Direct C–H sulfenylation of quinoxalinones with thiols under visible-light-induced photocatalyst-free conditions

2019 ◽  
Vol 21 (23) ◽  
pp. 6241-6245 ◽  
Author(s):  
Qing-Hu Teng ◽  
Yan Yao ◽  
Wen-Xiu Wei ◽  
Hai-Tao Tang ◽  
Jia-Rong Li ◽  
...  
Keyword(s):  
Visible Light ◽  
Metal Free ◽  
Catalyst Free

We have developed a metal-free and catalyst-free visible-light-promoted direct C–H sulfenylation of quinoxalin-2(1H)-ones with thiols for the synthesis of diverse 3-sulfenylquinoxalin-2(1H)-ones.

Metal-Free Photoinduced Hydroalkylation Cascade Enabled by an Electron-Donor-Acceptor Complex

2020 ◽  
Author(s):  
José Tiago Menezes Correia ◽  
Gustavo Piva da Silva ◽  
Camila Menezes Kisukuri ◽  
Elias André ◽  
Bruno Pires ◽  
...  
Keyword(s):  
Electron Donor ◽  
Functional Group ◽  
Photoexcited Electron ◽  
One Pot ◽  
Quaternary Centers ◽  
Metal Free ◽  
Acceptor Complex ◽  
Catalyst Free ◽  
Donor Acceptor ◽  
Radical Cascade

A metal- and catalyst-free photoinduced radical cascade hydroalkylation of 1,7-enynes has been disclosed. The process is triggered by a SET event involving a photoexcited electron-donor-aceptor complex between NHPI ester and Hantzsch ester, which decomposes to afford a tertiary radical that is readily trapped by the enyne. <a>The method provides an operationally simple, robust and step-economical approach to the construction of diversely functionalized dihydroquinolinones bearing quaternary-centers. A sequential one-pot hydroalkylation-isomerization approach is also allowed giving access to a family of quinolinones. A wide substrate scope and high functional group tolerance was observed in both approaches</a>.

Regioselective C3-H Trifluoromethylation of 2H-Indazole Under Transition-Metal-Free Photoredox Catalysis

2019 ◽  
Author(s):  
Arumugavel Murugan ◽  
Venkata Nagarjuna Babu ◽  
Nagaraj Sabarinathan ◽  
Sharada Duddu. S
Keyword(s):  
Transition Metal ◽  
Visible Light ◽  
Practical Approach ◽  
Hypervalent Iodine ◽  
Radical Mechanism ◽  
Photoredox Catalysis ◽  
Metal Free

Here we report a visible-light-promoted metal-free regioselective C3-H trifluoromehtylation reaction that proceeds via radical mechanism and which supported by control experiments. The combination of photoredox catalysis and hypervalent iodine reagent provides a practical approach for the present trifluoromethylation reaction and synthesis of a library of trifluoromethylated indazoles.

Metal‐Free and Heterogeneous Photocatalytic Reduction of 4‐Nitroaniline by a Poly(Ethylene Glycol)‐Supported Eosin Dye under Visible‐Light Exposure

ChemCatChem ◽  
2019 ◽  
Vol 11 (14) ◽  
pp. 3307-3317
Author(s):  
Andreea L. Chibac ◽  
Violeta Melinte ◽  
Vlasta Brezová ◽  
Estelle Renard ◽  
Arnaud Brosseau ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Visible Light ◽  
Light Exposure ◽  
Photocatalytic Reduction ◽  
Poly Ethylene Glycol ◽  
Metal Free ◽  
Poly Ethylene

Catalyst-free synthesis of phenanthridines via electrochemical coupling of 2-isocyanobiphenyls and amines

2021 ◽  
Vol 45 (14) ◽  
pp. 6367-6378
Author(s):  
Bhanwar Kumar Malviya ◽  
Karandeep Singh ◽  
Pradeep K. Jaiswal ◽  
Manvika Karnatak ◽  
Ved Prakash Verma ◽  
...  
Keyword(s):  
One Pot ◽  
Metal Free ◽  
Catalyst Free ◽  
Electrochemical Coupling

One pot metal-free synthesis of phenanthridines and amides under electrochemical conditions.

