Heterogeneous Chiral Copper Complexes of Amino Alcohol for Asymmetric Nitroaldol Reaction
作者:Vishal J. Mayani、Sayed H. R. Abdi、Rukhsana I. Kureshy、Noor-ul H. Khan、Anjan Das、Hari C. Bajaj
DOI:10.1021/jo1010679
日期:2010.9.17
Chiral amino alcohols supported on mesoporous silicas were synthesized and evaluated as a new class of chiral ligands in copper-catalyzed nitroaldol reaction under heterogeneous and mild reaction conditions. The activity and enantioselectivity of the present catalytic system is immensely influenced by the presence of achiral and chiral bases as an additive. The heterogenized chiral copper(II) complex of amino alcohol was found to be an effective recyclable catalyst for the nitroaldol reaction of different aldehydes such as aromatic, aliphatic, alicyclic, and alpha-beta unsaturated aldehydes to produce nitroaldol products with remarkably high enantioselectivity (>= 99%) and yields.
A New Catalyst for the Asymmetric Henry Reaction: Synthesis of β-Nitroethanols in High Enantiomeric Excess
作者:James D. White、Subrata Shaw
DOI:10.1021/ol3030023
日期:2012.12.21
has been designed and synthesized from cis-2,5-diaminobicyclo[2.2.2]octane. The complex generated in situ by the interaction of the ligand with (CuOTf)2·C6H5CH3 was an efficient catalyst for the asymmetric Henry reaction, producing nitroaldol products in high yield and good stereoselectivity. Henry reactions catalyzed by this tetrahydrosalen-Cu(I) complex led to syntheses of β-adrenergic blocking agents
从顺-2,5-二氨基双环[2.2.2]辛烷设计并合成了一种新的手性四氢salen配体。通过配体与(CuOTf)2 ·C 6 H 5 CH 3的相互作用原位生成的配合物是用于不对称亨利反应的有效催化剂,可以高收率和良好的立体选择性生产硝基醛醇产物。该四氢salen -Cu(I)配合物催化的亨利反应导致β-肾上腺素能阻断剂(S)-甲苯酚,(S)-莫普洛尔和(S)-丙醇的合成。