Self-assembled organic–inorganic hybrid silica with ionic liquid framework: a novel support for the catalytic enantioselective Strecker reaction of imines using Yb(OTf)3–pybox catalyst
作者:Babak Karimi、Aziz Maleki、Dawood Elhamifar、James H. Clark、Andrew J. Hunt
DOI:10.1039/c0cc01426e
日期:——
Yb(OTf)3âpybox is immobilized in a novel self-assembled ionic liquid hybrid silica and has been successfully applied as a catalyst for the asymmetric Strecker hydrocyanation of aldimines. This catalytic system can be reused for at least 6 times without any significant loss of activity and enantioselectivity.
Catalytic asymmetric Strecker hydrocyanation of imines using Yb(OTf)3–pybox catalysts
作者:Babak Karimi、Aziz Maleki
DOI:10.1039/b908854g
日期:——
We have explored the highly enantioselective Strecker hydrocyanation of a wide range of aromatic, α,β-unsaturated, heterocyclic, and aliphatic aldimines with good to excellent conversions and ees up to 98% in the presence of catalytic amounts of Yb(OTf)3âpybox complexes.
<i>C</i><sub>2</sub>-Symmetric Recyclable Organocatalyst for Enantioselective Strecker Reaction for the Synthesis of α-Amino Acid and Chiral Diamine- an Intermediate for APN Inhibitor
作者:S. Saravanan、Arghya Sadhukhan、Noor-ul H. Khan、Rukhsana I. Kureshy、Sayed H. R. Abdi、Hari C. Bajaj
DOI:10.1021/jo300349f
日期:2012.5.4
Recyclable chiral amide-based organocatalyst 5 efficiently catalyzed asymmetric Streckerreaction of various aromatic and aliphatic N-benzhydrylimines with ethyl cyanoformate as cyanide source at −10 °C to give a high yield (95%) of α-aminonitriles with excellent chiral induction (ee, up to 99%) with the added advantage of recyclability. Based on experimental observations a probable mechanism was proposed
Described herein are compounds of formula (I), related compositions, and their use, for example in the formation of α-amino acids or a precursor thereof such as an α-aminonitrile.
Scaleable catalytic asymmetric Strecker syntheses of unnatural α-amino acids
作者:Stephan J. Zuend、Matthew P. Coughlin、Mathieu P. Lalonde、Eric N. Jacobsen
DOI:10.1038/nature08484
日期:2009.10
but it is still a challenge to obtain non-natural amino acids. Alkene hydrogenation is broadly useful for the enantioselective catalytic synthesis of many classes of amino acids, but it is not possible to obtain α-amino acids bearing aryl or quaternary alkyl α-substituents using this method. The Strecker synthesis—the reaction of an imine or imine equivalent with hydrogen cyanide, followed by nitrile