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1.
Sci Rep ; 8(1): 2024, 2018 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-29386553

RESUMEN

Goethite with protuberant lychee morphology has been synthesized that accomplishes C-H activation of N-methylanilines to generate α-aminonitriles; the catalyst takes oxygen from air and uses it as a co-oxidant in the process.

2.
Catal Today ; 309: 248-252, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31595104

RESUMEN

Graphitic carbon nitride supported palladium nanoparticles, Pd@g-C3N4, have been synthesized and utilized for the direct oxidative esterification of alcohols using atmospheric oxygen as a co-oxidant via photocatalytic C-H activation.

3.
Sci Rep ; 7(1): 655, 2017 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-28381827

RESUMEN

A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydrating agent or requirement for azeotropic distillation.

4.
Tetrahedron ; 73(38): 5577-5580, 2017 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-30294048

RESUMEN

The titanium cluster with the reduced band gap has been synthesized having the palladium nanoparticles over the surface, which not only binds to the atmospheric oxygen but also catalyzes the oxidation of alcohols under visible light.

5.
Green Chem ; 19(1): 164-168, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30319311

RESUMEN

An organic sulfonated graphitic carbon nitride is synthesized and its application has been demonstrated in the conversion of carbohydrates into furanics and related value-added products. The most important feature of the material is the stability and acidity, which could be utilized at elevated temperatures for cleaving carbohydrates and converting them into biologically important scaffolds and platform chemicals.

6.
Sci Rep ; 6: 39387, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27991593

RESUMEN

Sulfonation of graphitic carbon nitride (g-CN) affords a polar and strongly acidic catalyst, Sg-CN, which displays unprecedented reactivity and selectivity in biodiesel synthesis and esterification reactions at room temperature.

7.
Sci Total Environ ; 472: 316-23, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-24295749

RESUMEN

The recent surge in consumer products and applications using metallic nanoparticles has increased the possibility of human or ecosystem exposure due to unintentional release into the environment. To protect consumer health and the environment, there is an urgent need to develop tools that can characterize and quantify these materials at low concentrations and in complex matrices. In this study, magnetic nanoparticles coated with either dopamine or glutathione were used to develop a new, simple and reliable method for the separation/pre-concentration of trace amounts of silver nanoparticles followed by their quantification using inductively coupled plasma mass spectrometry (ICP-MS). The structurally modified magnetic particles were able to capture trace amounts of silver nanoparticles (~2 ppb) and concentrate (up to 250 times) the particles for analysis with ICP-MS. Under laboratory conditions, recovery of silver nanoparticles was >99%. More importantly, the magnetic particles selectively captured silver nanoparticles in a mixture containing both nano-particulate and ionic silver. This unique feature addresses the challenges of separation and quantification of silver nanoparticles in addition to the total silver in environmental samples. Spiking experiments showed recoveries higher than 97% for tap water and both fresh and saline surface water.


Asunto(s)
Nanopartículas del Metal/química , Modelos Químicos , Plata/química , Fenómenos Magnéticos , Nanopartículas del Metal/análisis , Tamaño de la Partícula , Plata/análisis
8.
Chem Commun (Camb) ; 49(8): 752-70, 2013 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-23212208

RESUMEN

The use of magnetic nanoparticles (MNPs) as a catalyst support in organic synthesis is summarized. The recovery of expensive catalysts after catalytic reaction and reusing them without losing their activity is an essential feature in the sustainable process development. The aim of this article is to highlight the progress in the synthesis and catalytic applications of magnetic catalysts in organic synthesis. The heterogenization of the catalyst using magnetic nanoparticles allows it to be recovered and reused using an external magnet.

9.
Chem Commun (Camb) ; 48(71): 8889-91, 2012 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-22814637

RESUMEN

Unnatural α-amino acids containing dithiocarbamate side chains were synthesized by a one-pot reaction of in situ generated dithiocarbamate anions with sulfamidates. A wide range of these anions participated in the highly regio- and stereo-selective ring opening of sulfamidates to produce the corresponding dithiocarbamate pendant α-amino acids in high yields.


