Pd/Cu-free Heck and Sonogashira cross-coupling reaction by Co nanoparticles immobilized on magnetic chitosan as reusable catalyst

 

Pd/Cu-free Heck and Sonogashira cross-coupling reaction by Co nanoparticles immobilized on magnetic chitosan as reusable catalyst

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03377F, Paper
Abdol R. Hajipour, Fatemeh Rezaei, Zahra Khorsandi
Chitosan (CS) is a porous, self-standing, nanofibrillar microsphere that can be used as a metal carrier. Amino groups on CS enable to modulate cobalt coordination using a safe organic ligand (methyl salicylate).

Pd/Cu-free Heck and Sonogashira cross-coupling reaction by Co nanoparticles immobilized on magnetic chitosan as reusable catalyst

aDepartment of Chemistry, Isfahan University of Technology, Isfahan 84156, Iran
E-mail: haji@cc.iut.ac.ir
Fax: +98 311 391 2350
Tel: +98 311 391 3262
bDepartment of Neuroscience, University of Wisconsin, Medical School, Madison, USA
Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03377F

Department of Chemistry
Office : College of Chemistry, Isfahan University of Technology, Isfahan 84156, IR IranPhone : +98 311 391xxxxFax : +98 311 391xxxxWeb Site : Prof. Abdolreza Hajipour
EDUCATION:
1970-1974               High School, Shahpour high school, Kazerun, IR, Iran
1975-1979               B.S., Chemistry, Department of Chemistry, Isfahan University, Isfahan, I.R. Iran
1981-1983               M.S., Organic Chemistry, Synthesis, Shiraz University, Shiraz, I.R. Iran
Thesis Title: “Synthesis of 2,6,7,11-Tetraphenyl Isobenzofuran B Cyclobutadiene”
Advisor: Professor Habib Firouzabadi
1990-1994               Ph.D., Organic Chemistry, Wollongong University, Australia
Dissertation Title: “Asymmetric Synthesis of Chiral Amines and Benzazepine Alkaloids from Chiral Sulfoxides”
Advisor: Professor Stephen G. Pyne

