108837-17-8Relevant articles and documents
Highly enantioselective addition of aliphatic aldehydes to 2-hydroxychalcone enabled by cooperative organocatalysts
Chen, Le,Chen, Lu,Gao, Yu-Qi,Hou, Yi,Hu, Jiadong,Wen, Wen,Xie, Weiqing,Xu, Dongyang
supporting information, p. 10018 - 10021 (2020/09/15)
Herein, we developed an enantioselective addition of aliphatic aldehydes to 2-hydroxychalcone promoted by cooperative organocatalysts, giving access to hybrid flavonoids in excellent enantioselectivities. This reaction took advantage of cycloisomerization of 2-hydroxychalcone to form a transient flavylium under the irradiation of 24 W CFL, which was trapped by the in situ generated chiral enamine intermediate. The synergistic action of chiral phosphoric acid secured the excellent outcome of this reaction by ion-pairing with the transient flavylium.
ZrCl4-catalysed synthesis of new 4-(2-hydroxyphenyl)pyrazolo[3,4-b]pyridine derivatives
Liu, Meilin,Yin, Guodong
, p. 236 - 266 (2015/06/02)
In the presence of a catalytic amount of zirconium(IV) chloride, an efficient synthesis of new 4-(2-hydroxyphenyl)pyrazolo[3,4-b]pyridines has been developed by the reaction 2-hydroxychalcones with 3-methyl-1-phenyl-1H-pyrazol-5-amine in refluxing ethanol. All these novel compounds have been characterised by 1H NMR, 13C NMR, HRMS, IR spectra and X-ray crystallographic analysis.
Enantioselective intramolecular formal [2 + 4] annulation of acrylates and α,β-unsaturated imines catalyzed by amino acid derived phosphines
Jin, Zhichao,Yang, Ruojie,Du, Yu,Tiwari, Bhoopendra,Ganguly, Rakesh,Chi, Yonggui Robin
, p. 3226 - 3229 (2012/08/08)
The first chiral phosphine-catalyzed activation of acrylates for intramolecular formal [2 + 4] reactions with unsaturated imines is described. The catalytic reactions afford N-heterocycles with exceptionally high diastereo- and enantioselectivities. The [2 + 4] products are amenable for further transformations to useful molecules such as chiral piperidines and multicyclic structures.