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1. Macrocyclic pentamers functionalised around their periphery as potential building blocks

Author:
Nam, Seong; Ware, David C.; Brothers, Penelope J.
Source:
RSC advances 2019 v.9 no.15 pp. 8389-8393
ISSN:
2046-2069
Subject:
aromatic compounds,   etc   ; chemical reactions; moieties;     Show all 3 Subjects
Abstract:
... The elaboration of a five-fold symmetric macrocyclic aromatic pentamer bearing peripheral benzyloxy and hydroxyl groups is described. These could be used to explore further functionalisation for use as pentagonal building blocks. The internal fluorine-substituted macrocycle has been prepared via a one-pot procedure which is an improvement on the stepwise chain growth approach reported in the liter ...
DOI:
10.1039/c8ra10446h

2. Access to 5-fluoroisoxazoles via the nitrosation of geminal bromo-fluoro arylcyclopropanes

Author:
Bondarenko, Oksana B.; Vinogradov, Aleksandr A.; Komarov, Arseniy I.; Karetnikov, Georgy L.; Zyk, Nikolai V.; Holt, Tina; Kutateladze, Andrei G.
Source:
Tetrahedron 2019 v.75 no.20 pp. 2861-2865
ISSN:
0040-4020
Subject:
aromatic compounds,   etc   ; chemical reactions; chemical structure; regioselectivity;     Show all 4 Subjects
Abstract:
... A new method for the synthesis of 3-aryl-5-fluoroisoxazoles via the reaction of nitrosonium chlorosulfate with 2-aryl-1-bromo-1-fluorocyclopropanes containing acceptor substituents in the aromatic ring has been developed. The reaction proceeds highly regioselectively thus providing 3-aryl-5-fluoroisoxazoles in good yields. The structure of isoxazoles was corroborated by the DU8+ hybrid DFT/paramet ...
DOI:
10.1016/j.tet.2019.03.054

3. Cyclopenta[b]thiopyran and cyclopenta[b]selenopyran based heteroarenes: electronic communication between S- and/or Se-fused aromatics

Author:
Qiao, Yanjun; Lu, Yifan; Chen, Weinan; Chen, Yijing; Baumgarten, Martin; Zhou, Gang
Source:
Chemical communications 2019 v.55 no.35 pp. 5107-5110
ISSN:
1364-548X
Subject:
aromatic compounds,   etc   ; electron transfer; moieties; oxidation;     Show all 4 Subjects
Abstract:
... S- and Se-heteroarenes containing cyclopenta[b]thiopyran and/or cyclopenta[b]selenopyran moieties have been synthesized via PtCl₂-catalyzed ring-expanding cycloaromatizations. Intervalence charge transfer bands can be observed for the three heteroarenes upon chemical oxidation, suggesting the electronic communication between S- and/or Se-fused aromatics. ...
DOI:
10.1039/c9cc01761e

4. Control of surface reactivity towards unsaturated CC bonds and H over Ni-based intermetallic compounds in semi-hydrogenation of acetylene

Author:
Song, Yuanjun; Laursen, Siris
Source:
Journal of catalysis 2019 v.372 pp. 151-162
ISSN:
0021-9517
Subject:
aromatic compounds,   etc   ; boron; ethylene; hydrogenation; nickel; stoichiometry;     Show all 6 Subjects
Abstract:
... Intermetallic compounds composed of transition metals and semimetals or post-transition metals have been shown to exhibit elevated selectivity in olefins and aromatics production and other reactions that require control of CC activation and functionalization. The vast number of element combinations available for intermetallic compound production necessitates down-selecting to isolate catalytically ...
DOI:
10.1016/j.jcat.2019.02.018

5. Triptycene Tripods for the Formation of Highly Uniform and Densely Packed Self-Assembled Monolayers with Controlled Molecular Orientation

