ChemInform Abstract: Asymmetric Organocatalytic Tandem Cyclization/Transfer Hydrogenation: A Synthetic Strategy for Enantioenriched Nitrogen Heterocycles.

Abstract

BINOL--derived phosphonic acids are described as catalysts for the cyclization of phenylenediamines with substituted glyoxals followed by transfer hydrogenation with Hantzsch ester to give enantioenriched tetrahydroquinoxalines in good yields. The process can be readily extended to the synthesis of dihydroquinoxalinones from ethyl 2-oxo-2-arylacetates. -(SHI*, F.; TAN, W.; ZHANG, H.-H.; LI, M.; YE, Q.; MA, G.-H.; TU, S.-J.; LI, G.; Adv. Synth. Catal. 355 (2013) 18, 3715-3726, http://dx.doi.org/10.1002/adsc.201300576 ; Coll. Chem. Chem. Eng., Xuzhou Norm. Univ., Jiangsu, Xuzhou 221116, Peop. Rep. China; Eng.) -Mais 21-187