BINOL-phosphoric acid catalyzed asymmetric Mannich addition of β-ketoesters to indolenines generated in situ by DDQ
作者:Boora Ramesh、G. Ravi Kumar、Suresh Yarlagadda、B. Sridhar、B.V. Subba Reddy
DOI:10.1016/j.tet.2019.130620
日期:2019.11
asymmetric Mannich addition of β-ketoesters to indolenines that were generated in situ from 3-indolinone-2-carboxylates by DDQ has been developed using a catalytic amount of chiral BINOL-phosphoric acid. The corresponding chiral 3-indolinone-2-carboxylate derivatives were obtained in good yields with excellent ee (up to 99%). This is the first report on the enantioselective addition of β-ketoesters to
Construction of Vicinal All-Carbon Stereogenic Centers via Copper-Catalyzed Asymmetric Decarboxylative Propargylation: Enantio- and Diastereoselective Synthesis of Substituted Spirolactones
The formation of vicinal all-carbonquaternarystereocenters remains a formidable challenge. We report herein the synthesis of such highly congested structural dyads by copper-catalyzed decarboxylative propargylation between propargyl carbonates and indanone-based nucleophiles. The implementation of diphenylethylenediamine (DPEN)-based ligands is the key to success. A wide range of functional groups
Palladium-Catalyzed Stereoselective Construction of 1,3-Stereocenters Displaying Axial and Central Chirality via Asymmetric Alkylations
作者:Aiqi Xue、Xingfu Wei、Yue Huang、Jingping Qu、Baomin Wang
DOI:10.3390/molecules28072927
日期:——
challenge. Herein, we report the development of stereoselective union of a point chiral center with allenyl axial chirality in 1,3-position by Pd-catalyzed asymmetric allenylic alkylation between racemic allenyl carbonates and indanone-derived β-ketoesters. Various target products bearing a broad range of functional groups were afforded in high yield (up to 99%) with excellent enantioselectivities (up to
Aromatic 1,3-dicarbonyl compounds react with not enolizable aldehydes in the presence of C2H5MgBr or AlCl3 affording 2-carbethoxy- and 2-acetyl-1-indanones via tandem Knoevenagel condensation-cycloalkylation process.
Friedel-crafts coordinated processes: 1-Oxoindanes from aromatic β-dicarbonyl compounds and aldehydes
Variously substituted 1-oxoindanes were synthesized by highly selective bis-alkylation of aromatic beta-dicarbonyl compounds with non enolizable aldehydes.