Catalytic Asymmetric Strecker Synthesis. Preparation of Enantiomerically Pure α-Amino Acid Derivatives from Aldimines and Tributyltin Cyanide or Achiral Aldehydes, Amines, and Hydrogen Cyanide Using a Chiral Zirconium Catalyst
Strecker amino acid synthesis starting from achiral aldehydes, amines, and HCN using a chiral zirconium catalyst has also been achieved. The three-component asymmetric process reported here significantly improves upon the original Strecker reaction, and has advantages over previous reactions using unstable imines (Schiffbases) as starting materials. Moreover, high yields and enantioselectivities have
Strecker reactions of aldimines with Bu3 SnCN in the presence of the novelchiralzirconium binuclear catalyst 1 provide α-aminonitriles in good yields and with high enantioselectivities. The reaction can be applied to a wide range of substrates. Since both enantiomers of the chiral sources are readily avaibable, both enantiomers of the α-aminonitriles are easily prepared according to this method.
Montmorillonite-Silica-Graphene oxide composite incorporating with chiral thiourea for the Strecker reaction
作者:Pratikkumar Lakhani、Chetan K. Modi
DOI:10.1016/j.mcat.2024.114080
日期:2024.4
as-prepared composite demonstrates improved thermal stability compared to neat MMT and GO. It was followed by incorporating chiral thiourea (CTU) scaffold into MMT-silica-GO-based composite to establish chiral MMT-silica-GO-CTU-based heterogeneous system and tested over Strecker reaction, revealing high activity and selectivity. FTIR, Raman spectroscopy, powder X-ray diffraction, SAXS, XPS, BET, SEM, EDAX, and
本研究成功地将氧化石墨烯(GO)纳米片和二氧化硅嵌入蒙脱石(MMT)夹层中,并将其沉积在其外表面,制成蒙脱石、二氧化硅和氧化石墨烯复合材料(MMT-二氧化硅-GO)。与纯 MMT 和 GO 相比,所制备的复合材料表现出更高的热稳定性。随后将手性硫脲(CTU)支架加入到基于MMT-二氧化硅-GO的复合材料中,建立基于手性MMT-二氧化硅-GO-CTU的异质体系,并通过Strecker反应进行测试,显示出高活性和选择性。使用 FTIR、拉曼光谱、粉末 X 射线衍射、SAXS、XPS、BET、SEM、EDAX 和热重分析来表征样品。这被认为是复合材料组分之间的协同效应,增强了活性位点的接触和催化剂的分散。总体而言,基于手性 MMT-silica-GO-CTU 的异质系统似乎是 Strecker 反应的有希望的候选者。