scholarly journals Nickel Boride Catalyzed Reductions of Nitro Compounds and Azides: Nanocellulose-supported Catalysts in Tandem Reactions

Synthesis ◽  
2021 ◽  
Author(s):  
Giampiero Proietti ◽  
Kaniraj Jeya Prathap ◽  
Xinchen Ye ◽  
Richard T. Olsson ◽  
Peter Dinér
Keyword(s):  
Aqueous Solution ◽  
Supported Catalysts ◽  
Nitro Compounds ◽  
Catalyst Loading ◽  
Nickel Salt ◽  
One Pot ◽  
Nickel Boride ◽  
Wide Range ◽  
Stabilizing Effect

Nickel boride catalyst prepared in situ from NiCl2 and sodium borohydride allowed, in the presence of an aqueous solution of TEMPO-oxidized nanocellulose (0.01 wt%), the reduction of a wide range of nitroarenes and aliphatic nitro compounds. Here we describe how the modified nanocellulose has a stabilizing effect on the catalyst that enables low loading of the nickel salt pre-catalyst. Ni-B prepared in situ from a methanolic solution was also used to develop a greener and facile reduction of azides, offering a substantially lowered catalyst loading with respect to reported methods in the literature. Both aromatic and aliphatic azides were reduced and the protocol is compatible with a one-pot Boc-protection of the obtained amine yielding the corresponding carbamates. Finally, bacterial crystalline nanocellulose was chosen as a support for the Ni-B catalyst to allow an easy recovery step of the catalyst and its recyclability for new reduction cycles.

Indium Bromide-catalyzed Unprecedented Hydrogenolysis: A Novel One-Pot Synthesis of Per-O-Acetylated β-carboxymethyl O and S-glycosides

2020 ◽  
Vol 24 (8) ◽  
pp. 900-908
Author(s):  
Ram Naresh Yadav ◽  
Amrendra K Singh ◽  
Bimal Banik
Keyword(s):  
Asymmetric Synthesis ◽  
Chiral Auxiliary ◽  
Bioactive Molecules ◽  
One Pot ◽  
Enantiomerically Pure ◽  
Stereoselective Glycosylation ◽  
One Pot Synthesis ◽  
Wide Range

Numerous O (oxa)- and S (thia)-glycosyl esters and their analogous glycosyl acids have been accomplished through stereoselective glycosylation of various peracetylated bromo sugar with benzyl glycolate using InBr3 as a glycosyl promotor followed by in situ hydrogenolysis of resulting glycosyl ester. A tandem glycosylating and hydrogenolytic activity of InBr3 has been successfully investigated in a one-pot procedure. The resulting synthetically valuable and virtually unexplored class of β-CMGL (glycosyl acids) could serve as an excellent potential chiral auxiliary in the asymmetric synthesis of a wide range of enantiomerically pure medicinally prevalent β-lactams and other bioactive molecules of diverse medicinal interest.

Molybdenum-Mediated One-Pot Synthesis of Pyrazoles from Isoxazoles

Synthesis ◽  
2019 ◽  
Vol 51 (20) ◽  
pp. 3796-3804 ◽  
Author(s):  
Marine Rey ◽  
Stéphane Beaumont
Keyword(s):  
Bond Cleavage ◽  
Direct Synthesis ◽  
Molybdenum Complex ◽  
One Pot ◽  
One Pot Synthesis ◽  
Wide Range ◽  
Hydrolysis Of ◽  
Substituted Pyrazoles

A one-pot approach for the direct synthesis of substituted pyrazoles from isoxazoles is reported. The process involves isoxazole N–O bond cleavage mediated by a molybdenum complex, in situ hydrolysis of the resulting β-amino enone to the corresponding 1,3-diketone, followed by pyrazole formation in the presence of hydrazine or substituted hydrazine. Good to excellent yields and regioselectivities are obtained with nonsymmetric isoxazoles. By using readily available starting materials, a wide range of substituted pyrazoles may be synthesized by this method.

One-pot synthesis of nitrones from nitro compounds by in situ trapping of arylhydroxylamines

2017 ◽  
Vol 148 (6) ◽  
pp. 1101-1107 ◽  
Author(s):  
Foad Kazemi ◽  
Moosa Ramdar ◽  
Bahram Tavana ◽  
Jamal Davarpanah
Keyword(s):  
Nitro Compounds ◽  
One Pot ◽  
One Pot Synthesis

Direct growth of layered intercalation compounds via single step one-pot in situ synthesis

2015 ◽  
Vol 51 (57) ◽  
pp. 11398-11400 ◽  
Author(s):  
Jingfang Yu ◽  
Lichen Xiang ◽  
Benjamin R. Martin ◽  
Abraham Clearfield ◽  
Luyi Sun
Keyword(s):  
Synthesis Method ◽  
Layered Materials ◽  
Single Step ◽  
In Situ Synthesis ◽  
Intercalation Compounds ◽  
One Pot ◽  
Wide Range ◽  
Direct Growth

A single step one-pot in situ synthesis method was developed to directly grow layered intercalation compounds. This methodology is expected to be applicable to a wide range of layered materials.