Author:
Ishiwari, Fumitaka; Nascimbeni, Giulia; Sauter, Eric; Tago, Hiromu; Shoji, Yoshiaki; Fujii, Shintaro; Kiguchi, Manabu; Tada, Tomofumi; Zharnikov, Michael; Zojer, Egbert; Fukushima, Takanori
Source:
Journal of the American Chemical Society 2019 v.141 no.14 pp. 5995-6005
ISSN:
1520-5126
Subject:
aromatic compounds,   etc   ; adsorption; gold; moieties; simulation models;     Show all 5 Subjects
Abstract:
... When employing self-assembled monolayers (SAMs) for tuning surface and interface properties, organic molecules that enable strong binding to the substrate, large-area structural uniformity, precise alignment of functional groups, and control of their density are highly desirable. To achieve these goals, tripod systems bearing multiple bonding sites have been developed as an alternative to conventi ...
DOI:
10.1021/jacs.9b00950

6. Hydrogen-Bond-Controlled Formal Meta-Selective C–H Transformations and Regioselective Synthesis of Multisubstituted Aromatic Compounds

Author:
Wang, Jie; Torigoe, Takeru; Kuninobu, Yoichiro
Source:
Organic letters 2019 v.21 no.5 pp. 1342-1346
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; chemical reactions; moieties; regioselectivity;     Show all 4 Subjects
Abstract:
... The meta-selective introduction of functional groups into aromatic substrates was successfully achieved by hydrogen-bond-controlled meta-selective C–H borylation and successive conversion of the boryl group to other functional groups. By this method a wide range of functional groups could be introduced without isolation of the borylated intermediates. The desired meta-functionalized aromatic produ ...
DOI:
10.1021/acs.orglett.9b00030

7. Hydrogenation of CO₂ into aromatics over a ZnCrOₓ–zeolite composite catalyst

Author:
Zhang, Junfeng; Zhang, Meng; Chen, Shuyao; Wang, Xiaoxing; Zhou, Zeling; Wu, Yingquan; Zhang, Tao; Yang, Guohui; Han, Yizhuo; Tan, Yisheng
Source:
Chemical communications 2019 v.55 no.7 pp. 973-976
ISSN:
1364-548X
Subject:
aromatic compounds,   etc   ; carbon dioxide; catalysts; hydrocarbons; hydrogenation;     Show all 5 Subjects
Abstract:
... A ZnCrOₓ-ZnZSM-5 composite catalyst was used for CO₂ hydrogenation into hydrocarbons especially aromatics (Aro). 81.1% Aro selectivity in C₅₊ hydrocarbons (mainly C₅–₁₁) was obtained at 320 °C, corresponding to 19.9% CO₂ conversion, 29.8% total hydrocarbons (HCₜ) selectivity and 69.7% C₅₊ selectivity in HCₜ. Our optimized STY of Aro is the highest ever reported. ...
DOI:
10.1039/c8cc09019j

8. Solution and solvation enthalpies of aromatic derivitives in binary mixtures. Dipole moment and dielectric properties

Author:
Petrov, Artem A.; Rakipov, Ilnaz T.; Khachatrian, Artashes A.; Varfolomeev, Mikhail A.; Akhmadiyarov, Aydar A.; Ismagilova, Rezeda R.; Vereshchagina, Yana A.; Solomonov, Boris N.
Source:
Thermochimica acta 2019 v.676 pp. 1-6
ISSN:
0040-6031
Subject:
aromatic compounds,   etc   ; carbon; dielectric properties; enthalpy; nitrobenzenes; solvents;     Show all 6 Subjects
Abstract:
... In the present work a thermochemistry of solution and solvation of mono- and di-substituted chloro- and nitrobenzenes in binary mixtures was studied. The infinite dilution solution enthalpies of 1,2-dichlorobenzene,1,4-dichlorobenzene, 1,2- dinitrobenzene, 1,4-dinitrobenzene, 1-chloro-2-nitrobenzene and 1-chloro-4-nitrobenzene in binary mixtures of benzene-cyclohexane, benzene-acetonitrile, carbon ...
DOI:
10.1016/j.tca.2019.03.028

