Catalytic, Enantioselective α‐Alkylation of Azlactones with Nonconjugated Alkenes by Directed Nucleopalladation
作者:Sri Krishna Nimmagadda、Mingyu Liu、Malkanthi K. Karunananda、De‐Wei Gao、Omar Apolinar、Jason S. Chen、Peng Liu、Keary M. Engle
DOI:10.1002/anie.201814272
日期:2019.3.18
palladium(II)‐catalyzed enantioselective α‐alkylation of azlactones with nonconjugated alkenes is described. The reaction employs a chiral BINOL‐derived phosphoric acid as the source of stereoinduction, and a cleavable bidentate directing group appended to the alkene to control the regioselectivity and stabilize the nucleopalladated alkylpalladium(II) intermediate in the catalytic cycle. A wide range of
Asymmetric trifluoromethylthiolation of azlactones under chiral phase transfer catalysis
作者:Marina Sicignano、Ricardo I. Rodríguez、Vito Capaccio、Fabio Borello、Rafael Cano、Francesco De Riccardis、Luca Bernardi、Sergio Díaz-Tendero、Giorgio Della Sala、José Alemán
DOI:10.1039/d0ob00476f
日期:——
The first enantioselective method for the installation of the SCF3 group at the C-4 position of azlactones is described in the present communication under quinidinium phasetransfercatalysis. The higher performance of substrates containing electron-rich 2-aryl groups at the azlactone was rationalized using DFT calculations.
A bifunctional squaramide-catalyzed reaction of azlactones and o-quinone methides in situ generatedfrom 2-(1-tosylalkyl)-phenols has been succesfully developed under basic condition, providing an efficient and mild access to chiral dihydrocoumarins...
An asymmetric inverse-electron-demandhetero-Diels-Alderreaction between o-quinone methides and azlactones to generate potentially pharmacological active dihydrocoumarins has been achieved efficiently by using a chiral N,N'-dioxide-Sc(III) complex as the catalyst. The desired products were obtained in high yields with excellent enantioselectivities and diastereoselectivities (up to 94% yield, 96%
PROCESSES FOR THE PREPARATION OF SUBSTITUTED TETRAHYDRO BETA-CARBOLINES
申请人:Hwang Peter Seongwoo
公开号:US20120136154A1
公开(公告)日:2012-05-31
Provided herein are improved processes for the synthesis of substituted tetrahydro beta-carboline derivatives. In particular, provided herein are improved processes useful for the preparation of (S)-4-chlorophenyl 6-chloro-1-(4-methoxyphenyl)-3,4-dihydro-1H-pyrido[3,4-
b
]indole-2(9H)-carboxylate. Formula (I)