Asymmetric Synthesis of 2-Aryl-2,3-dihydro-4-quinolones via Bifunctional Thiourea-Mediated Intramolecular Cyclization
摘要:
A novel asymmetric preparation of optically enriched 2-aryl-2,3-dihydroquinolin-4(1H)-ones has been developed. By installing a sulfonyl group on the nitrogen of the anilines and an ester function on the unsaturated ketones, an intramolecular organocatalytic cyclization took place readily in a stereoselective manner, resulting in the formation of dihydroquinolones with high enantioselectivity.
Enantioselective Synthesis of Azaflavanones Using Organocatalytic 6-<i>endo</i>Aza-Michael Addition
作者:Shuanghua Cheng、Lili Zhao、Shouyun Yu
DOI:10.1002/adsc.201300920
日期:2014.3.24
A method to prepare highly enantioenriched azaflavanonesusing an organocatalytic 6‐endo aza‐Michael addition has been described. A variety of 2‐aryl‐, 2‐vinyl‐ and 2‐methylazaflavanones were prepared in good yields (53–84%) and excellent enantioselectivities (97.6:2.4 to 99.3:0.7 er).
Per-6-amino-β-cyclodextrin as a Chiral Base Catalyst Promoting One-Pot Asymmetric Synthesis of 2-Aryl-2,3-dihydro-4-quinolones
作者:Kuppusamy Kanagaraj、Kasi Pitchumani
DOI:10.1021/jo302173a
日期:2013.1.18
A highly efficient one-pot synthesis of enantiomerically enriched 2-aryl-2,3-dihydroquinolin-4(1H)-ones has been carried out for the first time using per-6-ABCD as a supramolecular host, chiral base catalyst, and a reusable promoter to give the corresponding scaffold with high yield (up to 99%) and enantiomeric excess (up to 99%). The catalyst is recovered and reused without loss in its activity.