9. Pyrolysis of the aromatic-poor and aromatic-rich fractions of bio-oil: Characterization of coke structure and elucidation of coke formation mechanism

Author:
Xiong, Zhe; Syed-Hassan, Syed Shatir A.; Hu, Xun; Guo, Junhao; Qiu, Jihua; Zhao, Xingyu; Su, Sheng; Hu, Song; Wang, Yi; Xiang, Jun
Source:
Applied energy 2019 v.239 pp. 981-990
ISSN:
0306-2619
Subject:
aromatic compounds,   etc   ; biofuels; elemental composition; moieties; pyrolysis; steam; temperature;     Show all 7 Subjects
Abstract:
... Coke formation is one major problem during thermal conversion of bio-oil and its main components. Fundamental knowledge about the evolution of the structure of cokes is a prerequisite towards a deep understanding of coking of bio-oil. This study investigates the structure (morphology, elemental composition, O-containing functional groups and aromatic structures) of cokes generated from the pyrolys ...
DOI:
10.1016/j.apenergy.2019.01.253

10. Synthesis of a Porphyrin(2.1.2.1) Nanobelt and Its Ability To Bind Fullerene

Author:
Xue, Songlin; Kuzuhara, Daiki; Aratani, Naoki; Yamada, Hiroko
Source:
Organic letters 2019 v.21 no.7 pp. 2069-2072
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; chemical structure; condensation reactions; electrons; fullerene; oxidation; porphyrins;     Show all 7 Subjects
Abstract:
... This Letter details a simple and effective method to synthesize a porphyrin(2.1.2.1)-based nanobelt NBNi₃ via condensation reactions of 1,2,4,5-tetra(pyrrol-2-yl)benzene and benzaldehydes. NBNi₃ consists of three arch-shaped porphyrins(2.1.2.1) and benzene linkages with a C₃ₕ-symmteric structure. The concave-shaped cavity of NBNi₃ behaves as a C₆₀ receptor by capturing two C₆₀ cooperatively. Addit ...
DOI:
10.1021/acs.orglett.9b00329

11. Manganese-catalyzed ring-opening carbonylation of cyclobutanol derivatives

Author:
Meyer, Tim; Yin, Zhiping; Wu, Xiao-Feng
Source:
Tetrahedron letters 2019
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; chemical reactions; chemical structure; cleavage (chemistry); esters;     Show all 5 Subjects
Abstract:
... Herein, we report a manganese-catalyzed ring-opening carbonylation of cyclobutanol derivatives through cyclic CC bond cleavage. The reaction happens via a radical-mediated pathway to selectively generate 1,5-ketoesters. A variety of substrates with substituents on the aromatic ring reacted with linear alcohols of different chain lengths. Obtained aliphatic esters are very attractive since they are ...
DOI:
10.1016/j.tetlet.2019.02.028

12. A Theoretical Study on the Mechanism of the Oxidative Deborylation/C–C Coupling Reaction of Borepin Derivatives

Author:
Özen, Cihan; Shoji, Yoshiaki; Fukushima, Takanori; Maeda, Satoshi
Source:
Journal of organic chemistry 2019 v.84 no.4 pp. 1941-1950
ISSN:
1520-6904
Subject:
aromatic compounds,   etc   ; boron; ligands; moieties; organic chemistry; oxidants; oxidation; oxygen;     Show all 8 Subjects
Abstract:
... One-electron oxidation of borepin derivatives that consists of a boron-containing seven-membered ring has been reported to cause deborylation/C–C coupling, yielding aromatic compounds. The reaction can be achieved not only by transition metal compounds but also by oxidants without transition metal such as O₂ and other organic compounds. Despite numerous experimental attempts, the mechanism of this ...
DOI:
10.1021/acs.joc.8b02917