Highly chemoselective deoxygenation of N-heterocyclic N-oxides under transition metal-free conditions

2021 ◽  
Vol 19 (16) ◽  
pp. 3735-3742
Author(s):  
Se Hyun Kim ◽  
Ju Hyeon An ◽  
Jun Hee Lee
Keyword(s):  
Transition Metal ◽  
Visible Light ◽  
Eosin Y ◽  
Metal Free ◽  
Simple Protocol

Here, we provide an operationally simple protocol for the highly chemoselective deoxygenation of various functionalized N-heterocyclic N-oxides under visible light-mediated photoredox conditions with Na2-eosin Y as an organophotocatalyst.

Visible-light-initiated Catalyst-free Oxidative Cleavage of Triaryl-Substituted Alkenes C=C Bonds under Ambient Conditions

2021 ◽  
Author(s):  
Wenjing Li ◽  
Shun Li ◽  
Lihua Luo ◽  
Yichen Ge ◽  
Jiaqi Xu ◽  
...  
Keyword(s):  
Visible Light ◽  
Room Temperature ◽  
Ambient Air ◽  
Oxidative Cleavage ◽  
Ambient Conditions ◽  
Blue Led ◽  
Catalyst Free

The catalyst-free oxidative cleavage of (Z)-triaryl-substituted alkenes bearing pyridyl motif with ambient air under irradiation of blue LED at room temperature has been developed. The reaction was facile and scalable,...

Metal-free visible-light-induced aerobic oxidation of α-diazoesters leading to α-ketoesters in air

2021 ◽  
Author(s):  
Ruisheng Liu ◽  
Qishun Liu ◽  
Haoran Meng ◽  
Hongyu Ding ◽  
Jindong Hao ◽  
...  
Keyword(s):  
Visible Light ◽  
Room Temperature ◽  
Aerobic Oxidation ◽  
Metal Free

A metal-free and visible-light-induced strategy has been established for the construction of α-ketoesters via aerobic oxidation of α-diazoesters with dioxygen in air at room temperature.

scholarly journals Metal-Free Catalysts for the Polymerization of Alkynyl-Based Monomers

Catalysts ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 1 ◽  
Author(s):  
Jie Zhang ◽  
Zhiming Zhang ◽  
Fulin Yang ◽  
Haoke Zhang ◽  
Jingzhi Sun ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Research Focus ◽  
Catalytic Systems ◽  
Metal Free ◽  
Catalyst Free ◽  
Material Sciences ◽  
Acid Catalyzed

Novel polymerizations based on alkyne monomers are becoming a powerful tool to construct polymers with unique structures and advanced functions in the areas of polymer and material sciences, and scientists have been attracted to develop a variety of novel polymerizations in recent decades. Therein, catalytic systems play an indispensable role in the influence of polymerization efficiencies and the performances of the resultant polymers. Concerning the shortcomings of metallic catalysts, much of the recent research focus has been on metal-free polymerization systems. In this paper, metal-free catalysts are classified and the corresponding polymerizations are reviewed, including organobase-catalyzed polymerizations, Lewis-acid-catalyzed polymerizations, as well as catalyst-free polymerizations. Moreover, the challenges and perspectives in this area are also briefly discussed.

Visible-Light-Mediated Organoboron-Catalysed Metal-Free Dehydrogenation of N-Heterocycles Using Molecular Oxygen

2021 ◽  
Author(s):  
Lanfeng Wei ◽  
Yu Wei ◽  
Jinli Zhang ◽  
Liang Xu
Keyword(s):  
Visible Light ◽  
Molecular Oxygen ◽  
The Other ◽  
Metal Free ◽  
Other Hand

The surge of photocatalytic transformation not only provides unprecedented synthetical methods, but also triggers the enthusiasm for more sustainable photocatalysts. On the other hand, oxygen is an ideal oxidant in...

Sign in / Sign up

Export Citation Format

Share Document