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1. Ambient volatile organic compounds at a receptor site in the Pearl River Delta region: Variations, source apportionment and effects on ozone formation

Author:
Meng, Yao; Song, Junwei; Zeng, Lewei; Zhang, Yingyi; Zhao, Yan; Liu, Xufei; Guo, Hai; Zhong, Liuju; Ou, Yubo; Zhou, Yan; Zhang, Tao; Yue, Dingli; Lai, Senchao
Source:
Journal of environmental sciences (China) 2022 v.111 pp. 104-117
ISSN:
1001-0742
Subject:
aromatic compounds,   etc   ; air; diurnal variation; evaporation; gasoline; models; ozone; pollution; river deltas; rivers; solvents; volatile organic compounds; China;     Show all 13 Subjects
Abstract:
... We present the continuously measurements of volatile organic compounds (VOCs) at a receptor site (Wan Qing Sha, WQS) in the Pearl River Delta (PRD) region from September to November of 2017. The average mixing ratios of total VOCs (TVOCs) was 36.3 ± 27.9 ppbv with the dominant contribution from alkanes (55.5%), followed by aromatics (33.3%). The diurnal variation of TVOCs showed a strong photochem ...
DOI:
10.1016/j.jes.2021.02.024

2. A New Ligand Design Based on London Dispersion Empowers Chiral Bismuth–Rhodium Paddlewheel Catalysts

Author:
Singha, Santanu; Buchsteiner, Michael; Bistoni, Giovanni; Goddard, Richard; Fürstner, Alois
Source:
Journal of the American Chemical Society 2021 v.143 no.15 pp. 5666-5673
ISSN:
1520-5126
Subject:
aromatic compounds,   etc   ; carbenes; ligands;     Show all 3 Subjects
Abstract:
... Heterobimetallic bismuth–rhodium paddlewheel complexes with phenylglycine ligands carrying TIPS-groups at the meta-positions of the aromatic ring exhibit outstanding levels of selectivity in reactions of donor/acceptor and donor/donor carbenes; at the same time, the reaction rates are much faster and the substrate scope is considerably wider than those of previous generations of chiral [BiRh] cata ...
DOI:
10.1021/jacs.1c01972

3. Preparation of 6-substituted phenanthridines from o-biaryl ketoximes via the Beckmann rearrangement

Author:
Nakamura, Kohei; Kobayashi, Eiji; Moriyama, Katsuhiko; Togo, Hideo
Source:
Tetrahedron 2021 v.91 pp. 132244
ISSN:
0040-4020
Subject:
aromatic compounds,   etc   ; Lewis acids; phenanthridines;     Show all 3 Subjects
Abstract:
... Treatment of anti alkyl o-biaryl ketoximes and anti aryl o-biaryl ketoximes with Tf₂O at 120 °C, followed by quenching with Et₃N gave 6-alkylphenanthridines and 6-arylphenanthridines in good yields, respectively. These reactions proceeded through the O-triflation of the ketoximes, the Beckmann rearrangement, and the electrophilic cyclization of the formed nitrilium group onto the aromatic ring. © ...
DOI:
10.1016/j.tet.2021.132244

4. Regioselective C–H Trifluoromethylation of Aromatic Compounds by Inclusion in Cyclodextrins

Author:
Lu, Xu; Kawazu, Ryohei; Song, Jizhou; Yoshigoe, Yusuke; Torigoe, Takeru; Kuninobu, Yoichiro
Source:
Organic letters 2021 v.23 no.11 pp. 4327-4331
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; additives; cyclodextrins; regioselectivity;     Show all 4 Subjects
Abstract:
... A regioselective radical C–H trifluoromethylation of aromatic compounds was developed using cyclodextrins (CDs) as additives. The C–H trifluoromethylation proceeded with high regioselectivity to afford the product in good yield, even on the gram scale. In the presence of CDs, some substrates underwent a single trifluoromethylation selectively, whereas mixtures of single- and double-trifluoromethyl ...
DOI:
10.1021/acs.orglett.1c01259

5. Understanding the Activation of Air-Stable Ir(COD)(Phen)Cl Precatalyst for C–H Borylation of Aromatics and Heteroaromatics

Author:
Slack, Eric D.; Colacot, Thomas J.
Source:
Organic letters 2021 v.23 no.5 pp. 1561-1565
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; alcohols; catalysts; solvents;     Show all 4 Subjects
Abstract:
... A newly developed robust catalyst [Ir(COD)(Phen)Cl] (A) was used for the C–H borylation of three dozen aromatics and heteroaromatics with excellent yield and selectivity. Activation of the catalyst was identified by the use of catalytic amounts of water, alcohols, etc., when B₂pin₂ was used in noncoordinating solvents, while for THF catalytic use of HBpin was required. The results were on par with ...
DOI:
10.1021/acs.orglett.0c04210

