Highly Diastereo- and Enantioselective Ir-Catalyzed Hydrogenation of 2,3-Disubstituted Quinolines with Structurally Fine-Tuned Phosphine–Phosphoramidite Ligands
作者:Xin-Hu Hu、Xiang-Ping Hu
DOI:10.1021/acs.orglett.9b03925
日期:2019.12.20
diastereo- and enantioselectiveIr-catalyzedhydrogenation of unfunctionalized 2,3-disubstituted quinolines, especially 3-alkyl-2-arylquinolines, has been realized. The success of this hydrogenation is ascribed to the use of a structurally fine-tuned chiral phosphine-phosphoramidite ligand with a (Sa)-3,3'-dimethyl H8-naphthyl moiety and (Rc)-1-phenylethylamine backbone. The hydrogenation displayed broad
The α-alkylation of ketones using an earth-abundant and nonprecious NiBr2/L1 system is reported. This nickel-catalyzed reaction could be performed in gram scale and successfully applied in the synthesis of donepezil (Alzheimer’s drug) and functionalization of steroid hormones and fatty acid derivatives. Synthesis of N-heterocycles, methylation of ketones, and one-pot double alkylation to bis-hetero
LiOtBu was found to efficiently promote the α-alkylation reaction of ketones with primary alcohols, without the addition of any transition metal catalyst.
Enantioselective Metal-Free Hydrogenations of Disubstituted Quinolines
作者:Zhenhua Zhang、Haifeng Du
DOI:10.1021/acs.orglett.5b03307
日期:2015.12.18
A metal-freehydrogenation of 2,4-disubstituted quinolines was realized for the first time using chiral diene derived borane catalysts to furnish the corresponding tetrahydroquinolines in 75–98% yields with 95/5−99/1 dr’s and 86–98% ee’s. This catalytic system was also effective for 2,3-disubstituted quinolines to give moderate to good ee’s.