scholarly journals Ligand-Promoted Iridium-Catalyzed Transfer Hydrogenation of Terminal Alkynes with Ethanol and Its Application

ACS Omega ◽  
2019 ◽  
Vol 4 (14) ◽  
pp. 16045-16051 ◽  
Author(s):  
Chengniu Wang ◽  
Shengnan Gong ◽  
Zhipeng Liang ◽  
Yufeng Sun ◽  
Rui Cheng ◽  
...  
Catalysts ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Hui-Ju Chen ◽  
Chien-Cheng Chiu ◽  
Tsui Wang ◽  
Dong-Sheng Lee ◽  
Ta-Jung Lu

The bis-NHC–Ag/Pd(OAc)2 catalytic system (NHC = N-heterocyclic carbene), a combination of bis-NHC–Ag complex and Pd(OAc)2, was found to be a smart catalyst in the Pd-catalyzed transfer hydrogenation of various functionalized arenes and internal/terminal alkynes. The catalytic system demonstrated high efficiency for the reduction of a wide range of various functional groups such as carbonyls, alkynes, olefins, and nitro groups in good to excellent yields and high chemoselectivity for the reduction of functional groups. In addition, the protocol was successfully exploited to stereoselectivity for the transformation of alkynes to alkenes in aqueous media under air. This methodology successfully provided an alternative useful protocol for reducing various functional groups and a simple operational protocol for transfer hydrogenation.


2017 ◽  
Vol 15 (26) ◽  
pp. 5462-5467 ◽  
Author(s):  
Ji-Shu Zhang ◽  
Jian-Qiu Zhang ◽  
Tieqiao Chen ◽  
Li-Biao Han

A novel and efficient t-BuOK-mediated reductive addition of P(O)–H compounds to terminal alkynes forming β-arylphosphine oxides was developed. This reaction may proceed via a tandem process involving regio-selective addition and subsequent transfer hydrogenation.


2001 ◽  
Vol 79 (5-6) ◽  
pp. 915-921 ◽  
Author(s):  
Yuan Gao ◽  
Michael C Jennings ◽  
Richard J Puddephatt

The diruthenium(0) complex [Ru2(µ-CO)(CO)4(µ-dppm)2] (1) (dppm = Ph2PCH2PPh2), is a catalyst for the transfer hydrogenation, using formic acid as hydrogen donor, of the alkynes PhCºCPh, PhCºCMe, EtCºCEt, and PrCºCPr but not of the terminal alkynes HCºCH, PhCºCH, BuCºCH, or the alkynes containing one or two electron-withdrawing substituents PhCºCCO2Me and MeO2CCtriple bondCCO2Me. In the successful reactions, the formic acid is first decomposed to carbon dioxide and hydrogen, which then hydrogenates the alkynes in a slower reaction. In the unsuccessful reactions, the decomposition of formic acid is strongly retarded by the alkyne. In the case with the alkyne PhCºCH, it is shown that the alkyne reacts with protonated 1 to give first [Ru2(µ-CPh=CH2)(CO)4(µ-dppm)2][HCO2], which then isomerizes to give the catalytically inactive, stable complex [Ru2(µ-CH=CHPh)(CO)4(µ-dppm)2][HCO2]. This complex has been structurally characterized and both of the µ-styrenyl complexes are shown to be fluxional in solution.Key words: ruthenium, hydrogenation, catalysis, binuclear..


2012 ◽  
Vol 48 (40) ◽  
pp. 4827 ◽  
Author(s):  
Gerrit Wienhöfer ◽  
Felix A. Westerhaus ◽  
Rajenahally V. Jagadeesh ◽  
Kathrin Junge ◽  
Henrik Junge ◽  
...  

ChemInform ◽  
2012 ◽  
Vol 43 (36) ◽  
pp. no-no
Author(s):  
Gerrit Wienhoefer ◽  
Felix A. Westerhaus ◽  
Rajenahally V. Jagadeesh ◽  
Kathrin Junge ◽  
Henrik Junge ◽  
...  

2020 ◽  
Vol 16 ◽  
Author(s):  
Lucas da Silva Santos ◽  
Matheus Fillipe Langanke de Carvalho ◽  
Ana Claudia de Souza Pinto ◽  
Amanda Luisa da Fonseca ◽  
Julio César Dias Lopes ◽  
...  

Background: Malaria greatly affects the world health, having caused more than 228 million cases only in 2018. The emergence of drug resistance is one of the main problems in its treatment, demonstrating the urge for the development of new antimalarial drugs. Objective: Synthesis and in vitro antiplasmodial evaluation of triazole compounds derived from isocoumarins and a 3,4- dihydroisocoumarin. Method: The compounds were synthesized in 4 to 6-step reactions with the formation of the triazole ring via the Copper(I)-catalyzed 1,3-dipolar cycloaddition between isocoumarin or 3,4-dihydroisocoumarin azides and terminal alkynes. This key reaction provided compounds with an unprecedented connection of isocoumarin or 3,4-dihydroisocoumarin and the 1,2,3-triazole ring. The products were tested for their antiplasmodial activity against a Plasmodium falciparum chloroquine resistant and sensitive strains (W2 and 3D7, respectively). Results: Thirty-one substances were efficiently obtained by the proposed routes with an overall yield of 25-53%. The active substances in the antiplasmodial test displayed IC50 values ranging from 0.68-2.89 μM and 0.85-2.07 μM against W2 and 3D7 strains, respectively.


2015 ◽  
Vol 48 (7) ◽  
pp. 2140-2150 ◽  
Author(s):  
Florian Klappenberger ◽  
Yi-Qi Zhang ◽  
Jonas Björk ◽  
Svetlana Klyatskaya ◽  
Mario Ruben ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document