6. Poly(dimethylsiloxane) and oligo(dimethylsiloxane) solvent effects on aromatic donor–acceptor interactions

Author:
Amemori, Shogo; Kikuchi, Kyoka; Mizuno, Motohiro
Source:
Chemical communications 2021 v.57 no.9 pp. 1141-1144
ISSN:
1364-548X
Subject:
aromatic compounds,   etc   ; siloxanes; solubility; solvents;     Show all 4 Subjects
Abstract:
... Solvents with a wide range of polarities, including poly(dimethylsiloxane) and oligo(dimethylsiloxane), were used to evaluate aromatic donor–acceptor interactions between pyrene and pyromellitic diimide derivatives. The donor–acceptor interactions were stronger in siloxane solvents than in aliphatic solvents, possibly because of the poor solubility of the aromatics in siloxanes. ...
DOI:
10.1039/d0cc06638a

7. Discovering the role of substrate in aldehyde hydrogenation

Author:
Cattaneo, Stefano; Capelli, Sofia; Stucchi, Marta; Bossola, Filippo; Dal Santo, Vladimiro; Araujo-Lopez, Eduard; Sharapa, Dmitry I.; Studt, Felix; Villa, Alberto; Chieregato, Alessandro; Vandegehuchte, Bart D.; Prati, Laura
Source:
Journal of catalysis 2021 v.399 pp. 162-169
ISSN:
0021-9517
Subject:
aromatic compounds,   etc   ; adsorption; benzaldehyde; catalytic activity; hydrogenation;     Show all 5 Subjects
Abstract:
... In this manuscript, we investigated in detail one of the critical parameters that govern the reactivity of the carbonylic group toward hydrogenation and hydrodeoxygenation: the effect of the side chains of aldehydes. We observed that the presence of a π-electron conjugation on the side chains strongly affects the conversion of aldehydes to alcohols and hydrocarbons under the reaction conditions st ...
DOI:
10.1016/j.jcat.2021.05.012

8. Catalytic conversion of light alkanes to aromatics by metal-containing HZSM-5 zeolite catalysts—A review

Author:
Liu, Dongyang; Cao, Liyuan; Zhang, Guohao; Zhao, Liang; Gao, Jinsen; Xu, Chunming
Source:
Fuel processing technology 2021 v.216 pp. 106770
ISSN:
0378-3820
Subject:
aromatic compounds,   etc   ; aromatization; dehydrogenation; industry; oxygen; zeolites;     Show all 6 Subjects
Abstract:
... The directly catalytic conversion of C₂-C₆ alkanes to aromatics has aroused widespread interest from both academia and industry because of the growing demand for aromatics. Compared with pure HZSM-5 zeolites, the addition of metal species is required to enhance the selectivity of BTX by inhibiting undesirable side reactions. This paper reviewed the research progress of aromatization for light alka ...
DOI:
10.1016/j.fuproc.2021.106770

9. Experimental Observation of New Phase, Determination of Loading-Path of Amorphous State and Loading–Path Dependent Phase Transitions for Pyridine around Freezing Pressure via Raman Modes in Low Wavenumber

Author:
Su, Hao; Li, Xiangdong; Zhong, Cheng; Mai, Di; Liang, Wentao; Wang, Ruijie; Dai, Rucheng; Wang, Zhongping; Zhang, Zengming
Source:
Journal of physical chemistry 2021 v.125 no.20 pp. 11159-11165
ISSN:
1932-7455
Subject:
aromatic compounds,   etc   ; ambient temperature; pyridines; solidification;     Show all 4 Subjects
Abstract:
... Pyridine is a key element of the aromatic compound family, with complicated phases under high pressure. In this paper, Raman modes at low frequencies are employed to investigate the phase evolution of pyridine using a self-built loading and unloading setup with a 0.1 GPa increment. Raman specifically determines the solidification pressure of pyridine at room temperature, which is 2.1 GPa. The pyri ...
DOI:
10.1021/acs.jpcc.1c01369

10. Delocalization Effects and Tunable Emission in a Class of Charged Cyclazines with Nitrogen on the Periphery

Author:
Kurian, Jais; Shurooque, Kanneth S.; Ramkumar, Venkatachalam; Chakkumkumarath, Lakshmi; Kannoth M., Muraleedharan
Source:
Organic letters 2021 v.23 no.9 pp. 3354-3358
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; X-ray diffraction; carbon; nitrogen;     Show all 4 Subjects
Abstract:
... A new class of cyclazine analogues with periphery reminiscent of an aza[10]annulene framework, tethered internally by an sp³ carbon, is presented. In depth structure analysis based on NMR and X-ray diffraction data gave a deeper insight into the effect of electron delocalization on their structure and properties. A characteristic change in chemical shift positions suggested an aromatic ring curren ...
DOI:
10.1021/acs.orglett.1c00827

