scholarly journals Buchwald–Hartwig Amination of Aryl Halides with Heterocyclic Amines in the Synthesis of Highly Fluorescent Benzodifuran-Based Star-Shaped Organic Semiconductors

2021 ◽  
Author(s):  
Mariusz J. Bosiak ◽  
Alicja A. Zielińska ◽  
Piotr Trzaska ◽  
Dariusz Kędziera ◽  
Jörg Adams
Keyword(s):  
Organic Semiconductors ◽  
Aryl Halides ◽  
Heterocyclic Amines

Copper-(II) Catalyzed N -Formylation and N -Acylation of Aromatic, Aliphatic, and Heterocyclic Amines and a Preventive Study in the C-N Cross Coupling of Amines with Aryl Halides

ChemCatChem ◽  
2018 ◽  
Vol 10 (17) ◽  
pp. 3907-3913 ◽  
Author(s):  
Rahul B. Sonawane ◽  
Nishant K. Rasal ◽  
Dattatraya S. Bhange ◽  
Sangeeta V. Jagtap
Keyword(s):  
Cross Coupling ◽  
Aryl Halides ◽  
Heterocyclic Amines

Energetic Control of Redox-Active Polymers Towards Safe Organic Bioelectronic Materials

2019 ◽  
Author(s):  
Alexander Giovannitti ◽  
Reem B. Rashid ◽  
Quentin Thiburce ◽  
Bryan D. Paulsen ◽  
Camila Cendra ◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Organic Semiconductors ◽  
Side Reaction ◽  
Semiconducting Polymers ◽  
Side Reactions ◽  
Redox Active ◽  
Donor Acceptor ◽  
Electrochemical Devices ◽  
Biological Environment ◽  
Device Operation

<p>Avoiding faradaic side reactions during the operation of electrochemical devices is important to enhance the device stability, to achieve low power consumption, and to prevent the formation of reactive side‑products. This is particularly important for bioelectronic devices which are designed to operate in biological systems. While redox‑active materials based on conducting and semiconducting polymers represent an exciting class of materials for bioelectronic devices, they are susceptible to electrochemical side‑reactions with molecular oxygen during device operation. We show that this electrochemical side reaction yields hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), a reactive side‑product, which may be harmful to the local biological environment and may also accelerate device degradation. We report a design strategy for the development of redox-active organic semiconductors based on donor-acceptor copolymers that prevent the formation of H<sub>2</sub>O<sub>2</sub> during device operation. This study elucidates the previously overlooked side-reactions between redox-active conjugated polymers and molecular oxygen in electrochemical devices for bioelectronics, which is critical for the operation of electrolyte‑gated devices in application-relevant environments.</p>

Quantitative Image Analysis of Fractal-like Thin Films of Organic Semiconductors

2018 ◽  
Author(s):  
Weikun Zhu ◽  
Erfan Mohammadi ◽  
Ying Diao
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Image Analysis ◽  
Fractal Dimension ◽  
Organic Semiconductors ◽  
Film Growth ◽  
Electronic Device ◽  
Significant Control ◽  
Semiconductor Thin Films ◽  
Two Parameters

Morphology modulation offers significant control over organic electronic device performance. However, morphology quantification has been rarely carried out via image analysis. In this work, we designed a MATLAB program to evaluate two key parameters describing morphology of small molecule semiconductor thin films: fractal dimension and film coverage. We then employ this program in a case study of meniscus-guided coating of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C<sub>8</sub>-BTBT) under various conditions to analyze a diverse and complex morphology set. The evolution of morphology in terms of fractal dimension and film coverage was studied as a function of coating speed. We discovered that combined fractal dimension and film coverage can quantitatively capture the key characteristics of C<sub>8</sub>-BTBT thin film morphology; change of these two parameters further inform morphology transition. Furthermore, fractal dimension could potentially shed light on thin film growth mechanisms.

Mild Temperature Copper-Catalyzed Amination of Aryl Halides with Aqueous Ammonia in the Presence of Pyridyldiketone Ligands

2019 ◽  
Author(s):  
Racha Abed Ali Abdine ◽  
Anna Walczak ◽  
Sultan Abu A Aeash ◽  
Gracjan Kurpik ◽  
Artur R. Stefankiewicz ◽  
...  
Keyword(s):  
Catalytic System ◽  
Aqueous Ammonia ◽  
Aryl Halides ◽  
Efficient Coupling ◽  
Ambidentate Ligand ◽  
Mild Temperature

Ambidentate ligand pyridyldiketones were used in combination with copper to catalyze maintain of aryl halides under very mild temperatures. This novel catalytic system allow efficient coupling in one of the smoothest conditions ever reported in literature.

