Synthesis of novel C2-symmetric chiral crown ethers and investigation of their enantiomeric recognition properties
作者:Yilmaz Turgut、Tarik Aral、Halil Hosgoren
DOI:10.1016/j.tetasy.2009.09.010
日期:2009.10
A series of new C2-symmetric chiralazacrownether macrocycles 1–4 have been synthesized from (S)-3-aryloxy-1,2-propanediol and (S)-1,2-propanediol for the enantiomeric recognition of amino acid ester derivatives. These new macrocycles have been shown to be strong complexing agents for primary organic ammonium salts (with K up to 176.93 M−1 and ΔG° up to 12.81 kJ mol−1) by 1H NMR titration. These
一系列新的c ^ 2 -对称的手性氮杂冠醚大环化合物1 - 4已经从(合成小号)-3-芳氧基-1,2-丙二醇和(小号)-1,2-丙二醇为对映异构体识别氨基酸的酯衍生物。通过1 H NMR滴定显示,这些新的大环化合物是伯有机铵盐(K最高为176.93 M -1和ΔG °最高为12.81 kJ mol -1)的强络合剂。这些大环主体对苯丙氨酸甲酯盐酸盐的D-对映异构体具有K D /的对映选择性键。在具有0.25%CD 3 OD的CDCl 3中,K L高达6.87 。
A new efficient bis(phosphinite)-ruthenium(II) catalyst system for the asymmetric transfer hydrogenation of aromatic ketones
Many chiral ligands bearing phosphorus donor atoms were developed and applied in the area of metal catalyzed asymmetric catalysis. A new chiralbis(phoshinite) ligand was successfully synthesized from optically active (1S,8S)-3,6-[N-(S)-α-phenylethyl]diaza-1,8-diphenoxymethyl-1,8-octanediol in high yield. A ruthenium(II) complex generated in situ from [Ru(η6-p-cymene)(μ-Cl)Cl]2, bis(phosphinite) ligand
A series of β-amino alcohols derivatives were synthesized from (R)-2-amino-1-butanol and (S)-1,2-propanediol, and they have been used as organocatalaysts in the racemic ring opening of epoxide in good yields with high enantiomeric excess (up to 97%).