18 research outputs found
Sustainable multicomponent indole synthesis with broad scope
The most preferred heterocyclic indole core was de novo assembled by an innovative 2-step reaction from inexpensive and broadly available anilines, glyoxal dimethyl acetal, formic acid and isocyanides involving an Ugi multicomponent reaction followed by an acid induced cyclization. As opposed to many other indoles syntheses, our method delivers under mild and benign conditions using ethanol as solvent and no metal catalyst. The scope of the reactions was scouted and 20 derivatives are described
Fluorene-Based Multicomponent Reactions
Fluorene and fluorenone are privileged structures with extensive utility in both materials science and drug discovery. Here, we describe syntheses of those moieties through isocyanide-based multicomponent reactions (IMCRs) and the incorporation of the products in diverse and complex derivatives that can be further utilized. We performed six different IMCRs, based on the dual functionality of 9-isocyano-9H-fluorene, and we describe 23 unprecedented adducts
Proton conductivity and luminiscence properties of lanthanide aminotriphosphonates
Metal phosphonates are multifunctional solids with tunable properties, such as internal H-bond networks, and high chemical and thermal stability [1].
In the present work, we describe the synthesis, structural characterization, luminescent properties and proton conduction performance of a new family of isostructural cationic compounds with general formula [Ln(H4NMP)(H2O)2]Cl·2H2O [Ln = La3+, Pr3+, Sm3+, Gd3+, Tb3+, Dy3+, Ho3+, H6NMP = nitrilotris(methylphosphonic acid)]. These solids are formed by positively charge layers, which consist of isolated LnO8 polyhedra and bridge chelating NMP2- ligands, held apart by chloride ions and water molecules. This arrangement result in extended interlayer hydrogen networks with possible proton transfer pathways.
The proton conductivity of Gd3+ sample, selected as prototype of the series, was measured. In the range between range 25Âș and 80 ÂșC, the conductivity increase with the temperature up to a maximum value of 3.10-4 S·cm-1, at relative humidity of 95 %. The activation energy obtained from the Arrhenius plot (Figure 1) is in the range corresponding to a Grotthuss transfer mechanism.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech. FQM-1656; MAT2013-41836-R
A diamino-functionalized silsesquioxane pillared graphene oxide for CO2 capture
In the race for viable solutions that could slow down carbon emissions and help in meeting the climate change targets a lot of effort is being made towards the development of suitable CO2 adsorbents with high surface area, tunable pore size and surface functionalities that could enhance selective adsorption. Here, we explored the use of silsesquioxane pillared graphene oxide for CO2 capture; we modified silsesquioxane loading and processing parameters in order to obtain pillared structures with nanopores of the tailored size and surface properties to maximize the CO2 sorption capacity. Powder X-ray diffraction, XPS and FTIR spectroscopies, thermal analysis (DTA/TGA), surface area measurements and CO2 adsorption measurements were employed to characterize the materials and evaluate their performance. Through this optimisation process, materials with good CO2 storage capacities of up to 1.7/1.5 mmol g(-1) at 273 K/298 K in atmospheric pressure, were achieved
Luminescent and Proton Conducting Lanthanide Coordination Networks Based On a Zwitterionic Tripodal Triphosphonate
The synthesis, structural characterization, luminescence
properties, and proton conduction performance of a
new family of isostructural cationic 2D layered compounds are
reported. These have the general formula [Ln(H4NMP)-
(H2O)2]Cl·2H2O [Ln = La3+, Pr3+, Sm3+, Eu3+, Gd3+, Tb3+,
Dy3+, Ho3+, H6NMP = nitrilotris(methylphosphonic acid)],
and contain Clâ as the counterion. In the case of Ce3+, a 1D
derivative, [Ce2(H3NMP)2(H2O)4]·4.5H2O, isostructural with
the known lanthanum compound has been isolated by simply
crystallization at room temperature. The octa-coordinated
environment of Ln3+ in 2D compounds is composed by six
oxygen atoms from three different ligands and two oxygens
from each bound water. Two of the three phosphonate groups
act as both chelating and bridging linkers, while the third phosphonate group acts solely as a bridging moiety. The materials are
stable at low relative humidity at less at 170 °C. However, at high relative humidity transform to other chloride-free phases,
including the 1D structure. The proton conductivity of the 1D materials varies in a wide range, the highest values corresponding
to the La derivative (Ï â 2 Ă 10â3 S·cmâ1 at RH 95% and 80 °C). A lower proton conductivity, 3 Ă 10â4 S·cmâ1, was measured
for [Gd(H4NMP)(H2O)2]Cl·2H2O at 80 °C, which remains stable under the work conditions used. Absorption and
luminescence spectra were recorded for selected [Ln(H4NMP)(H2O)2]Cl·2H2O compounds. In all of them, the observed
transitions are attributed solely to fâf transitions of the lanthanide ions present, as the H4NMP2â organic group has no
measurable absorption or luminescence properties.Proyecto nacional MAT2013-41836-R (MINECO) y Proyecto de la Junta de AndaluciÌa P12-FQM-165
One-Year Water-Stable and Porous Bi(III) Halide Semiconductor with Broad-Spectrum Antibacterial Performance
Hybrid metal halide semiconductors are a unique family of materials with immense potential for numerous applications. For this to materialize, environmental stability and toxicity deficiencies must be simultaneously addressed. We report here a porous, visible light semiconductor, namely, (DHS)Bi2I8 (DHS = [2.2.2] cryptand), which consists of nontoxic, earth-abundant elements, and is water-stable for more than a year. Gas- and vapor-sorption studies revealed that it can selectively and reversibly adsorb H2O and D2O at room temperature (RT) while remaining impervious to N2 and CO2. Solid-state NMR measurements and density functional theory (DFT) calculations verified the incorporation of H2O and D2O in the molecular cages, validating the porous nature. In addition to porosity, the material exhibits broad band-edge light emission centered at 600 nm with a full width at half-maximum (fwhm) of 99 nm, which is maintained after 6 months of immersion in H2O. Moreover, (DHS)Bi2I8 exhibits bacteriocidal action against three Gram-positive and three Gram-negative bacteria, including antibiotic-resistant strains. This performance, coupled with the recorded water stability and porous nature, renders it suitable for a plethora of applications, from solid-state batteries to water purification and disinfection
Sustainable multicomponent indole synthesis with broad scope
The most preferred heterocyclic indole core was de novo assembled by an innovative 2-step reaction from inexpensive and broadly available anilines, glyoxal dimethyl acetal, formic acid and isocyanides involving an Ugi multicomponent reaction followed by an acid induced cyclization. As opposed to many other indoles syntheses, our method delivers under mild and benign conditions using ethanol as solvent and no metal catalyst. The scope of the reactions was scouted and 20 derivatives are described.</p
CCDC 2174979: Experimental Crystal Structure Determination
Related Article: Xiaofang Lei, Giasemi K. Angeli, Constantinos G. Neochoritis, Alexander Dömling|2022|Green Chemistry|||doi:10.1039/D2GC02060B,An entry from the Cambridge Structural Database, the worldâs repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
CCDC 2174980: Experimental Crystal Structure Determination
Related Article: Xiaofang Lei, Giasemi K. Angeli, Constantinos G. Neochoritis, Alexander Dömling|2022|Green Chemistry|||doi:10.1039/D2GC02060B,An entry from the Cambridge Structural Database, the worldâs repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.