<i>N</i>-Primary-Amine-Terminal β-Turn Tetrapeptides as Organocatalysts for Highly Enantioselective Aldol Reaction
作者:Feng-Chun Wu、Chao-Shan Da、Zhi-Xue Du、Qi-Peng Guo、Wei-Ping Li、Lei Yi、Ya-Ning Jia、Xiao Ma
DOI:10.1021/jo9005766
日期:2009.7.3
solution. They were first applied to catalyze aldolreactions, and were found to be effective catalysts for the transformations. The tetrapeptide Val-d-Pro-Gly-Leu-OH (1g) was the optimal organocatalyst. It was shown that the intensive β-turn conformation, indicated by CD and NOESY spectra, contributed to the (R)-aldol and high enantioselectivity of the reaction of acetone in MeOH, whereas the sharply varied
设计并合成了四肽,该四肽包含一个终止的伯胺和构象受限的d -Pro-Gly或d -Pro-Aib(2-氨基异丁酸)链段作为强β-转核元素,并通过N-模块二肽与溶液中的C模块二肽。它们首先被用于催化羟醛反应,并被发现是有效的转化催化剂。四肽Val- d -Pro-Gly-Leu-OH(1g)是最佳的有机催化剂。结果表明,在密集的β转角构象,通过CD和NOESY光谱表明,促成了(ř)-丙酮中的丙酮反应具有较高的对映选择性,而急剧变化的构象应有助于1,2-二氯乙烷(DCE)中反应的低对映选择性和(S)产物。羟基丙酮反应中的不对称诱导不受溶剂的影响,在MeCN中添加1克添加剂(S)-BINOL可达到主要的反产物。
Organocatalysis of asymmetric aldol reaction in water: comparison of catalytic properties of (S)-valine and (S)-proline amides
作者:A. S. Kucherenko、D. E. Siyutkin、R. R. Dashkin、S. G. Zlotin
DOI:10.1007/s11172-013-0132-z
日期:2013.4
(S)-Valine amides containing (S)- or (R)-α-phenylethyl substituents at N1 atom efficiently catalyze asymmetric aldol reactions between cyclic (heterocyclic) ketones and aromatic aldehydes in water, predominantly giving rise to the aldol anti-diastereomers in high yields (up to 98%) and enantiomeric excess (up to 94%).
A series of functionalized ionicliquids (FILs) incorporated with chiral-pyrrolidine unit have been synthesized and tested as reusable organocatalysts for direct aldolreactions. FIL 1b in combination with acetic acid and water as additives could effectively catalyze direct aldolreactions of various ketone donors in high yields and the FIL catalyst was easily recycled and reused for six times with
Monofunctional primary amine: A new class of organocatalyst for asymmetric Aldol reaction
作者:KHIANGTE VANLALDINPUIA、PORAG BORA、GHANASHYAM BEZ
DOI:10.1007/s12039-017-1237-y
日期:2017.3
organocatalysts involving a primaryamine as the only functional group is developed for catalytic asymmetric aldol reaction of cyclohexanone/cyclopentanone with various aryl aldehydes in the presence of benzoic acid as an additive at −10∘C. In an unexpected observation, the primaryamine catalyzed reactions gave excellent yield and good to excellent stereoselectivity, while secondary amines were found to have
Core–shell silica magnetic microspheres supported proline as a recyclable organocatalyst for the asymmetric aldol reaction
作者:Honglei Yang、Shuwen Li、Xiaoyu Wang、Fengwei Zhang、Xing Zhong、Zhengping Dong、Jiantai Ma
DOI:10.1016/j.molcata.2012.07.017
日期:2012.11
enantioselectivity (up to 80%) in the asymmetric aldolreaction between aldehyde acceptors and ketone donors. On the other hand, the synthesized catalyst could be rapidly separated from the reaction mixture through an external magnetic field and reused up to five runs without any obvious loss of activity, indicating its easy-separated property and excellent recyclability.