Fe3O4@chitosan nanoparticles: a valuable heterogeneous nanocatalyst for the synthesis of 2,4,5-trisubstituted imidazoles

RSC Advances ◽  
2014 ◽  
Vol 4 (40) ◽  
pp. 20932-20939 ◽  
Author(s):  
Zohre Zarnegar ◽  
Javad Safari
Keyword(s):  
Aqueous Solution ◽  
Catalytic Activity ◽  
Ammonium Acetate ◽  
Chitosan Nanoparticles ◽  
One Pot ◽  
Heterogeneous Nanocatalyst ◽  
Aryl Aldehydes ◽  
One Pot Condensation ◽  
Co Precipitation

Chitosan-coated Fe3O4 nanoparticles (Fe3O4@CS) were prepared simply through in situ co-precipitation of Fe2+ and Fe3+ ions via NH4OH in an aqueous solution of chitosan and their catalytic activity was investigated in the synthesis of 2,4,5-trisubstituted imidazoles by a one-pot condensation of benzil derivatives, aryl aldehydes and ammonium acetate in EtOH.

Synthesis of bis-spiropiperidines using nano-CuFe2O4@chitosan as a robust and retrievable heterogeneous catalyst

2017 ◽  
Vol 41 (7) ◽  
pp. 416-419 ◽  
Author(s):  
Javad Safaei-Ghomi ◽  
Mohammad Rasool Lashkari ◽  
Hossein Shahbazi-Alavi
Keyword(s):  
Heterogeneous Catalyst ◽  
Aromatic Amine ◽  
Room Temperature ◽  
Barbituric Acid ◽  
Catalyst Loading ◽  
Reaction Conditions ◽  
One Pot ◽  
Wide Range ◽  
One Pot Condensation

An efficient pseudo six-component synthesis of bis-spiropiperidines is described by one-pot condensation of formaldehyde, aromatic amine and dimedone or N,N-dimethyl-barbituric acid using nano-CuFe2O4@chitosan at room temperature. This method provides several advantages including mild reaction conditions, applicability to wide range of substrates, reusability of the catalyst and little catalyst loading.

Chitosan-attached nano-Fe3O4 as a superior and retrievable heterogeneous catalyst for the synthesis of benzopyranophenazines using chitosan-attached nano-Fe3O4

2019 ◽  
Vol 74 (10) ◽  
pp. 733-738
Author(s):  
Javad Safaei-Ghomi ◽  
Maryam Tavazo ◽  
Hossein Shahbazi-Alavi
Keyword(s):  
Solid Acid Catalyst ◽  
Reaction Times ◽  
Acid Catalyst ◽  
Catalyst Loading ◽  
High Catalytic Activity ◽  
One Pot ◽  
X Ray ◽  
Wide Range ◽  
Nano Fe3o4 ◽  
Low Catalyst Loading

AbstractA simple and rapid method for the preparation of benzopyranophenazines is presented, involving a one-pot four-component reaction of hydroxynaphthoquinone, o-phenylenediamine, benzaldehydes, and malononitrile with nano-Fe3O4@chitosan as an efficient heterogeneous solid acid catalyst under reflux conditions in ethanol. The catalyst is characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), magnetic susceptibility measurements, energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared (FT-IR) spectroscopy. Atom economy, high catalytic activity, a wide range of products, excellent yields in short reaction times, and low catalyst loading are some of the important features of this method.

scholarly journals Cross-Linked Self-Assembling Peptides and Their Post-Assembly Functionalization via One-Pot and In Situ Gelation System

2020 ◽  
Vol 21 (12) ◽  
pp. 4261
Author(s):  
Raffaele Pugliese ◽  
Fabrizio Gelain
Keyword(s):  
Mechanical Properties ◽  
Self Assembly ◽  
Self Healing ◽  
One Pot ◽  
Self Assembling ◽  
In Situ Gelation ◽  
Wide Range ◽  
Peptide Hydrogels ◽  
Peptide Hydrogel

Supramolecular nanostructures formed through peptide self-assembly can have a wide range of applications in the biomedical landscape. However, they often lose biomechanical properties at low mechanical stress due to the non-covalent interactions working in the self-assembling process. Herein, we report the design of cross-linked self-assembling peptide hydrogels using a one-pot in situ gelation system, based on 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide/N-hydroxysulfosuccinimide (EDC/sulfo–NHS) coupling, to tune its biomechanics. EDC/sulfo–NHS coupling led to limited changes in storage modulus (from 0.9 to 2 kPa), but it significantly increased both the strain (from 6% to 60%) and failure stress (from 19 to 35 Pa) of peptide hydrogel without impairing the spontaneous formation of β-sheet-containing nano-filaments. Furthermore, EDC/sulfo–NHS cross-linking bestowed self-healing and thixotropic properties to the peptide hydrogel. Lastly, we demonstrated that this strategy can be used to incorporate bioactive functional motifs after self-assembly on pre-formed nanostructures by functionalizing an Ac-LDLKLDLKLDLK-CONH2 (LDLK12) self-assembling peptide with the phage display-derived KLPGWSG peptide involved in the modulation of neural stem cell proliferation and differentiation. The incorporation of a functional motif did not alter the peptide’s secondary structure and its mechanical properties. The work reported here offers new tools to both fine tune the mechanical properties of and tailor the biomimetic properties of self-assembling peptide hydrogels while retaining their nanostructures, which is useful for tissue engineering and regenerative medicine applications.

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