POSITIONS:
09/94-11/98            Assistant Professor, Isfahan University of Technology
12/98-02/03            Associate Professor, Isfahan University of Technology
03/03-present        Professor, Isfahan University of Technology
02/01-03/02            Visiting Scientist, University of Wisconsin Medical School, Madison, WI
04/02-09/02            Associate Researcher, University of Wisconsin Medical School, Madison, WI
10/02-1/05              Associate Scientist, University of Wisconsin Medical School, Madison, WI
1/04 to present      Senior Scientist, University of Wisconsin Medical School, Madison, WI
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Chitosan (CS) is a porous, self-standing, nanofibrillar microsphere that can be used as a metal carrier. Amino groups on CS enable to modulate cobalt coordination using a safe organic ligand (methyl salicylate). This catalyst efficiently promotes Heck cross-coupling of a large library of functional substrates under mild and sustainable conditions (polyethylene glycol as solvent at 80 °C in a short time (1 h)). The cobalt complex was also used as a heterogeneous, efficient, inexpensive, and green catalyst for Sonogashira cross-coupling reactions. The reactions of various aryl halides and phenylacetylene provided the corresponding products in moderate to good yields. More importantly, this phosphine, copper, and palladium-free catalyst was stable under the reaction conditions and could be easily reused using an external magnet for at least five successive runs without a discernible decrease in its catalytic activity.
Reaction yields were analyzed by gas chromatography (GC, BEIFEN-3420, detector type: FID, TCD equipped with Nukol™ capillary GC column, size × I.D. 30 m × 0.25 mm, df 0.25 μm). 2,3-Dimethylnaphthalene as was used as internal standard. The gas flow rate of 2 mL min-1; and oven temperature at 80 oC for 15 min and then increased to 170 oC.
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General procedure for catalyst preparation The magnetic nanoparticles (MNPs) were prepared according to the method reported in literature64 based on the precipitation of magnetite nanoparticles from a mixture of iron(III) chloride and iron(II) sulfate by ammonia (25% solution in water). Subsequently, in a round-bottom flask equipped with a mechanical stirrer and condenser, a mixture of magnetic nanoparticles and sodium sulfate (20%, w/v) was added to a solution of chitosan (1%, w/v) in acetic acid (2%, w/v) under stirring. Stirring was continued for 1 h to obtain the aqueous suspension of MNPs/CS. Then, the magnetic nanoparticles were separated from the reaction mixture by an external permanent magnet, washed with ethanol and methanol several times, and dried under vacuum at 70 °C. For the preparation of supported methyl salicylate ligands, a solution of ethanol suspension of MNPs/CS (1.5 g per 10 mL) was added to methyl salicylate (6.5 mmol), and the mixture was stirred at 60 °C for 24 h. The final Co-MS@MNPs/CS was obtained as a brown solid by the addition of CoCl2·6H2O (4.2 mmol) dissolved in 10 mL of ethanol to disperse the mixture of MNPs/CS-MS (1.01 g) in ethanol (5 mL) and stirred at 60 °C for 18 h. The resulting complex was collected by an external permanent magnet, washed with ethanol (3 × 10 mL) to remove the unreacted materials, and finally dried in air (89% yield based on the amount of Co in the catalyst determined by ICP).
General procedure for the Heck reaction In a round-bottom flask equipped with a mechanical stirrer, a mixture of K3PO4 (4 eq.), olefin (1.1 mmol), and aryl halide (1 mmol) in PEG (3 mL) was added to 5 mg of catalyst (1.1 mol% of Co) and the flask was equipped with a condenser for refluxing. The abovementioned mixture was heated at 80 °C in an oil bath. The progress of the reaction was monitored by TLC (hexane/EtOAc, 80 : 20) and gas chromatography (GC). After the completion of the reaction, the mixture was diluted with dichloromethane and water. The organic layer was washed with brine, dried over anhydrous MgSO4, and concentrated under reduced pressure. The residue was purified by column chromatography. The products were characterized by comparing their physical properties, such as m.p., IR, 1 H, and 13C NMR spectra, with those reported in literature
General procedure for Sonogashira reaction In a round-bottom flask equipped with a mechanical stirrer, phenyl acetylene (1.2 mmol), aryl halide (1.0 mmol), catalyst (10 mg), and KOH (2 eq.) in DMSO (3 mL) were stirred under an air atmosphere at 140 °C. The progress of the reaction was monitored using TLC and GC. After the completion of the reaction, the mixture was diluted with dichloromethane and water. The organic layer was washed with brine, dried over anhydrous MgSO4, and concentrated under reduced pressure. The product was isolated by column chromatography to afford the corresponding products in 55–80% yields. The products were characterized by comparing their physical properties, such as m.p, IR, 1 H, and 13C NMR spectra with those reported in literature.
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Endogenous water-triggered and ultrasound accelerated synthesis of 1,5-disubstituted tetrazoles via a solvent and catalyst-free Ugi-azide reaction

 

Endogenous water-triggered and ultrasound accelerated synthesis of 1,5-disubstituted tetrazoles via a solvent and catalyst-free Ugi-azide reaction

Green Chem., 2017, Advance Article
DOI: 10.1039/C6GC03324E, Communication
Shrikant G. Pharande, Alma Rosa Corrales Escobosa, Rocio Gamez-Montano
An ultrasound accelerated, environmentally benign Ugi-azide based method was developed for the synthesis of 1,5-disubstituted tetrazoles under solvent and catalyst-free conditions.

