scholarly journals Synthesis and crystal structure of 1,3-bis(4-hydroxyphenyl)-1H-imidazol-3-ium chloride

2019 ◽  
Vol 75 (9) ◽  
pp. 1311-1315
Author(s):  
R. Tyler Mertens ◽  
Sean R. Parkin ◽  
Samuel G. Awuah
Keyword(s):  
Close Contact ◽  
Functional Materials ◽  
Building Blocks ◽  
Imidazole Ring ◽  
Ring Closure ◽  
High Yield ◽  
Imidazolium Salt ◽  
Step Procedure ◽  
Out Of Plane ◽  
Donor Acceptor

Imidazolium salts are common building blocks for functional materials and in the synthesis of N-heterocyclic carbene (NHC) as σ-donor ligands for stable metal complexes. The title salt, 1,3-bis(4-hydroxyphenyl)-1H-imidazol-3-ium chloride (IOH·Cl), C15H13N2O2 +·Cl−, is a new imidazolium salt with a hydroxy functionality. The synthesis of IOH·Cl was achieved in high yield via a two-step procedure involving a diazabutadiene precursor followed by ring closure using trimethylchlorosilane and paraformaldehyde. The structure of IOH·Cl consists of a central planar imidazolium ring (r.m.s. deviation = 0.0015 Å), with out-of-plane phenolic side arms. The dihedral angles between the 4-hydroxyphenyl substituents and the imidazole ring are 55.27 (7) and 48.85 (11)°. In the crystal, O—H...Cl hydrogen bonds connect the distal hydroxy groups and Cl− anions in adjacent asymmetric units, one related by inversion (−x + 1, −y + 1, −z + 1) and one by the n-glide (x − {1\over 2}, −y + {1\over 2}, z − {1\over 2}), with donor–acceptor distances of 2.977 (2) and 3.0130 (18) Å, respectively. The phenolic rings are each π–π stacked with their respective inversion-related [(−x + 1, −y + 1, −z + 1) and (−x, −y + 1, −z + 1)] counterparts, with interplanar distances of 3.560 (3) and 3.778 (3) Å. The only other noteworthy intermolecular interaction is an O...O (not hydrogen bonded) close contact of 2.999 (3) Å between crystallographically different hydroxy O atoms on translationally adjacent molecules (x + 1, y, x + 1).

scholarly journals SYNTHESIS OF A 1,2,3-TRIAZOLE-CONTAINING MACROCYCLE BASED ON THE "CLICK CHEMISTRY" REACTION AND ANALYSIS OF ITS PLANAR CHIRALITY USING NMR AND DFT CALCULATIONS

2020 ◽  
pp. 55-61
Author(s):  
H. Yampolska ◽  
S. Kharchenko ◽  
A. Kozytskyi ◽  
A. Kyrylchuk ◽  
Z. Voitenko ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Click Chemistry ◽  
Protein Interactions ◽  
Variable Temperature ◽  
Triazole Ring ◽  
Building Blocks ◽  
Ring Closure ◽  
Amide Bond ◽  
High Yield ◽  
Planar Chirality

