Rapid and Regioselective Hydrogenation of α,β-Unsaturated Ketones and Alkylidene Malonic Diesters Using Hantzsch Ester Catalyzed by Titanium Tetrachloride
作者:Yulin Lam、Jun Che
DOI:10.1055/s-0030-1258556
日期:2010.10
A regioselective hydrogenation of α,β-unsaturated ketones and alkylidenemalonic diesters using Hantzsch ester as the reducing agent and titanium tetrachloride as a catalyst is described. The short reaction times and mild reaction conditions are the advantages of this method.
Basic CuCO<sub>3</sub>
/ligand as a new catalyst for 'on water' borylation of Michael acceptors, alkenes and alkynes: application to the efficient asymmetric synthesis of β-alcohol type sitagliptin side chain
作者:Gaj Stavber、Zdenko Časar
DOI:10.1002/aoc.2957
日期:2013.3
The efficient 'on water' β‐borylation using bis(pinacolato)diboron agent was achieved with a newly developed catalytic system based on basic copper carbonate and various ligands. The catalytic system was used for β‐borylation of various Michael acceptors, alkenes and alkynes. The presented methodology was successfully applied to the novel synthesis of β‐alcohol type sitagliptin side chain precursor
Kinetic Resolution of β-Hydroxy Carbonyl Compounds via Enantioselective Dehydration Using a Cation-Binding Catalyst: Facile Access to Enantiopure Chiral Aldols
作者:Sushovan Paladhi、In-Soo Hwang、Eun Jeong Yoo、Do Hyun Ryu、Choong Eui Song
DOI:10.1021/acs.orglett.8b00547
日期:2018.4.6
β-hydroxy carbonyl (aldol) compounds through enantioselective dehydration process was developed using a cation-binding Song’s oligoethylene glycol (oligoEG) catalyst with potassium fluoride (KF) as base. A wide range of racemic aldols was resolved with extremely high selectivity factors (s = up to 2393) under mild reaction conditions. This protocol is easily scalable. It provides an alternative approach for
Palladium Nanoparticles Supported on Fibrous-Structured Silica Nanospheres (KCC-1): An Efficient and Selective Catalyst for the Transfer Hydrogenation of Alkenes
作者:Ziyauddin S. Qureshi、Pradip B. Sarawade、Matthias Albert、Valerio D'Elia、Mohamed N. Hedhili、Klaus Köhler、Jean-Marie Basset
DOI:10.1002/cctc.201402781
日期:2015.2
An efficient palladium catalyst supported on fibroussilica nanospheres (KCC‐1) has been developed for the hydrogenation of alkenes and α,β‐unsaturated carbonyl compounds, providing excellent yields of the corresponding products with remarkable chemoselectivity. Comparison (high‐resolution TEM, chemisorption) with analogous mesoporous (MCM‐41, SBA‐15) silica‐supported Pd nanocatalysts prepared under
Catalytic asymmetric trifluoromethylthiolation of carbonyl compounds <i>via</i> a diastereo and enantioselective Cu-catalyzed tandem reaction
作者:Ming Yu Jin、Juncheng Li、Renke Huang、Yuxuan Zhou、Lung Wa Chung、Jun (Joelle) Wang
DOI:10.1039/c8cc02097c
日期:——
α-trifluoromethylthiolation of carbonyl compounds. The present study describes a diastereo and enantioselective Cu-catalyzed tandem 1,4-addition/trifluoromethylthiolation of acyclic enones. The tandem reaction enables the asymmetric integration of the –SCF3 group to carbonyl compounds, establishing chiral tertiary α-carbon centers and affording α-SCF3-β-substituted carbonyl compounds in 50–92% yields with up to 20 : 1