Endogenous water-triggered and ultrasound accelerated synthesis of 1,5-disubstituted tetrazoles via a solvent and catalyst-free Ugi-azide reaction

 *Corresponding authors
aDepartamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, Guanajuato, México
E-mail: rociogm@ugto.mx
Green Chem., 2017, Advance Article

DOI: 10.1039/C6GC03324E,  http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C6GC03324E?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

A novel, sustainable, endogenous water-triggered, environmentally friendly, high substrate scope, efficient, solvent-free and catalyst-free Ugi-azide based method for the synthesis of 1,5-disubstituted tetrazoles is described.
Shrikant Pharande

Shrikant Pharande

Doctoral student

Research experience

  • Apr 2014–Jun 2014, Research chemist
    TCG Lifesciences · pune
  • Mar 2012–Dec 2013, project assistant
    CSIR – National Chemical Laboratory, Pune · Organic Chemistry Division (NCL)
N-((1-(tert-butyl)-1H-tetrazol-5-yl)(4-chlorophenyl)methyl)aniline (4a)
Based on GP, 100 mg 4-Chlorobenzaldehyde (0.71 mmol), 0.065 cm3 aniline (0.71 mmol), 0.080 cm3 ter. Butyl isocyanide (0.71 mmol), and 0.093 cm3 TMS-azide (0.71 mmol) were reacted together to afford 237 mg (97%) as a white solid.
Melting range 144-145oC,
Rf = 0.45 (Hexane-AcOEt = 7/3 V/V),
1H NMR (500 MHz, CDCl3) δ 7.34 – 7.29 (m, 4H), 7.18 – 7.13 (m, 2H), 6.79 – 6.75 (m, 1H), 6.65 (d, J = 7.6 Hz, 2H), 6.11 (d, J = 6.2 Hz, 1H), 4.78 (d, J = 5.6 Hz, 1H), 1.71 (s, 9H);
13C NMR (126 MHz, CDCl3) δ 155.03, 145.54, 136.81, 134.71, 129.62, 129.43, 129.19, 119.64, 114.42, 61.95, 53.93, 30.29;
FT-IR (ATR) νmax/cm-1 3330.5, 3052.5, 2940.9, 1603.6, 1284.1;
HRMS (ESI+): m/z calcd. for C18H20ClN5 + 342.1480, found 342.1474
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Activated nanostructured bimetallic catalysts for C-C coupling reactions: recent progress

Catal. Sci. Technol., 2016, 6,3341-3361
DOI: 10.1039/C5CY02225H, Minireview
Rohit Kumar Rai, Deepika Tyagi, Kavita Gupta, Sanjay Kumar Singh
This minireview highlights the recent progress made in the last decade towards the development of activated bimetallic alloy nanoparticle catalysts for C-C coupling reactions, including asymmetric C-C bond coupling reactions.
Minireview

Activated nanostructured bimetallic catalysts for C–C coupling reactions: recent progress

*Corresponding authors
aDiscipline of Chemistry, Indian Institute of Technology (IIT) Indore, Simrol, Indore, 452 020 India
bCentre for Material Science and Engineering, Indian Institute of Technology (IIT) Indore, Simrol, Indore, 452 020 India
E-mail: sksingh@iiti.ac.in
Fax: +91 731 2438 933
Catal. Sci. Technol., 2016,6, 3341-3361