Macrocycles represent previously unexplored promising drug candidates, that can be useful for treating protein-protein interactions. Atropoisomerism is an inherent feature of the natural macrocyclic peptides that is significant for their activity and selectivity, and, therefore, should be introduced into newly synthesized macrocycles. Synthesis of the libraries of artificial macrocycles faces many challenges due to their structure and size. Herein we report on the preparation of a 16-membered macrocycle containing 1,2,3-triazole ring, spiro-piperidine, and phenyl moieties, as well as a chiral carbon atom. Our approach to the macrocycle was inspired by the "build/couple/pair" (B/C/P) strategy, a part of diversity-oriented synthesis methodology. We have employed readily accessible starting materials and robust synthetic procedures which allowed us to obtain the target macrocycle in a high yield. Standard methods of amide bond formation were used for the coupling of macrocycle building blocks. Click chemistry azide-alkyne cycloaddition was exploited at the final ring closure step. The assignment of signals in 1H and 13C NMR spectra of the macrocycle was performed using a series of 2D NMR techniques. The macrocycle displayed planar chirality, which, in a combination with a stereocenter with the known configuration, was sufficient to propose possible structures of diastereomers. The diastereomers could differ by the relative position of triazole ring. Their racemization could occur through a "rope skipping" motion involving the cyclic chain crossing the plane of 1,2,3-triazole ring. The supposed structures of diastereomers were corroborated by means of a various NMR spectroscopy techniques and DFT calculations. Analysis of the amide NH chemical shift temperature coefficients coupled with the data on optimized geometries obtained by DFT convincingly demonstrated that the intramolecular hydrogen bonds play a major role in stabilization of the diastereomer structures. According to the variable temperature NMR experiment, the interconversion of two diastereomers did not occur even at heating up to 70 °C.

scholarly journals Bacterial cellulose spheroids as building blocks for 3D and patterned living materials and for regeneration

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Joaquin Caro-Astorga ◽  
Kenneth T. Walker ◽  
Natalia Herrera ◽  
Koon-Yang Lee ◽  
Tom Ellis
Keyword(s):  
Bacterial Cellulose ◽  
Building Blocks ◽  
Genetically Engineered ◽  
High Yield ◽  
Synthetic Materials ◽  
Chemical Inputs ◽  
First Time ◽  
3D Shapes ◽  
Promising Avenue ◽  
Living Materials

AbstractEngineered living materials (ELMs) based on bacterial cellulose (BC) offer a promising avenue for cheap-to-produce materials that can be programmed with genetically encoded functionalities. Here we explore how ELMs can be fabricated in a modular fashion from millimetre-scale biofilm spheroids grown from shaking cultures of Komagataeibacter rhaeticus. Here we define a reproducible protocol to produce BC spheroids with the high yield bacterial cellulose producer K. rhaeticus and demonstrate for the first time their potential for their use as building blocks to grow ELMs in 3D shapes. Using genetically engineered K. rhaeticus, we produce functionalized BC spheroids and use these to make and grow patterned BC-based ELMs that signal within a material and can sense and report on chemical inputs. We also investigate the use of BC spheroids as a method to regenerate damaged BC materials and as a way to fuse together smaller material sections of cellulose and synthetic materials into a larger piece. This work improves our understanding of BC spheroid formation and showcases their great potential for fabricating, patterning and repairing ELMs based on the promising biomaterial of bacterial cellulose.

scholarly journals Core-Substituted Naphthalene-diimides (cNDI) and Related Derivatives: Versatile Scaffold for Supramolecular Assembly and Functional Materials

2021 ◽  
Author(s):  
Anurag Mukherjee ◽  
Suhrit Ghosh
Keyword(s):  
Photophysical Properties ◽  
Supramolecular Assembly ◽  
Functional Materials ◽  
Building Blocks ◽  
Short Review ◽  
Molecular Engineering ◽  
Organic Optoelectronics ◽  
Naphthalene Diimide ◽  
Naphthalene Diimides ◽  
Derivatives Of

Naphthalene-diimide (NDI) derived building blocks have been explored extensively for supramolecular assembly as they exhibit attractive photophysical properties, suitable for applications in organic optoelectronics. Core-substituted derivatives of the NDI chromophore (cNDI) differ significantly from the parent NDI dye in terms of optical and redox properties. Adequate molecular engineering opportunities and substitution-dependent tunable optoelectronic properties make cNDI derivatives highly promising candidates for supramolecular assembly and functional material. This short review discusses recent development in the area of functional supramolecular assemblies based on cNDIs and related molecules.