Design and Synthesis of Two-Dimensional Covalent Organic Frameworks with Four-Arm Cores: Prediction of Remarkable Ambipolar Charge-Transport Properties

2019 ◽  
Author(s):  
Simil Thomas ◽  
Hong Li ◽  
Raghunath R. Dasari ◽  
Austin Evans ◽  
William Dichtel ◽  
...  
Keyword(s):  
Charge Transport ◽  
Organic Semiconductors ◽  
Density Functional ◽  
Polymer Networks ◽  
Two Dimensional ◽  
Covalent Organic Frameworks ◽  
X Ray Diffraction ◽  
Zinc Porphyrin ◽  
Design And Synthesis ◽  
Predicted Values

<p>We have considered three two-dimensional (2D) π-conjugated polymer networks (i.e., covalent organic frameworks, COFs) materials based on pyrene, porphyrin, and zinc-porphyrin cores connected <i>via</i> diacetylenic linkers. Their electronic structures, investigated at the density functional theory global-hybrid level, are indicative of valence and conduction bands that have large widths, ranging between 1 and 2 eV. Using a molecular approach to derive the electronic couplings between adjacent core units and the electron-vibration couplings, the three π-conjugated 2D COFs are predicted to have ambipolar charge-transport characteristics with electron and hole mobilities in the range of 65-95 cm<sup>2</sup>V<sup>-1</sup>s<sup>-1</sup>. Such predicted values rank these 2D COFs among the highest-mobility organic semiconductors. In addition, we have synthesized the zinc-porphyrin based 2D COF and carried out structural characterization via powder X-ray diffraction and surface area analysis, which demonstrates the feasability of these electroactive networks.</p>

Carbon-Heteroatom Cross-Coupling via an Electronically Excited Nickel (II) Complex

2019 ◽  
Author(s):  
Randolph Escobar ◽  
Jeffrey Johannes
Keyword(s):  
Energy Transfer ◽  
Functional Groups ◽  
Cross Coupling ◽  
Reductive Elimination ◽  
Aryl Halides ◽  
Coupling Reactions ◽  
General Methodology ◽  
Cross Coupling Reactions ◽  
Electronically Excited ◽  
Energy Transfer Pathway

<div>While carbon-heteroatom cross coupling reactions have been extensively studied, many methods are specific and</div><div>limited to a set of substrates or functional groups. Reported here is a method that allows for C-O, C-N and C-S cross coupling reactions under one general methodology. We propose that an energy transfer pathway, in which an iridium photosensitizer produces an excited nickel (II) complex, is responsible for the key reductive elimination step that couples aryl halides to 1° and 2° alcohols, anilines, thiophenols, carbamates and sulfonamides.</div>

Efficient Electron Injection into Organic Semiconductors Induced by Hydrogen Bonds

2019 ◽  
pp. 840
Author(s):  
Hirohiko Fukagawa ◽  
Munehiro Hasegawa ◽  
Katsuyuki Morii ◽  
Kazuma Suzuki ◽  
Tsubasa Sasaki ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Organic Semiconductors ◽  
Electron Injection

HUMAN EXPOSURE TO BIOLOGICALLY ACTIVE HETEROCYCLIC AROMATIC AMINES ARISING FROM THERMAL PROCESSING OF PROTEIN RICH FOOD

2019 ◽  
Vol 72 (8) ◽  
pp. 1542-1550 ◽  
Author(s):  
Beata Janoszka ◽  
Agnieszka Nowak ◽  
Magdalena Szumska ◽  
Ewa Śnieżek ◽  
Krystyna Tyrpień-Golder
Keyword(s):  
Heat Treatment ◽  
Aromatic Amines ◽  
Human Exposure ◽  
High Protein ◽  
Heterocyclic Amines ◽  
Heterocyclic Aromatic Amines ◽  
International Agency ◽  
Processed Meat ◽  
Protein Food ◽  
Risk Of Cancer

Frequent consumption of thermally processed meat was classified by the International Agency for Research on Cancer to directly carcinogenic agents for humans. During the heat treatment of high protein food, mutagenic and carcinogenic, as well as neurotoxic heterocyclic aromatic amines are formed. Epidemiological studies confirm that exposure to some of these compounds may increase the risk of cancer in humans, especially the colon cancer. Most heterocyclic amines contain fried and grilled meat products, and the lowest content of these compounds can be found in boiled and slightly baked dishes. The use of spices and vegetable additives with antioxidant properties allows to obtain dishes with reduced content of these xenobiotics. An effective way to reduce human exposure to cancerogenic amines may be simultaneous consumption, together with meat dishes, products containing fiber which can adsorb molecules of heterocyclic amines in the gastrointestinal tract, as well as enrichment of the diet in the crucifers plants, as isothiocyanates released from them can inhibit the metabolic activation processes of heterocyclic amines. Raising the public awareness of the formation of mutagenic and carcinogenic compounds, including heterocyclic aromatic amines, during the intensive heat treatment of high protein food, as well as the dissemination of knowledge on the conditions regarding the preparation of dishes with reduced content of such compounds could become one of the components of cancer prevention programs in Poland.

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