1040924-08-0Relevant articles and documents
New chiral thiols and C2-symmetrical disulfides of Cinchona alkaloids: ligands for the asymmetric Henry reaction catalyzed by CuII complexes
Zielinska-Blajet, Mariola,Skarzewski, Jacek
, p. 1992 - 1998 (2009)
Seven Cinchona alkaloids were reacted with thioacetic acid and Bu3P/diethyl diazadicarboxylate in THF at 0-25 °C to give the corresponding thiolacetates with complete inversion of configuration at the substitution center. The thus obtained chir
Synthesis of C 1-symmetric chiral secondary diamines and their applications in the asymmetric copper(II)-catalyzed Henry (Nitroaldol) reactions
Zhou, Yirong,Dong, Junfang,Zhang, Fanglin,Gong, Yuefa
experimental part, p. 588 - 600 (2011/03/20)
A small library of C1-symmetric chiral diamines (L1-L9) was constructed via condensing exo-(-)-bornylamine or (+)-(1S,2S,5R)-menthylamine with various Cbz-protected amino acids. Among them, ligand L1/CuCl 2?2H2O complex (2.5 mol %) shows outstanding catalytic efficiency for Henry reaction between a variety of aldehydes and nitroalkanes to afford the expected products in high yields (up to 98%) with excellent enantioselectivities (up to 99%) and moderate to good diastereoselectivities (up to 90:10). This process is air-and moisture tolerant and has been applied to the synthesis of (S)-2-amino-1-(3,4-dimethoxyphenyl) ethanol (9), a key intermediate for (S)-epinephrine and (S)-norepinephrine. On the basis of HRMS and X-ray diffraction analysis of the L1/CuCl2 complex, a transition-state model was proposed to explain the origin of asymmetric induction. The low catalyst loading, excellent yields and enantioselectivities, inexpensive copper salt, and mild reaction conditions make our catalytic system to be practically useful.
Asymmetric nitroaldol reaction catalyzed by copper-diamine complexes: selective construction of two contiguous stereogenic centers
Kowalczyk, Rafal,Skarzewski, Jacek
experimental part, p. 2467 - 2473 (2010/03/25)
Chiral copper(II) complexes of secondary bisamines derived from 1,2-diaminocyclohexane were successfully used in the diastereoselective nitroaldol reaction. The reactions were carried out in the presence of 10 mol % of the Cu(II) complex and 7.7 mol % of
New highly asymmetric henry reaction catalyzed by CuII and a C1-symmetric aminopyridine ligand, and its application to the synthesis of miconazole
Blay, Gonzalo,Domingo, Luis R.,Hernandez-Olmos, Victor,Pedro, Jose R.
supporting information; experimental part, p. 4725 - 4730 (2009/05/07)
A new catalytic asymmetric Henry reaction has been developed that uses a C1 -symmetric chiral aminopyridine ligand derived from camphor and picolylamine. A variety of aromatic, heteroaromatic, aliphatic, and unsaturated aldehydes react with nit