scholarly journals MXenes for future nanophotonic device applications

Nanophotonics ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1831-1853
Author(s):  
Jaeho Jeon ◽  
Yajie Yang ◽  
Haeju Choi ◽  
Jin-Hong Park ◽  
Byoung Hun Lee ◽  
...  
Keyword(s):  
Solar Cells ◽  
Transition Metal ◽  
Wide Spectrum ◽  
Building Blocks ◽  
Optoelectronic Device ◽  
High Yield ◽  
Saturable Absorption ◽  
Nanophotonic Device ◽  
Wide Range ◽  
Device Applications

AbstractTwo-dimensional (2D) layers of transition metal carbides, nitrides, or carbonitrides, collectively referred to as MXenes, are considered as the new family of 2D materials for the development of functional building blocks for optoelectronic and photonic device applications. Their advantages are based on their unique and tunable electronic and optical properties, which depend on the modulation of transition metal elements or surface functional groups. In this paper, we have presented a comprehensive review of MXenes to suggest an insightful perspective on future nanophotonic and optoelectronic device applications based on advanced synthesis processes and theoretically predicted or experimentally verified material properties. Recently developed optoelectronic and photonic devices, such as photodetectors, solar cells, fiber lasers, and light-emitting diodes are summarized in this review. Wide-spectrum photodetection with high photoresponsivity, high-yield solar cells, and effective saturable absorption were achieved by exploiting different MXenes. Further, the great potential of MXenes as an electrode material is predicted with a controllable work function in a wide range (1.6–8 eV) and high conductivity (~104 S/cm), and their potential as active channel material by generating a tunable energy bandgap is likewise shown. MXene can provide new functional building blocks for future generation nanophotonic device applications.

scholarly journals Integrated Optical Phased Arrays for Beam Forming and Steering

2021 ◽  
Vol 11 (9) ◽  
pp. 4017
Author(s):  
Yongjun Guo ◽  
Yuhao Guo ◽  
Chunshu Li ◽  
Hao Zhang ◽  
Xiaoyan Zhou ◽  
...  
Keyword(s):  
Near Infrared ◽  
Phased Arrays ◽  
Mechanical Stability ◽  
Building Blocks ◽  
High Yield ◽  
Beam Forming ◽  
Integrated Optical ◽  
Optical Phased Arrays ◽  
Infrared Spectral ◽  
Spectral Ranges

Integrated optical phased arrays can be used for beam shaping and steering with a small footprint, lightweight, high mechanical stability, low price, and high-yield, benefiting from the mature CMOS-compatible fabrication. This paper reviews the development of integrated optical phased arrays in recent years. The principles, building blocks, and configurations of integrated optical phased arrays for beam forming and steering are presented. Various material platforms can be used to build integrated optical phased arrays, e.g., silicon photonics platforms, III/V platforms, and III–V/silicon hybrid platforms. Integrated optical phased arrays can be implemented in the visible, near-infrared, and mid-infrared spectral ranges. The main performance parameters, such as field of view, beamwidth, sidelobe suppression, modulation speed, power consumption, scalability, and so on, are discussed in detail. Some of the typical applications of integrated optical phased arrays, such as free-space communication, light detection and ranging, imaging, and biological sensing, are shown, with future perspectives provided at the end.

scholarly journals Amyloid fibril-directed synthesis of silica core–shell nanofilaments, gels, and aerogels

2019 ◽  
Vol 116 (10) ◽  
pp. 4012-4017 ◽  
Author(s):  
Yiping Cao ◽  
Sreenath Bolisetty ◽  
Gianna Wolfisberg ◽  
Jozef Adamcik ◽  
Raffaele Mezzenga
Keyword(s):  
Amyloid Fibril ◽  
Functional Materials ◽  
Building Blocks ◽  
Inorganic Materials ◽  
Core Shell ◽  
Shear Stresses ◽  
Bending Rigidity ◽  
Widespread Application ◽  
Nonmonotonic Dependence ◽  
Silica Core

