Catalytic asymmetric synthesis of quarternary carbon centers. Palladium-catalyzed formation of either enantiomer of spirooxindoles and related spirocyclics using a single enantiomer of a chiral diphosphine ligand
摘要:
The asymmetric synthesis of eight spirooxindoles and related spirocyclics from the corresponding aryl iodide by palladium catalyzed cyclizations in the presence of the diphosphine ligand (R)-(+)-BINAP is reported.
A series of 3,3′-disubstituted BINAP ligands are used in asymmetric inter- and intramolecular Heck/Mizoroki reactions and their enantioselectivity compared to BINAP.
Application of 3,3′-disubstituted xylBINAP derivatives in inter- and intramolecular asymmetric Heck/Mizoroki reactions
作者:Danica A. Rankic、Daniela Lucciola、Brian A. Keay
DOI:10.1016/j.tetlet.2010.08.078
日期:2010.10
3,3'-Disubstituted xylBINAP derivatives were applied to inter- and intramolecular asymmetric Heck/Mizoroki reactions. The results from these reactions were compared to those obtained with (R)-xylBINAP, (S)-BINAP and 3,3'-disubstituted BINAP derivatives. Catalysts derived from 3,3'-disubstituted xylBINAP ligands were found to be most effective in the arylation of 2,3-dihydrofuran in terms of reaction times, conversions, and product enantioselectivity. (C) 2010 Elsevier Ltd. All rights reserved.