Synthesis of 4-Hydroxy-4H-chromenes by Reaction of Salicylic Aldehydes with Alkynals Catalyzed by Silyl Prolinol Ethers
作者:José Alemán、José García Ruano、Cuauhtémoc Alvarado、Vanesa Marcos、Alberto Núñez
DOI:10.1055/s-0030-1260020
日期:2011.6
report an oxa-Michael/Baylis-Hillman tandem reaction between salicylaldehydes and alk-2-ynals activated by silyl prolinol ethers, affording 2,3-disubstituted 4-hydroxy-4H-chromenes in good yields and enantiomeric ratios (up to 98:2). organocatalysis - proline - chromenes - asymmetricsynthesis - aminocatalysis