A Metal-Free and Ionic Liquid-Catalyzed Aerobic Oxidative Bromination in Water

2015 ◽  
Vol 68 (3) ◽  
pp. 513 ◽  
Author(s):  
Jian Wang ◽  
Shu-Bin Chen ◽  
Shu-Guang Wang ◽  
Jing-Hua Li

A metal-free aerobic oxidative bromination of aromatic compounds in water has been developed. Hydrobromic acid is used as a bromine source and 2-methylpyridinium nitrate ionic liquid is used as a recyclable catalyst. Water is used as the reaction mediate. This is the first report of aerobic oxidative bromination using only catalytic amount of metal-free catalyst. This system shows not only high bromine atom economy, but also high bromination selectivity. The possible mechanism and the role of the catalyst in this system have also been discussed.

2019 ◽  
Vol 44 (5-6) ◽  
pp. 267-270
Author(s):  
Ming-Fang Li ◽  
Jian Wang ◽  
Yong-Xin Ke ◽  
Song-Cheng Pan ◽  
Hong Yin ◽  
...  

An aerobic oxidative bromination of anilines and aryl ketones catalyzed by recyclable 2-methylpyridinium nitrate ionic liquid is achieved in water using hydrobromic acid as the bromine source and molecular oxygen as the oxidant. The catalytic system shows good efficiency and atom economy.


2021 ◽  
Vol 18 ◽  
Author(s):  
Seyed Sajad Sajadikhah ◽  
Bagher Liravi-Deylami

: Benzoimidazopyrimidine, benzimidazoloquinazolinone, triazolopyrimidine, and triazoloquinazolinone derivatives were synthesized via a one-pot multi-component reaction in the presence of a catalytic amount of oxalic acid dihydrate. The reactions were performed in the mixture of EtOH: H2O or under solvent-free conditions as green media. The advantageous features of these methodologies are inexpensive starting materials and catalyst, high atom economy and good yields, and metal-free synthesis. Moreover, all the products were obtained by simple filtration with no need for column chromatography or tedious separation procedures, which is very important in terms of reducing environmental pollutions.


Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 642 ◽  
Author(s):  
Mayur Thul ◽  
Yao-Peng Wu ◽  
Yi-Jyun Lin ◽  
Shu-Lin Du ◽  
Hsin-Ru Wu ◽  
...  

Tunable aryl imidazolium ionic liquids acting as Brønsted acid ionic liquids were found to be efficient catalysts for per-O-acetylation and reductive ring opening of benzylidene acetals. This method requires a truly catalytic amount of the least expensive available ionic liquids that are water-stable and reusable and also stable at room temperature. The reactions were obtained in one hour with good to excellent yields. These reactions can form C−O and C−H bonds with a high atom economy. Furthermore, the ionic liquid is an anomeric selective catalyst in per-O-acetylation and reductive ring opening of benzylidene acetals of sugar moieties.


2017 ◽  
Vol 53 (63) ◽  
pp. 8850-8853 ◽  
Author(s):  
Yingying Yang ◽  
Honglei Fan ◽  
Qinglei Meng ◽  
Zhaofu Zhang ◽  
Guanying Yang ◽  
...  

Ionic liquids can effectively induce the transformation of lignin model compounds into aromatic compounds by aerobic oxidation under metal-free conditions.


2013 ◽  
Vol 91 (12) ◽  
pp. 1262-1265 ◽  
Author(s):  
Ryan Mack ◽  
Grant Askins ◽  
Jacob Lowry ◽  
Nathan Hurley ◽  
Perry C. Reeves

An environmentally friendly method for alkylating aromatic compounds with simple alcohols in the presence of a catalytic amount of indium(III) triflate is reported. Ionic liquids are used as solvents and energy-efficient heating is provided by microwave radiation. Good yields are obtained with benzyl, secondary, and tertiary alcohols. Simple primary alcohols are not effective alkylating agents under these conditions. With tertiary alcohols, activated aromatic compounds such as toluene and anisole must be used to obtain good yields. The catalyst, which is immobilized in a water-insoluble ionic liquid, can be easily recycled without significant loss of activity.


2019 ◽  
Author(s):  
Łukasz Ciszewski ◽  
Jakub Durka ◽  
Dorota Gryko

This article describes direct photoalkylation of electron-rich aromatic compounds with diazo compoiunds. C-2 alkylated indoles and pyrroles are obtained with good yields even though the photocatalyst (Ru(bpy)3Cl2) loading is as low as 0.075 mol %. For substrates bearing electron-withdrawing substituents the addition of a catalytic amount of N,N-dimethyl-4-methoxyaniline is required. Both EWG-EWG and EWG-EDG substituted diazo esters are suitable as alkylating agents. The reaction selectivity and mechanistic experiments suggest that carbenes/carbenoid intermediates are not involved in the reaction pathway, instead radical formation is proposed.


Author(s):  
Putri Ananda Sari ◽  
Abdul Kadir ◽  
Beby Mashito Batu Bara

This study aims to determine the role of the Ombudsman of the Republic of Indonesia in North Sumatra Representative in the Supervision of Population and Civil Registry Service in Medan City. This study uses a qualitative approach with descriptive methods describing information about the data obtained from the field in the form of written and oral data from the parties studied. Data is collected based on interviews and documentation. The results of this study indicate that the role of the Ombudsman of the Republic of Indonesia in North Sumatra was carried out in the form of external supervision. External supervision is supervision carried out by the Ombudsman of the Republic of Indonesia Representative of North Sumatra to the Medan Population and Civil Registry Service. Actions taken in the supervision process are incoming reports, follow-up of the first report and follow-up of the report. Based on the research that has been carried out, it has been concluded that the role of the Ombudsman of the Republic of Indonesia in the North Sumatra Representative in supervising the service provider of the Population and Civil Registry services is carried out in the form of external supervision. In supervising the handling of public reports of alleged poor service in the area of population administration, it has been effective, with several efforts to handle reports such as: (1) Clarification; (2) Investigation; (3) Recommendations; (4) Monitoring.


Carbon Trends ◽  
2021 ◽  
Vol 3 ◽  
pp. 100038
Author(s):  
Jian Gao ◽  
Xiujuan Chu ◽  
Xiaoyao Tan ◽  
Hongqi Sun ◽  
Zhen Yin ◽  
...  

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