13. SIRT1 inhibitory compounds from the roots of Codonopsis pilosula

Author:
Li, Xiao-Zhen; Cheng, Li-Zhi; Yan, Yong-Ming; Liu, Bao-Hua; Cheng, Yong-Xian
Source:
Journal of Asian natural products research 2019 v.21 no.1 pp. 25-32
ISSN:
1477-2213
Subject:
aromatic compounds,   etc   ; Codonopsis pilosula; dose response; roots; spectroscopy; China;     Show all 6 Subjects
Abstract:
... Three new compounds, pilosulinene A (1), pilosulinols A (2), and B (3), along with seven known compounds, were isolated from the roots of Codonopsis pilosula cultivated in Xundian County of Yunnan Province. The structures of new compounds were established by spectroscopic methods. In particular, the presence of an aromatic ring in the structure of 1 makes it intriguing. The inhibitory activity of ...
DOI:
10.1080/10286020.2017.1422491

14. Synthesis of functionalized pyrroloindolines via a visible-light-induced radical cascade reaction: rapid synthesis of (±)-flustraminol B

Author:
Wu, Kui; Du, Yuliu; Wei, Zheng; Wang, Ting
Source:
Chemical communications 2018 v.54 no.54 pp. 7443-7446
ISSN:
1364-548X
Subject:
aromatic compounds,   etc   ; alcohols; chemical reactions;     Show all 3 Subjects
Abstract:
... The development of visible-light-induced synthesis of functionalized pyrroloindolines via a radical cascade reaction is reported. The reaction shows a broad substrate scope and highlights the mild nature of the reaction conditions. A range of substitutions on indole aromatic rings and N-centers is well tolerated, including a free allylic alcohol. Relying on the strategy, a rapid synthesis of (±)-f ...
DOI:
10.1039/c8cc03575j

15. Iridium-Catalyzed Intramolecular Asymmetric Allylic Alkylation of Hydroxyquinolines: Simultaneous Weakening of the Aromaticity of Two Consecutive Aromatic Rings

Author:
Yang, Ze-Peng; Jiang, Ru; Zheng, Chao; You, Shu-Li
Source:
Journal of the American Chemical Society 2018 v.140 no.8 pp. 3114-3119
ISSN:
1520-5126
Subject:
aromatic compounds,   etc   ; alkylation; catalysts; enantioselectivity;     Show all 4 Subjects
Abstract:
... Intramolecular asymmetric allylic alkylation reactions of 5- and 7-hydroxyquinoline derivatives were realized by a chiral Ir/NHC catalyst. A series of functionalized cyclic enones were afforded in excellent yields (up to 99%) and high enantioselectivity (up to 97% ee). Theoretical computations revealed that the aromaticity of the two consecutive rings of hydroxyquinoline substrates is significantl ...
DOI:
10.1021/jacs.8b00136

16. Emission of intermediate volatility organic compounds from a ship main engine burning heavy fuel oil

Author:
Lou, Haijun; Hao, Yuejiao; Zhang, Weiwei; Su, Penghao; Zhang, Fan; Chen, Yingjun; Feng, Daolun; Li, Yifan
Source:
Journal of environmental sciences (China) 2019 v.84 pp. 197-204
ISSN:
1001-0742
Subject:
aromatic compounds,   etc   ; aerosols; burning; chemical composition; emissions; emissions factor; fuel oils; models; polycyclic compounds; ships;     Show all 10 Subjects
Abstract:
... Intermediate volatility organic compounds (IVOCs) are crucial precursors of secondary organic aerosol (SOA). In this study, gaseous IVOCs emitted from a ship main engine burning heavy fuel oil (HFO) were investigated on a test bench, which could simulate the real-world operations and emissions of ocean-going ships. The chemical compositions, emission factors (EFs) and volatility distributions of I ...
DOI:
10.1016/j.jes.2019.04.029

