Axially Chiral NHC−Pd(II) Complexes in the Oxidative Kinetic Resolution of Secondary Alcohols Using Molecular Oxygen as a Terminal Oxidant
作者:Tao Chen、Jia-Jun Jiang、Qin Xu、Min Shi
DOI:10.1021/ol063061w
日期:2007.3.1
see text] Axially chiral N-heterocyclic carbene (NHC) Pd(II) complexes were prepared from optically active 1,1'-binaphthalenyl-2,2'-diamine (BINAM) and H8-BINAM and applied in the oxidativekineticresolution of secondaryalcoholsusing molecular oxygen as a terminal oxidant. The corresponding sec-alcohols can be obtained in good yields with moderate to good enantioselectivities.
Chiral C2-symmetric 2,5-disubstituted pyrrolidine derivatives as catalytic chiral ligands in the reactions of diethylzinc with aryl aldehydes
作者:Min Shi、Yukihiro Satoh、Yukio Masaki
DOI:10.1039/a803336f
日期:——
Two kinds of chiral C2-symmetric 2,5-disubstituted pyrrolidine derivatives having a β-aminoalcohol moiety have been successfully synthesized and their catalytic abilities of chiral induction have been examined in the reactions of diethylzinc with arylaldehydes. The production of sec-alcohols having R-absolute configuration could be achieved in very high chemical yield (85–95%) and very high enantiomeric
Tail-Tied Ligands: An Immobilized Analogue of (R)-2-Piperidino-1,1,2-triphenylethanol with Intact High Catalytic Activity and Enantioselectivity
作者:Miquel A. Pericàs、David Castellnou、Israel Rodríguez、Antoni Riera、Lluís Solà
DOI:10.1002/adsc.200303125
日期:2003.12
A functional analogue of (R)-2-piperidino-1,1,2-triphenylethanol was synthesized and anchored to different polymeric supports by a position remote from the active region. This strategy, leading to what we call a tail-tiedligand, allows for the achievement of the optimal transition state geometry in the catalytic process. The catalyticactivity of the resulting heterogenized ligands was investigated
2-Amino-Substituted 1-Sulfinylferrocenes as Chiral Ligands in the Addition of Diethylzinc to Aromatic Aldehydes
作者:Julián Priego、Olga García Mancheño、Silvia Cabrera、Juan Carlos Carretero
DOI:10.1021/jo016271p
日期:2002.2.1
ferrocenyl sulfoxides and their use as chiral catalysts in the asymmetric addition of diethylzinc to aromaticaldehydes is described. Moderate to high enantioselectivities (up to 96% ee) were obtained in the case of the arylsulfonamide ligands (R(Fc), R(S))-4h and (R(Fc), R(S))-4i. It has been demonstrated that the planar chirality of the ferrocene unit is the decisive chiral element involved in the reaction
Synthesis of Novel 1,4-Bissulfonamide Ligands for Enantioselective Addition of Diethylzinc to Aldehydes
作者:Minghua Yang、Jiangtao Sun、Chengjian Zhu
DOI:10.1002/cjoc.201180303
日期:2011.8
Several novel chiral sulfonamide ligands based on (1R,2S,4R,5S)‐1,4‐diamino‐2,5‐dimethylcyclohexane skeleton have been synthesized and their application in the enantioselective addition of diethylzinc to aldehydes was investigated in the presence of Ti(OiPr)4. The effect of ligands, temperature and the loading amount of ligands was studied. Under optimized conditions, enantioselective addition of diethylzinc
合成了几种基于(1 R,2 S,4 R,5 S)-1,4-二氨基-2,5-二甲基环己烷骨架的新型手性磺酰胺配体,并研究了它们在二乙基锌对醛的对映选择性加成中的应用。 Ti(O i Pr)4的存在。研究了配体的影响,温度和配体的负载量。在最佳条件下,二乙基锌与各种芳基醛和脂族醛的对映选择性加成反应顺利进行,并提供了高达88%ee的手性仲醇。