Amyloid fibrils have evolved from purely pathological materials implicated in neurodegenerative diseases to efficient templates for last-generation functional materials and nanotechnologies. Due to their high intrinsic stiffness and extreme aspect ratio, amyloid fibril hydrogels can serve as ideal building blocks for material design and synthesis. Yet, in these gels, stiffness is generally not paired by toughness, and their fragile nature hinders significantly their widespread application. Here we introduce an amyloid-assisted biosilicification process, which leads to the formation of silicified nanofibrils (fibril–silica core–shell nanofilaments) with stiffness up to and beyond ∼20 GPa, approaching the Young’s moduli of many metal alloys and inorganic materials. The silica shell endows the silicified fibrils with large bending rigidity, reflected in hydrogels with elasticity three orders of magnitude beyond conventional amyloid fibril hydrogels. A constitutive theoretical model is proposed that, despite its simplicity, quantitatively interprets the nonmonotonic dependence of the gel elasticity upon the filaments bundling promoted by shear stresses. The application of these hybrid silica–amyloid hydrogels is demonstrated on the fabrication of mechanically stable aerogels generated via sequential solvent exchange, supercriticalCO2removal, and calcination of the amyloid core, leading to aerogels of specific surface area as high as 993m2/g, among the highest values ever reported for aerogels. We finally show that the scope of amyloid hydrogels can be expanded considerably by generating double networks of amyloid and hydrophilic polymers, which combine excellent stiffness and toughness beyond those of each of the constitutive individual networks.

scholarly journals Constructing Large 2D Lattices Out of DNA-Tiles

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1502
Author(s):  
Johannes M. Parikka ◽  
Karolina Sokołowska ◽  
Nemanja Markešević ◽  
J. Jussi Toppari
Keyword(s):  
Self Assembly ◽  
Dna Nanotechnology ◽  
Building Blocks ◽  
High Yield ◽  
Dna Nanostructures ◽  
Liquid Interfaces ◽  
Basic Principles ◽  
Dna Tiles ◽  
One Step ◽  
Solid Liquid

The predictable nature of deoxyribonucleic acid (DNA) interactions enables assembly of DNA into almost any arbitrary shape with programmable features of nanometer precision. The recent progress of DNA nanotechnology has allowed production of an even wider gamut of possible shapes with high-yield and error-free assembly processes. Most of these structures are, however, limited in size to a nanometer scale. To overcome this limitation, a plethora of studies has been carried out to form larger structures using DNA assemblies as building blocks or tiles. Therefore, DNA tiles have become one of the most widely used building blocks for engineering large, intricate structures with nanometer precision. To create even larger assemblies with highly organized patterns, scientists have developed a variety of structural design principles and assembly methods. This review first summarizes currently available DNA tile toolboxes and the basic principles of lattice formation and hierarchical self-assembly using DNA tiles. Special emphasis is given to the forces involved in the assembly process in liquid-liquid and at solid-liquid interfaces, and how to master them to reach the optimum balance between the involved interactions for successful self-assembly. In addition, we focus on the recent approaches that have shown great potential for the controlled immobilization and positioning of DNA nanostructures on different surfaces. The ability to position DNA objects in a controllable manner on technologically relevant surfaces is one step forward towards the integration of DNA-based materials into nanoelectronic and sensor devices.

scholarly journals Reaction of α-amido sulfones with functionalized nitrocompounds: a new two-step synthesis of N-alkoxycarbonyl-2,5-disubstituted pyrroles

RSC Advances ◽  
2014 ◽  
Vol 4 (81) ◽  
pp. 43258-43261 ◽  
Author(s):  
Roberto Ballini ◽  
Serena Gabrielli ◽  
Alessandro Palmieri ◽  
Marino Petrini
Keyword(s):  
Ring Closure ◽  
Cascade Process ◽  
Step Procedure

