Indium-Bipyridine Catalyzed, Enantioselective Aminolysis of <i>meso</i>-Epoxides
作者:Christoph Schneider、Enzo Mai
DOI:10.1055/s-2007-984902
日期:——
The scandium-bipyridine-catalyzedenantioselective addition of anilines and O-alkyl hydroxylamines to meso-epoxides has been optimized and extended to a broad range of epoxides and amines. Whereas aromatic meso-epoxides generally furnished the corresponding 1,2-amino alcohols in excellent enantioselectivities, aliphatic meso-epoxides only gave rise to moderate enantioselectivities in the aminolysis
The catalytic asymmetric ring opening of meso-epoxides with aromatic amines was achieved using a new proline-basedN,N′-dioxide-indiumtris(triflate) complex in high yields (up to 99%) with excellent enantioselectivities (up to 99% ee) under mild conditions. The coordination ability of N,N′-dioxide 1c was investigated by X-ray and NMR analysis. A plausible seven-coordinate transition state model was
The scandium-bipyridine-catalyzedenantioselective addition of anilines and O-alkyl hydroxylamines to meso-epoxides has been optimized and extended to a broad range of epoxides and amines. Whereas aromatic meso-epoxides generally furnished the corresponding 1,2-amino alcohols in excellent enantioselectivities, aliphatic meso-epoxides only gave rise to moderate enantioselectivities in the aminolysis
Enantioselective desymmetrization of meso-epoxides with anilines catalyzed by polymeric and monomeric Ti(IV) salen complexes
作者:Rukhsana I. Kureshy、Manish Kumar、Santosh Agrawal、Noor-Ul H. Khan、Balchand Dangi、Sayed H. R. Abdi、Hari C. Bajaj
DOI:10.1002/chir.20868
日期:2011.1
The active catalysts for the enantioselective ring opening (ARO) of meso‐stilbene oxide, cis‐butene oxide, cyclohexeneoxide, cyclopentene oxide, and cyclooctene oxide with various substituted anilines were generated in situ by the reaction of Ti(OiPr)4 with poly‐[(R,R)‐N,N′‐bis‐3‐(1,1‐dimethylethyl)‐5‐methylene salicylidene} cyclohexane‐1,2‐diamine]‐1 and (1R,2R)‐N,N′‐bis[3,5‐di(tert‐butyl)salicylidene]
Facile Enantioselective Ring-Opening Reaction ofmeso Epoxides with Anilines Using (S)-(–)-BINOL-Ti Complex as a Catalyst
作者:Rukhsana I. Kureshy、Surendra Singh、Noor-ul H. Khan、Sayed H. R. Abdi、Eringathodi Suresh、Raksh V. Jasra
DOI:10.1002/ejoc.200500765
日期:2006.3
The catalytic enantioselectivering-openingreaction of meso-stilbene oxide and cyclohexene oxide with anilines was catalyzed by (S)-(–)-BINOL-Ticomplexes at ambient temperature to obtain β-amino alcohols in high yield (95 %) and enantioselectivity (ee, 78 %). The enantiomeric excess (ee) of the product was further improved to 98 % by a single recrystallization step. The absolute configuration of