DOI: 10.1039/C5CY02225H

Catalysts based on bimetallic nanoparticles have received tremendous scientific and industrial attention and are established as an important class of active catalysts. These catalysts displayed improved catalytic activities compared to their monometallic counterparts for several reactions, which is attributed to their highly modified surface structures (electronic and geometrical) due to the synergic cooperation between the two metals of the bimetallic nanoparticle catalyst. Moreover, such synergic interactions are more prominent in alloy nanoparticle catalysts, where the probability of metal-to-metal interactions is higher in comparison with other systems (such as core–shell nanoparticles). This minireview highlights the recent progress made in the last decade towards the development of activated bimetallic alloy nanoparticle catalysts for C–C coupling reactions, including asymmetric C–C bond coupling reactions. Herein, the influence of the modified electronic structures of the newly formed bimetallic alloy nanoparticle catalysts on their activated catalytic performance is also discussed extensively.
Dr. Sanjay Kumar Singh
Assistant Professor
Chemistry
Organometallics and Nanotech Catalysis Group
Discipline of Chemistry, School of Basic Sciences
Dr. Sanjay Kumar Singh
Assistant Professor
Chemistry
sksingh[at]iiti.ac.in
Mr. Rohit Rai
Ph.D. Student (CSIR-SRF), Since Jan. 2013
He obtained his Masters degree in Organic Chemistry from BHU Varanasi in the year 2012. He is presently engaged in the development of nanoparticle based heterogeneous catalysts for important organic reactions.
rohitrai47[at]gmail.com; phd12123108[at]iiti.ac.in

 

Ms. Deepika Tyagi
Ph.D. Student (UGC-SRF), Since Jan. 2013
She obtained her Masters degree in Organic Chemistry from C.C.S. Meerut University in the year 2011. She is presently engaged in the development of homogeneous catalysts based on organometallic and coordination complexes for important organic reactions.
tyagi.deepika30[at]gmail.com; phd12123112[at]iiti.ac.in
Deepika Tyagi Deepika Tyagi
Ph.D. Scholar
Dr. Sanjay Research Group
M-Block, IIT Indore
Email: phd12123112[at]iiti.ac.in
Research Topic: Development of homogeneous catalysts based on metal complexes for important organic reactions
Ms. Kavita Gupta
Ph.D. Student (CSIR-SRF), Since Jul., 2013
She obtained her Masters degree in Organic Chemistry from Dr. B.R.A. University, Agra in the year 2010. She is presently engaged in the development of catalytic systems for the conversion of bioderived molecules to bio-fuel components and other important products.
phd1301131005[at]iiti.ac.in
ALL AUTHORS
//////Activated nanostructured,  bimetallic catalysts,  C-C coupling reactions,  recent progress

Mechanisms and reactivity differences of proline-mediated catalysis in water and organic solvents

Catal. Sci. Technol., 2016, 6,3378-3385
DOI: 10.1039/C6CY00033A, Paper
Gang Yang, Lijun Zhou
Several key issues regarding the mechanisms of proline catalysis are unravelled by first-principles calculations that can guide future catalyst design.

Mechanisms and reactivity differences of proline-mediated catalysis in water and organic solvents

Gang Yang*a and   Lijun Zhoua  
*Corresponding authors
aCollege of Resource and Environment & Chongqing Key Laboratory of Soil Multi-scale Interfacial Process, Southwest University, Chongqing, PR China
E-mail: theobiochem@gmail.com
Fax: +86 023 68250444
Tel: +86 023 68251545
Catal. Sci. Technol., 2016,6, 3378-3385

DOI: 10.1039/C6CY00033A

Proline is an efficient and versatile catalyst for organic reactions while a number of issues remain controversial. Here, ab initio and density functional calculations were used to unravel a few key issues of catalytic mechanisms in water and organic solvents. Zwitterionic proline that predominates in water and DMSO is assumed to be the active conformation for catalysis, and reactivity differences in two solvents are revealed. Meanwhile, an abundance of experimental observations can be finely interpreted by the present computational results, including those seemingly contradictory. Although bearing lower activation barriers than that in DMSO, the production of enamines and further aldol products in water will be blocked at an early stage (J. Am. Chem. Soc., 2006, 128, 734) because the reaction in water is significantly driven towards acetyl formation that is kinetically and thermodynamically preferred. Due to significant promotion of the rate-determining proton transfer step, aldol reactions in organic solvents can be obviously initiated by the addition of some water (Angew. Chem., Int. Ed., 2004, 43, 1983). In order to show catalytic effects in water (an obviously environmentally benign solvent), proline has to be structurally modified so that canonical structures can be the principal (or sole) conformations, which is in line with the analyses of all proline-based catalysts available in water (e.g., J. Am. Chem. Soc., 2006, 128, 734, Catal. Commun., 2012, 26, 6). Thus, the present results provide insightful clues to mechanisms of proline-mediated catalysis as well as future design of more efficient catalysts.
//////Mechanisms,  reactivity,  differences,  proline-mediated catalysis, water ,  organic solvents