11. Pdᴵᴵ insertion-triggered meso-carbon extrusion of N-fused pentaphyrin to form N-fused sapphyrin Pdᴵᴵ complexes

Author:
Nakai, Akito; Yoneda, Tomoki; Tanaka, Takayuki; Osuka, Atsuhiro
Source:
Chemical communications 2021 v.57 no.24 pp. 3034-3037
ISSN:
1364-548X
Subject:
aromatic compounds,   etc   ; chemical communication; extrusion; oxidation;     Show all 4 Subjects
Abstract:
... meso-Carbon extrusion of N-fused [22]pentaphyrin(1.1.1.1.1) occurred upon its Pdᴵᴵ complexation, giving N-fused [22]pentaphyrin (1.1.1.1.0) ([22]sapphyrin) Pdᴵᴵ complexes 5 and 6 as 22π aromatic compounds. Oxidation of 5 with DDQ and Sc(OTf)₃ gave directly C–N linked dimer 7. ...
DOI:
10.1039/d1cc00518a

12. Groundwater contamination by fluorinated aromatics: Benzotrifluoride and its derivatives

Author:
Lava, Roberto; Calore, Francesco; Mazzola, Massimo; Moretto, Carlo Giovanni; Pretto, Ugo; Salmaso, Paola; Bizzotto, Alessandro; Carvutto, Rosi; Acerbi, Mauro; Tommasi, Jgor; Marcomini, Antonio
Source:
Chemosphere 2021 v.265 pp. 129029
ISSN:
0045-6535
Subject:
aromatic compounds,   etc   ; groundwater; groundwater contamination; surveys; Italy;     Show all 5 Subjects
Abstract:
... Benzotrifluoride (BTF) and its derivatives (BTFs) were found in the groundwater of the Veneto region (Italy) as a result of industrial contamination dating back to the 1970s. In the first survey, BTF and 6 BTFs were identified, out of which 4-chloro-3nitrobenzotrifluoride (3N4CBTF) was the only quantified analyte (concentration up to 1 mg L⁻¹) and was used to trace the contamination plume. A surve ...
DOI:
10.1016/j.chemosphere.2020.129029

13. Efficient unified synthesis of diverse bridged polycyclic scaffolds using a complexity-generating ‘stitching’ annulation approach

Author:
Rice, Scott; Cox, Daniel J.; Marsden, Stephen P.; Nelson, Adam
Source:
Chemical communications 2021 v.57 no.5 pp. 599-602
ISSN:
1364-548X
Subject:
aromatic compounds,   etc   ; arylation; nitrogen; regioselectivity; stereospecificity;     Show all 5 Subjects
Abstract:
... Regioselective and stereospecific directed C–H arylation of simple amine substrates, and cyclisation, delivered 30 diverse, three-dimensional scaffolds. The unified approach significantly expanded the range of bridged ring systems that contain both a nitrogen atom and an aromatic ring. ...
DOI:
10.1039/d0cc06975b

14. Sign inversion in magnetic circularly polarised luminescence of fused aromatics with 1.6 T N-up/S-up Faraday geometry

Author:
Toda, Hayato; Hara, Nobuyuki; Fujiki, Michiya; Imai, Yoshitane
Source:
RSC advances 2021 v.11 no.3 pp. 1581-1585
ISSN:
2046-2069
Subject:
aromatic compounds,   etc   ; geometry; luminescence; magnetic fields;     Show all 4 Subjects
Abstract:
... Although 12 diamagnetic fused aromatics with or without substituents exhibit mirror-symmetric magnetic circularly polarised luminescence (MCPL) through N-up and S-up Faraday geometries under a magnetic field intensity of 1.6 T, their signs (single and multiple) and magnitudes depend strongly on either the aromatic structures or the peripheral positions of the substituents. ...
DOI:
10.1039/d0ra09233a

15. Metallaaromatic Chemistry: History and Development

Author:
Chen, Dafa; Hua, Yuhui; Xia, Haiping
Source:
Chemical reviews 2020 v.120 no.23 pp. 12994-13086
ISSN:
1520-6890
Subject:
aromatic compounds,   etc   ; chemistry; prediction;     Show all 3 Subjects
Abstract:
... Since the prediction of the existence of metallabenzenes in 1979, metallaaromatic chemistry has developed rapidly, due to its importance in both experimental and theoretical fields. Now six major types of metallaromatic compounds, metallabenzenes, metallabenzynes, heterometallaaromatics, dianion metalloles, metallapentalenes and metallapentalynes (also termed carbolongs), and spiro metalloles, hav ...
DOI:
10.1021/acs.chemrev.0c00392

16. Access-dispersion-recovery strategy for enhanced mitigation of heavy crude oil pollution using magnetic nanoparticles decorated bacteria

