,were synthesized by condensation of（ 1S,2S）-（ ＋）-1,2-diphenylethylenediamine with 4-imidazole formaldehyde or 2-thiazole formaldehyde,respectively. The chiral catalysts（ CatⅠ and Cat Ⅱ） were prepared by reaction in-suit of L1 with Ir Cl（ cod）2or L2 with [Ir HCl2（ cod） ]2,respectively. The structures were characterized by1 H NMR,IR and ESI-MS. The catalytic activities of the catalysts in asymmetric transfer hydrogenation reaction of acetophenone with i-Pr OH were investigated. Under the optimum reaction conditions[acetophenone was 0. 5 mmol,n（ KOH） ∶ n（ Cat） = 4 ∶ 1,i-Pr OH 15 mL,at 45 ℃ for 10 h],the conversion and ee value were 90% and 33% for Cat Ⅰ,87% and 27%for Cat Ⅱ,respectively.

关 键 词：手性四齿配体 合成 不对称氢转移 催化 苯乙酮 手性芳香仲醇 

分 类 号：O626[理学—有机化学] O643.36[理学—化学]