Heterogeneous catalytic approaches in C-H activation reactions

Green Chem., 2016, Advance Article
DOI: 10.1039/C6GC00385K, Critical Review

Stefano Santoro, Sergei I. Kozhushkov, Lutz Ackermann, Luigi Vaccaro
This review summarizes the development of user-friendly, recyclable and easily separable heterogeneous catalysts for C-H activation during the last decade until December 2015.

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00385K?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

Despite the undisputed advances and progress in metal-catalyzed C–H functionalizations, this atom-economical approach had thus far largely been developed with the aid of various metal catalysts that were operative in a homogeneous fashion. 

While thereby major progress was accomplished, these catalytic systems featured notable disadvantages, such as low catalyst recyclability. This review summarizes the development of user-friendly, recyclable and easily separable heterogeneous catalysts for C–H activation.

This strategy was characterized by a remarkably broad substrate scope, considerable levels of chemo- and site-selectivities and proved applicable to C–C as well as C–heteroatom formation processes. 

Thus, recyclable catalysts were established for arylations, hydroarylations, alkenylations, acylations, nitrogenations, oxygenations, or halogenations, among others. The rapid recent progress in selective heterogeneous C–H functionalizations during the last decade until December 2015 is reviewed.

Heterogeneous catalytic approaches in C–H activation reactions

Stefano Santoro,^a   Sergei I. Kozhushkov,^b  Lutz Ackermann*^b and   Luigi Vaccaro*^a  

*

Corresponding authors

^a

Laboratory of Green Synthetic Organic Chemistry, Dipartimento di Chimica Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 8 – 06123 Perugia, Italy 
E-mail: luigi.vaccaro@unipg.it
Web: http://www.dcbb.unipg.it/greensoc

^b

Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany 
E-mail: Lutz.Ackermann@chemie.uni-goettingen.de
Web: http://www.ackermann.chemie.uni-goettingen.de

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00385K     

Laboratory of Green Synthetic Organic Chemistry, Dipartimento di Chimica Biologia e Biotecnologie, Università di Perugia, Via Elce di Sotto, 8 – 06123 Perugia, Italy 
E-mail: luigi.vaccaro@unipg.it
Web: http://www.dcbb.unipg.it/greensoc

Extra clips
 C-H Activation :: Wiley-VCH Hot Topics

www.wiley-vch.de

 
 The Yu Lab

www.scripps.edu

"Ligand-Enabled Triple C-H Activation Reactions: One-Pot Synthesis of Diverse 4-Aryl-2-quinolinones from Propionamides" Angew. Chem. Int. Ed. 2014, 53, ...

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N-Butylpyrrolidinone as a dipolar aprotic solvent for organic synthesis

Green Chem., 2016, Advance Article
DOI: 10.1039/C6GC00932H, Paper

James Sherwood, Helen L. Parker, Kristof Moonen, Thomas J. Farmer, Andrew J. Hunt
N-Butylpyrrolidinone (NBP) has been demonstrated as a suitable safer replacement solvent for N-Methylpyrrolidinone (NMP) in selected organic syntheses.

N-Butylpyrrolidinone as a dipolar aprotic solvent for organic synthesis

N-Butylpyrrolidinone as a dipolar aprotic solvent for organic synthesis

James Sherwood,^a   Helen L. Parker,^a   Kristof Moonen,^b  Thomas J. Farmer^a and   Andrew J. Hunt*^a  

*Corresponding authors

^aGreen Chemistry Centre of Excellence, Department of Chemistry, University of York, UK
E-mail: andrew.hunt@york.ac.uk

^bEastman Chemical Company, Pantserschipstraat 207 – B-9000, Gent, Belgium

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00932H

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00932H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

 

Dipolar aprotic solvents such as N-methylpyrrolidinone (or 1-methyl-2-pyrrolidone (NMP)) are under increasing pressure from environmental regulation. NMP is a known reproductive toxin and has been placed on the EU “Substances of Very High Concern” list. Accordingly there is an urgent need for non-toxic alternatives to the dipolar aprotic solvents. N-Butylpyrrolidinone, although structurally similar to NMP, is not mutagenic or reprotoxic, yet retains many of the characteristics of a dipolar aprotic solvent. This work introduces N-butylpyrrolidinone as a new solvent for cross-coupling reactions and other syntheses typically requiring a conventional dipolar aprotic solvent.

////N-Butylpyrrolidinone, dipolar aprotic solvent , organic synthesis

Dehydrogenative [2 + 2 + 1] Heteroannulation Using a Methyl Group as a One-Carbon Unit: Access to Pyrazolo[3,4-c]quinolines

 

Dehydrogenative [2 + 2 + 1] Heteroannulation Using a Methyl Group as a One-Carbon Unit: Access to Pyrazolo[3,4-c]quinolines

Guo-Bo Deng^†, Hai-Bing Li^†, Xu-Heng Yang^†, Ren-Jie Song^*†, Ming Hu^†, and Jin-Heng Li^*†‡

^† State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China

^‡ State Key Laboratory of Applied Organic Chemistry Lanzhou University, Lanzhou 730000, China

Org. Lett., Article ASAP

DOI: 10.1021/acs.orglett.6b00618

Publication Date (Web): April 28, 2016

Copyright © 2016 American Chemical Society

*E-mail: srj0731@hnu.edu.cn., *E-mail: jhli@hnu.edu.cn.

http://pubs.acs.org/doi/abs/10.1021/acs.orglett.6b00618

 A practical and straightforward access to pyrazolo[3,4-c]quinolines by molecular sieve mediated dehydrogenative [2 + 2 + 1] heteroannulation of N-(o-alkenylaryl)imines with aryldiazonium salts is described using a sp³-hybrid carbon atom as a one-carbon unit. The reaction enables the formation of three new chemical bonds, a C–C bond and two C–N bonds, in a single reaction and features simple operation and excellent functional group tolerance.

/////////Dehydrogenative [2 + 2 + 1] Heteroannulation,   Pyrazolo[3,4-c]quinolines

A continuous-flow process for the preparation of m-nitrothioanisole has been set up. The starting material m-nitroaniline was diazotized to give diazonium chloride, followed by azo-coupling with sodium thiomethoxide to give 1-(methylthio)-2-(3-nitrophenyl)diazene, then dediazoniated to gain m-nitrothioanisole in high yield. The continuous-flow process minimized accumulation of the energetic intermediate diazonium salt and has a better capacity for adapting large-scale production. A solvent was introduced in the azo-coupling section to create a biphasic flow system. Side products were inhibited eminently in this flow process.

Continuous-Flow Process for the Synthesis of m-Nitrothioanisole

Zhiqun Yu^†, Xiaoxuan Xie^†, Hei Dong^†, Jiming Liu^‡, and Weike Su^*†‡

^† National Engineering Research Center for Process Development of Active Pharmaceutical Ingredients, Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, P. R. China

^‡ Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P. R. China

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.6b00023

Publication Date (Web): March 24, 2016

Copyright © 2016 American Chemical Society

*Tel.: (+86)57188320899. E-mail: pharmlab@zjut.edu.cn.

http://pubs.acs.org/doi/abs/10.1021/acs.oprd.6b00023
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