Author:
Cao, Yiqi; Zhang, Baiyu; Zhu, Zhiwen; Rostami, Masoumeh; Dong, Guihua; Ling, Jingjing; Lee, Kenneth; Greer, Charles W.; Chen, Bing
Source:
Bioresource technology 2021 v.337 pp. 125404
ISSN:
0960-8524
Subject:
aromatic compounds,   etc   ; Rhodococcus erythropolis; bioremediation; magnetism; oils; petroleum; pollution;     Show all 7 Subjects
Abstract:
... Heavy crude oil (HCO) pollution has gained global attention, but traditional bioremediating practices demonstrate limited effectiveness. This study developed magnetic nanoparticles decorated bacteria (MNPB) using an oil-degrading and biosurfactant-producing Rhodococcus erythropolis species and identified a novel access-dispersion-recovery strategy for enhanced HCO pollution mitigation. The strateg ...
DOI:
10.1016/j.biortech.2021.125404

17. Different approaches to convert waste polyolefins into automotive fuels via hydrocracking with a NiW/HY catalyst

Author:
Vela, Francisco J.; Palos, Roberto; Trueba, David; Bilbao, Javier; Arandes, José M.; Gutiérrez, Alazne
Source:
Fuel processing technology 2021 v.220 pp. 106891
ISSN:
0378-3820
Subject:
aromatic compounds,   etc   ; batch systems; catalysts; oils; polyethylene; pyrolysis oils;     Show all 6 Subjects
Abstract:
... Different approaches to upgrade waste plastic and vacuum gasoil (VGO) blends via hydrocracking have been investigated. The approaches have consisted on using different charges: (i) neat VGO; (ii) neat plastic pyrolysis oil (PPO); (iii) a PPO/VGO blend; (iv) a high-density polyethylene (HDPE)/VGO blend; and (v) a ternary PPO/HDPE/VGO blend. The runs have been conducted in a batch reactor at: 400–44 ...
DOI:
10.1016/j.fuproc.2021.106891

18. Using an oxidation flow reactor to understand the effects of gasoline aromatics and ethanol levels on secondary aerosol formation

Author:
Kuittinen, Niina; McCaffery, Cavan; Zimmerman, Stephen; Bahreini, Roya; Simonen, Pauli; Karjalainen, Panu; Keskinen, Jorma; Rönkkö, Topi; Karavalakis, Georgios
Source:
Environmental research 2021 v.200 pp. 111453
ISSN:
0013-9351
Subject:
aromatic compounds,   etc   ; aerosols; carbon; ethanol; gasoline; oxidation; particulates; research;     Show all 8 Subjects
Abstract:
... Fuel type and composition affect tailpipe emissions and secondary aerosol production from mobile sources. This study assessed the influence of gasoline fuels with varying levels of aromatics and ethanol on the primary emissions and secondary aerosol formation from a flexible fuel vehicle equipped with a port fuel injection engine. The vehicle was exercised over the LA92 and US06 driving cycles usi ...
DOI:
10.1016/j.envres.2021.111453

19. Evaluating refinery configurations for deriving sustainable aviation fuel from ethanol or syncrude

Author:
Petersen, Abdul M.; Chireshe, Farai; Okoro, Oseweuba; Gorgens, Johann; Van Dyk, Johan
Source:
Fuel processing technology 2021 v.219 pp. 106879
ISSN:
0378-3820
Subject:
aromatic compounds,   etc   ; aviation; bioethanol; butanol; capital costs; ethanol; feedstocks; patents;     Show all 8 Subjects
Abstract:
... This study presents novel comprehensive comparisons of alternative refinery configurations for sustainable aviation fuels (SAF) from bio-ethanol or Fischer-Tropsch bio-syncrude through techno-economic evaluations. Simulations were conducted in Aspen Plus, followed by evaluating the minimum aviation-fuel selling price (MINAFSP) at specific feedstock price, and the maximum tolerable prices of ethano ...
DOI:
10.1016/j.fuproc.2021.106879

20. Facile pinacol coupling of aliphatic ketones by Brook rearrangement in the presence of samarium species

Author:
Wang, Xincan; Xie, Guanqun; Zhao, Yanfei; Zheng, Ke; Fang, Yanxiong; Wang, Xiaoxia
Source:
Tetrahedron letters 2021 v.72 pp. 153069
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; aldehydes; carbonyl compounds; couplings; ketones; methodology; samarium;     Show all 7 Subjects
Abstract:
... Herein we report a practical pinacol coupling reaction, in which ketones (aldehydes) react smoothly with Sm and TMSBr to afford the diol products with Sm(II) or (III) siliyl species generated in situ. This reported method affords poor yields for aromatic ketone substrates and good yields for aliphatic ketones. Therefore, it distinguishes from most reductive coupling approaches that are more effect ...
DOI:
10.1016/j.tetlet.2021.153069