Metal-Free Catalytic Asymmetric Fluorination of Keto Esters Using a Combination of Hydrogen Fluoride (HF) and Oxidant: Experiment and Computation
作者:Roman Pluta、Patricia E. Krach、Luigi Cavallo、Laura Falivene、Magnus Rueping
DOI:10.1021/acscatal.7b03118
日期:2018.3.2
for the catalytic asymmetric fluorination has been developed. The catalyst was used in the asymmetric fluorination of carbonyl compounds, providing the products with a quaternary stereocenter with high enantioselectivities. Chiral hypervalent iodine difluoride intermediates were generated in situ by treatment of the catalyst with an oxidant and hydrogen fluoride as fluoride source. As such, the α-fluorination
Discovering organocatalysts with novel framework from terpenoid alkaloids is presented in this paper. Lappaconitine was found to enantioselectively catalyze α-hydroxylation of β-keto esters using tert-butyl hydroperoxide as the oxidant in chloroform to afford the corresponding products in high yields and good enantioselectivity (up to 85% ee).
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
Axially chiral C-2-symmetric N-heterocyclic carbene (NHC) palladium diaquo complexes 1a and 1b derived from (R)-BINAM are effective catalysts for the enantioselective alpha-hydroxylation of beta-keto esters using oxaziridine 2a as the oxidant to give the corresponding products in high yields along with moderate enantioselectivities (C) 2010 Elsevier Ltd All rights reserved