17. Characterization of the major aroma-active compounds in Keitt mango juice: Comparison among fresh, pasteurization and high hydrostatic pressure processing juices

Author:
Zhang, Wentao; Dong, Pan; Lao, Fei; Liu, Jiayi; Liao, Xiaojun; Wu, Jihong
Source:
Food chemistry 2019 v.289 pp. 215-222
ISSN:
0308-8146
Subject:
aromatic compounds,   etc   ; cultivars; high pressure treatment; mango juice; mangoes; odor compounds; odors; pasteurization; principal component analysis;     Show all 9 Subjects
Abstract:
... The commercial mango cultivar Keitt lacks a theoretical foundation for aroma control during processing. To discriminate the aroma-active compounds in fresh mango juice, odor activity value (OAV) and detection frequency analysis (DFA) were used collaboratively. A total of 12 components were identified as major aroma-active compounds, among which 2,4-dimethylstyrene was firstly confirmed as an aroma ...
DOI:
10.1016/j.foodchem.2019.03.064

18. The interaction mechanism of oligopeptides containing aromatic rings with β-cyclodextrin and its derivatives

Author:
Li, Jiaqi; Geng, Sheng; Wang, Yu; Lv, Yonghui; Wang, Huabin; Liu, Benguo; Liang, Guizhao
Source:
Food chemistry 2019 v.286 pp. 441-448
ISSN:
0308-8146
Subject:
aromatic compounds,   etc   ; antioxidants; beta-cyclodextrin; computer simulation; hydrophobic bonding; nuclear magnetic resonance spectroscopy; oligopeptides;     Show all 7 Subjects
Abstract:
... We investigate the formation mechanism of supramolecular complexes of four antioxidant oligopeptides (YW, WY, WYS, and WYSL) with β-cyclodextrin (β-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD) and 6-O-α-maltosyl-β-cyclodextrin (M-β-CD) by combined computational and experimental methods. The formation of complexes is determined by UV, IR and DSC, and the rank-ordered acquired stability of the comple ...
DOI:
10.1016/j.foodchem.2019.02.021

19. A practice-oriented method for the analysis of coplanar tetra- to heptachlorinated terphenyls

Author:
Wichmann, H.; Schäfer, K.; Bahadir, M.
Source:
Chemosphere 2019 v.224 pp. 195-201
ISSN:
0045-6535
Subject:
aromatic compounds,   etc   ; combustion; detection limit; ecotoxicology; gas chromatography; lipids; mass spectrometry; sediments; soil;     Show all 9 Subjects
Abstract:
... Polychlorinated terphenyls (PCT) were produced and used on industrial scale in the last century. Today, PCT are formed especially during combustion and some chemical conversion processes. As being persistent, low volatile chlorinated aromatics, they are continuously emitted into the environment from primary and secondary sources. Blatant knowledge gaps exist concerning environmental behavior, toxi ...
DOI:
10.1016/j.chemosphere.2019.02.107

20. Efficiency and proportions of waste tyre pyrolysis products depending on the reactor type—A review

Author:
Lewandowski, Witold M.; Januszewicz, Katarzyna; Kosakowski, Wojciech
Source:
Journal of analytical and applied pyrolysis 2019 v.140 pp. 25-53
ISSN:
0165-2370
Subject:
aromatic compounds,   etc   ; carbon; catalysts; coal; electricity; heat; kilns; market prices; oils; pyrolysis; recycling; tires; wastes;     Show all 13 Subjects
Abstract:
... This article discusses the current use of different pyrolytic reactors, their constructions and operating principles regarding the yields of main products of waste tyre pyrolytic recycling. Whether one makes a larger or smaller profit, or even a loss due to a surcharge being levied on waste tyre recycling, depends on the sale of the pyrolysis products (gas, char, oil), the proportions and market p ...
DOI:
10.1016/j.jaap.2019.03.018