Intensified biocatalytic production of enantiomerically pure halophenylalanines from acrylic acids using ammonium carbamate as the ammonia source

Catal. Sci. Technol., 2016, Advance Article
DOI: 10.1039/C6CY00855K, Communication
Nicholas J. Weise, Syed T. Ahmed, Fabio Parmeggiani, Elina Siirola, Ahir Pushpanath, Ursula Schell, Nicholas J. Turner
An industrial-scale method employing a phenylalanine ammonia lyase enzyme

Intensified biocatalytic production of enantiomerically pure halophenylalanines from acrylic acids using ammonium carbamate as the ammonia source

*Corresponding authors
aManchester Institute of Biotechnology & School of Chemistry, University of Manchester, 131 Princess Street, Manchester, UK
E-mail: nicholas.turner@manchester.ac.uk
bJohnson Matthey Catalysts and Chiral Technologies, 28 Cambridge Science Park, Milton Road, Cambridge, UK
Catal. Sci. Technol., 2016, Advance Article

DOI: 10.1039/C6CY00855K

SEE

An intensified, industrially-relevant strategy for the production of enantiopure halophenylalanines has been developed using the novel combination of a cyanobacterial phenylalanine ammonia lyase (PAL) and ammonium carbamate reaction buffer. The process boasts STYs up to >200 g L−1 d−1, ees ≥ 98% and simplified catalyst/reaction buffer preparation and work up.

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///////Intensified,  biocatalytic production, enantiomerically pure,  halophenylalanines,  acrylic acids,  ammonium carbamate, ammonia source

Plastically deformed Cu-based alloys as high-performance catalysts for the reduction of 4-nitrophenol

Catal. Sci. Technol., 2016, Advance Article
DOI: 10.1039/C6CY00734A, Paper
Eredzhep Menumerov, Kyle D. Gilroy, Maryam Hajfathalian, Colin J. Murphy, Erica R. McKenzie, Robert A. Hughes, Svetlana Neretina
Plastically deformed mesoscopic structures exposed to an etching procedure are demonstrated as highly catalytic in the reduction of 4-nitrophenol.

Plastically deformed Cu-based alloys as high-performance catalysts for the reduction of 4-nitrophenol

Plastically deformed Cu-based alloys as high-performance catalysts for the reduction of 4-nitrophenol

The severe plastic deformation of metals leads to the formation of nanotextured surfaces as well as the retention of significant strain energy, characteristics which are known to promote catalytic activity. Here, we demonstrate plastically deformed surfaces of copper and copper-based alloys as being highly catalytic using the well-studied model catalytic reaction which reduces 4-nitrophenol to 4-aminophenol by borohydride. Among the materials studied, the most catalytically active is formed in a two-step process where metal chips are mechanically sheared from a Cu–Sn alloy containing precipitates and then exposed to an etchant which removes the precipitates from the exposed surface. The so-formed structures exhibit exceedingly high catalytic activity and set new benchmarks when incorporated into a fixed-bed reactor. The formation of catalytically active sites is shown to be strongly dependent on the presence of the precipitates during the deformation process, achieving an order of magnitude increase in the reaction rate constant when compared to similarly formed Cu–Sn catalysts lacking these precipitates. The work, therefore, demonstrates a new approach for generating catalytically active sites which may be applicable to other alloy combinations.

 

////Plastically deformed, Cu-based alloys,  high-performance catalysts,  reduction, 4-nitrophenol