N-Alkoxycarbonyl-2,5-disubstituted pyrroles can be readily prepared by a new two-step procedure involving a preliminary addition of nitro ketals to α-amido sulfones followed by an acid promoted ring closure of the obtained intermediates through a cascade process.

scholarly journals Connected Lead Zirconate Titanate Nanodot Arrays for Perspective Functional Materials

2013 ◽  
Vol 2013 ◽  
pp. 1-6
Author(s):  
M. Waegner ◽  
A. Finn ◽  
G. Suchaneck ◽  
G. Gerlach ◽  
L. M. Eng
Keyword(s):  
Lead Zirconate Titanate ◽  
Short Circuit ◽  
Functional Materials ◽  
Piezoresponse Force Microscopy ◽  
Lead Zirconate ◽  
Lateral Direction ◽  
Flexible Polymer ◽  
Zirconate Titanate ◽  
Out Of Plane ◽  
The Matrix

We describe the fabrication of lead zirconate titanate (PZT) nanodisc arrays isolated by a polymer layer and contacted with a top electrode. PZT thin films were deposited by multitarget sputtering onto a platinum/titanium bottom electrode and structured by means of nanosphere lithography. To guarantee short-circuit-free deposition of a top electrode, the space between the nanostructures was filled by a polymer. Two approaches for the filling are demonstrated: (a) imprinting and (b) skim coating. Single nanodiscs embedded in a flexible polymer matrix have two major advantages. First, taking into account the flexibility of the matrix, they can vibrate in lateral direction and, second, due to shrinking to the nanoscale, predominant directions of the polarization form, such as vortex- or bubble-like domain patterns. Piezoresponse force microscopy was performed on patterned and nonpatterned samples with and without a top electrode to check the local piezoresponse. Comparison of the different samples revealed an increase in lateral piezoactivity for patterned samples with Ni/Cr electrode while the out-of-plane piezoresponse remained constant. Gold electrodes limit the piezoresponse in both measured directions.

scholarly journals Origin of perpendicular magnetic anisotropy in amorphous thin films

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Lordan ◽  
Guannan Wei ◽  
Paul McCloskey ◽  
Cian O’Mathuna ◽  
Ansar Masood
Keyword(s):  
Thin Films ◽  
Magnetic Anisotropy ◽  
Perpendicular Magnetic Anisotropy ◽  
Functional Materials ◽  
Spin Reorientation ◽  
Amorphous Films ◽  
Amorphous Thin Films ◽  
Magnetic Performance ◽  
Out Of Plane ◽  
Sputtering Pressure

AbstractThe emergence of perpendicular magnetic anisotropy (PMA) in amorphous thin films, which eventually transforms the magnetic spins form an in-plane to the out-of-plane configuration, also known as a spin-reorientation transition (SRT), is a fundamental roadblock to attain the high flux concentration advantage of these functional materials for broadband applications. The present work is focused on unfolding the origin of PMA in amorphous thin films deposited by magnetron sputtering. The amorphous films were deposited under a broad range of sputtering pressure (1.6–6.2 mTorr), and its effect on the thin film growth mechanisms was correlated to the static global magnetic behaviours, magnetic domain structure, and dynamic magnetic performance. The films deposited under low-pressure revealed a dominant in-plane uniaxial anisotropy along with an emerging, however feeble, perpendicular component, which eventually evolved as a dominant PMA when deposited under high-pressure sputtering. This change in the nature of anisotropy redefined the orientation of spins from in-plane to out-of-plane. The SRT in amorphous films was attributed to the dramatic change in the growth mechanism of disorder atomic structure from a homogeneously dispersed to a porous columnar microstructure. We suggest the origin of PMA is associated with the columnar growth of the amorphous films, which can be eluded by a careful selection of a deposition pressure regime to avoid its detrimental effect on the soft magnetic performance. To the author’s best knowledge, no such report links the sputtering pressure as a governing mechanism of perpendicular magnetisation in technologically important amorphous thin films.

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