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1. Designing the efficient lithium diffusion and storage channels based on graphdiyne

Author:
Li, Xiaodong; Wang, Ning; He, Jianjiang; Yang, Ze; Tu, Zeyi; Zhao, Fuhua; Wang, Kun; Yi, Yuanping; Huang, Changshui
Source:
Carbon 2020 v.162 pp. 579-585
ISSN:
0008-6223
Subject:
aromatic compounds,   etc   ; anodes; carbon; lithium; lithium batteries;     Show all 5 Subjects
Abstract:
... We report the first synthesized sp-sp²-sp³ hybridized two-dimensional porous carbon, methyl substituted graphdiyne (MsGDY). The conjugated sp and sp² carbons construct a conductive framework and well-distributed pores, and methyl units (sp³-C) are introduced into the well-distributed pores by coupling on benzene ring, which directly results in enlarged layer spacing (0.41 nm). Combining the advant ...
DOI:
10.1016/j.carbon.2020.03.004

2. Syntheses of diaza(hetera)2[1.1.1.1]paracyclophanes by Chapman rearrangement

Author:
Takemura, Hiroyuki; Morikawa, Akino; Tanaka, Mari; Tatsumi, Akane; Kubota, Yukiko; Kaji, Natsuko; Hasegawa, Ayako; Kumamoto, Fumiko; Obara, Tomoko; Iwanaga, Tetsuo; Sako, Katsuya
Source:
Tetrahedron letters 2020 v.61 no.13 pp. 151673
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; chemical reactions; chemical structure; models;     Show all 4 Subjects
Abstract:
... Diaza(hetera)₂[1.1.1.1]paracyclophanes (PCPs) were prepared by the Chapman rearrangement. This is the first synthesis of highly strained and heteroatom-containing PCPs by a rearrangement reaction. The structures of the two precursors, [3.1.3.1]PCPs and [1.1.1.1]PCPs, are discussed in detail. In contrast to the small strain of [3.1.3.1]PCPs, [1.1.1.1]PCPs release their large strain by bending the a ...
DOI:
10.1016/j.tetlet.2020.151673

3. The Tetraethylphosphorodiamidate (OP(O)(NEt₂)₂) Directed Metalation Group (DMG). Directed ortho and Lateral Metalation and the Phospha Anionic Fries Rearrangement

Author:
Alessi, Manlio; Patel, Jignesh J.; Zumbansen, Kristina; Snieckus, Victor
Source:
Organic letters 2020 v.22 no.6 pp. 2147-2151
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; chemical reactions; chemical structure;     Show all 3 Subjects
Abstract:
... We report on the tetraethylphosphorodiamidate (−OP(O)(NEt₂)₂) group as an effective directed metalation group (DMG). Lithiation-electrophile quench of 1 provides a general synthesis of ortho-substituted aryl and naphthyl phosphorodiamidates 4–8. We also describe the phospha anionic ortho-Fries (AoF) rearrangement of the phosphorodiamidates 1a,1b → 2 or 3 and its vinylogous counterpart to the ortho ...
DOI:
10.1021/acs.orglett.0c00094

4. Practical and efficient synthesis of aryl trifluoromethyl sulfones from arylsulfonyl chlorides with Umemoto’s reagent II

Author:
Zhou, Xiaocong; Hu, Dufen; He, Xinyi; Li, Yuanqiang; Chu, Youqun; She, Yuanbin
Source:
Tetrahedron letters 2020 v.61 no.5 pp. 151465
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; chemical reactions; chemical structure;     Show all 3 Subjects
Abstract:
... A practical and efficient method for the synthesis of aryl trifluoromethyl sulfones has been developed by a tandem reaction of arylsulfonyl chlorides with Umemoto’s reagent II. The advantageous features of this method are simple operation, mild reaction conditions, wide scope of substrates, high yield of products, and easy scalability. ...
DOI:
10.1016/j.tetlet.2019.151465

5. Design Rules for Improving the Cycling Stability of High-Performance Donor–Acceptor-Type Electrochromic Polymers

Author:
Han, Yuntao; Xing, Zhen; Ma, Pinyi; Li, Su; Wang, Chong; Jiang, Zhenhua; Chen, Zheng
Source:
ACS applied materials & interfaces 2020 v.12 no.6 pp. 7529-7538
ISSN:
1944-8252
Subject:
aromatic compounds,   etc   ; color; electrochemistry; moieties; polymers;     Show all 5 Subjects
Abstract:
... Although high-performance donor–acceptor (D–A)-type polymers have received much attention as an important class of electrochromic (EC) materials, the related studies have mostly focused on the influence of D and A units on the band gap, onset potential, and switching time, leaving the effect of D–A structures on cycling lifetime underexplored. Herein, we design and synthesize a series of poly(aryl ...
DOI:
10.1021/acsami.9b19214

6. Ionic liquid-mediated benzoyl transfer-coupling in the Suzuki and Sonogashira reactions and aryl transfer-coupling by decarbonylative Heck reaction, using N-Benzoyl-saccharin (NBSac) as reagent