Asunto(s)
Aminoácidos/química , Tiocarbamatos/química , Aminoácidos/síntesis química , Aniones/química , Estereoisomerismo , Ácidos Sulfónicos/química
10.
Chem Commun (Camb) ; 48(47): 5853-5, 2012 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-22572790

RESUMEN

Synthesis of triazole based unnatural amino acids and ß-amino triazoles has been described via a stereo and regioselective one-pot multi-component reaction of sulfamidates, sodium azide, and alkynes under MW conditions. The developed method is applicable to a broad substrate scope and has significant potential for the synthesis of unnatural amino acids with a triazole side chain.


Asunto(s)
Aminoácidos/síntesis química , Triazoles/síntesis química , Alquinos/química , Azida Sódica/química , Estereoisomerismo , Ácidos Sulfónicos/química , Triazoles/química
11.
Chem Commun (Camb) ; 48(50): 6220-2, 2012 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-22592337

RESUMEN

One-pot synthesis of ruthenium hydroxide nanoparticles on magnetic silica is described which involves the in situ generation of magnetic silica (Fe(3)O(4)@SiO(2)) and ruthenium hydroxide immobilization; the hydration of nitriles occurs in high yield and excellent selectivity using this catalyst which proceeds exclusively in aqueous medium under neutral conditions.


Asunto(s)
Amidas/síntesis química , Hidróxidos/química , Nanopartículas/química , Nitrilos/química , Rutenio/química , Dióxido de Silicio/química , Amidas/química , Magnetismo , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie , Agua/química
12.
Chem Commun (Camb) ; 48(20): 2582-4, 2012 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-22293995

RESUMEN

Diaryl sulfides were synthesized using a magnetically recoverable heterogeneous Cu catalyst via one-pot multi component reaction using MW irradiation; the use of isopropanol as a benign reaction medium, easy recovery of the catalyst using an external magnet, efficient recycling, and the high stability of the catalyst render the protocol economic and sustainable.


Asunto(s)
Clorobencenos/química , Cobre/química , Dopamina/química , Nanopartículas de Magnetita/química , Fenoles/química , Compuestos de Sulfhidrilo/química , 2-Propanol/química , Catálisis , Microscopía Electrónica de Transmisión , Estructura Molecular
13.
Chem Soc Rev ; 41(4): 1559-84, 2012 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-22076552

RESUMEN

Microwave, ultrasound, sunlight and mechanochemical mixing can be used to augment conventional laboratory techniques. By applying these alternative means of activation, a number of chemical transformations have been achieved thereby improving many existing protocols with superior results when compared to reactions performed under traditional conditions. The purpose of this critical review is to highlight the advances in this general area by presenting such newer applications in organic synthesis (175 references).

14.
Eur J Med Chem ; 46(3): 835-44, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21277051

RESUMEN

Three series of novel glitazones were designed and prepared by using appropriate synthetic schemes to incorporate glycine, aromatic and alicyclic amines via two carbon linker. Compounds were synthesized both under conventional and microwave methods. Nineteen out of twenty four synthesized compounds were evaluated for their in vitro glucose uptake activity using isolated rat hemi-diaphragm. Compounds, 6, 9a, 13a, 13b, 13c, 13f and 13h exhibited significant glucose uptake activity. Illustration about their synthesis and in vitro glucose uptake activity is described along with the structure-activity relationships.


Asunto(s)
Glucosa/metabolismo , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Tiazolidinedionas/química , Tiazolidinedionas/farmacología , Aminas/síntesis química , Aminas/química , Animales , Diafragma/efectos de los fármacos , Diafragma/metabolismo , Femenino , Glicina/síntesis química , Glicina/química , Hipoglucemiantes/síntesis química , Masculino , Modelos Moleculares , Ratas , Ratas Wistar , Relación Estructura-Actividad , Tiazolidinedionas/síntesis química
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