Cu-catalyzed asymmetric Henry reaction promoted by chiral camphor Schiff bases
作者:Tangqian Jiao、Jingxuan Tu、Gaoqiang Li、Feng Xu
DOI:10.1016/j.molcata.2016.02.004
日期:2016.5
Abstract Five novel chiral camphor Schiffbases have been synthesized and utilized as ligands in asymmetric Henry reaction between nitromethane and aldehydes. The diastereoisomeric Schiffbases 5a and 5a' were separated successfully and gave completely different absolute configurations in the reaction. The reactions were carried out with CuCl-Schiff base 5a complex under mild condition with good yields
alcohol–CuII catalyst: Highlyenantioselective Henry reactions between aromatic aldehydes and nitromethane have been developed. The reactions were catalyzed by an easily available and operationally simple amino alcohol–copper(II) catalyst (see scheme). In total, 38 substrates were tested and the R‐configured products were obtained in good yields with excellent enantioselectivities.
氨基醇-Cu II 催化剂:已开发出芳香醛与硝基甲烷之间的高度对映选择性的亨利反应。反应是由易于获得且操作简单的氨基醇-铜(II)催化剂催化的(请参见方案)。总共测试了38种底物,并以高收率和出色的对映选择性获得了R构型的产品。
Copper-Chiral Camphor <i>β</i>
-Amino Alcohol Complex Catalyzed Asymmetric Henry Reaction
作者:Feng Xu、Chao Lei、Lei Yan、Jingxuan Tu、Gaoqiang Li
DOI:10.1002/chir.22498
日期:2015.10
Four novel chiral amino alcohols were synthesized from D‐(+)‐camphor and utilized as ligands in a Cu(I)‐catalyzedasymmetricHenryreaction. The reactions were carried out under mild conditions with excellent enantioselectivities and moderate yields without the exclusion of air or moisture. The highest enantioselectivity was observed up to 94% enantiomeric excess (ee) with ligand L1 in toluene at room