Author:
Malunavar, Shruti S.; Sutar, Suraj M.; Prabhala, Pavankumar; Kalkhambkar, Rajesh G.; Laali, Kenneth K.
Source:
Tetrahedron letters 2020 v.61 no.24 pp. 151987
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; Suzuki reaction; catalytic activity; chemical structure; solvents;     Show all 5 Subjects
Abstract:
... The efficacy of N-benzoyl-saccharin (NBSac) as reagent for selective benzoyl transfer-coupling in the Suzuki reaction in BMIM-IL/[PAIM][NTf₂] as solvent/base, and in the Sonogashira reaction employing guanidinium-IL (GIL) as solvent, are demonstrated. Decarbonylative aryl transfer-coupling occurs in the Heck reaction employing GIL as solvent. The reactions are catalyzed by Pd(OAc)₂ or NiCl₂(dppp), ...
DOI:
10.1016/j.tetlet.2020.151987

7. Highly stereoselective monofluoroolefination: Facile access to (E)-α-fluorinated arylvinyl sulfones from trifluoromethyl α-fluorinated arylsulfonyl gem-diols

Author:
Fang, Xiang; Zhou, Jun; Wang, Wang; Yang, Xueyan; Wu, Fanhong
Source:
Tetrahedron letters 2020 v.61 no.23 pp. 151964
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; aldehydes; chemical reactions; cis-trans isomers; stereoselectivity;     Show all 5 Subjects
Abstract:
... An excellent stereoselective direct synthesis of trisubstituted (E)-α-fluorinated arylvinyl sulfones employing trifluoromethyl α-fluorinated arylsulfonyl gem-diols and aryl aldehydes under mild reaction conditions has been developed, which affords α-fluorinated arylvinyl sulfones in high yields with E-isomer only. The desired products can be further transformed into more useful fluoroolefins throu ...
DOI:
10.1016/j.tetlet.2020.151964

8. Stereoelectronic constraints in the aryl radical cylization of phenethylenamides

Author:
Navarro-Vázquez, Armando; Domínguez, Domingo
Source:
Tetrahedron letters 2020 v.61 no.20 pp. 151871
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; chemical reactions; free radicals; moieties; regioselectivity;     Show all 5 Subjects
Abstract:
... The 7-endo-trig and 6-exo-trig cyclizations of the N-formylphenethylenamide radicals have been computationally studied at the UM062X/6–31 + G** and UPW6B95-D3 DFT levels of theory. Computations show a regioselectivity preference for the 7-endo process over the 6-exo in agreement with known experimental results. This 7-endo process takes place preferentially through a transition structure of half-b ...
DOI:
10.1016/j.tetlet.2020.151871

9. Facile entry to substituted 2-arylpiperidines via an aza-Sakurai reaction

Author:
Goodnough, Alex M.; Sahn, James J.; Martin, Stephen F.
Source:
Tetrahedron letters 2020 v.61 no.18 pp. 151777
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; aldehydes; catalytic activity; chemical reactions; chemical structure; imines;     Show all 6 Subjects
Abstract:
... An efficient route has been developed for the facile synthesis of functionalized 2-arylpiperidines that may be readily modified using straightforward transformations to create collections of novel substituted 2-arylpiperidines. The approach features a reaction cascade starting with imine formation from a known amino allylsilane and a diverse set of aryl aldehydes, followed by an acid-catalyzed aza ...
DOI:
10.1016/j.tetlet.2020.151777

10. Structural Engineering of Two-Dimensional Covalent Organic Frameworks for Visible-Light-Driven Organic Transformations

Author:
Liu, Haoran; Li, Chunzhi; Li, He; Ren, Yiqi; Chen, Jian; Tang, Jianting; Yang, Qihua
Source:
ACS applied materials & interfaces 2020 v.12 no.18 pp. 20354-20365
ISSN:
1944-8252
Subject:
aromatic compounds,   etc   ; crystal structure; dehalogenation; engineering; models; photocatalysis; semiconductors; triazines;     Show all 8 Subjects
Abstract:
... Covalent organic frameworks (COFs) emerging as a novel kind of visible light-responsive organic semiconductor have attracted extensive research attention in the field of photocatalytic organic transformations. However, the key parameters affecting their photocatalytic properties are still not clear. In this work, a series of [3 + 3] COFs with similar two-dimensional hexagonal structure but differe ...
DOI:
10.1021/acsami.0c00013

11. Dearomative Allylation of Naphthyl Cyanohydrins by Palladium Catalysis: Catalyst-Enhanced Site Selectivity

Author:
Yanagimoto, Aika; Komatsuda, Masaaki; Muto, Kei; Yamaguchi, Junichiro
Source:
Organic letters 2020 v.22 no.9 pp. 3423-3427
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; allylation; borates; catalysts; catalytic activity; chemical structure; palladium;     Show all 7 Subjects
Abstract:
... A dearomative allylation of naphthyl cyanohydrins with allyl borates and allyl stannanes under palladium catalysis was developed. At the initial stage of this study, the dearomative reaction (C4 substitution of the aromatics) was competing with benzyl substitution. To circumvent this issue, the use of palladium and meta-disubstituted triarylphosphine as the catalyst in a 1:1 ratio was found to enh ...
DOI:
10.1021/acs.orglett.0c00897

12. Trizaine-based dehydrative condensation reagents bearing carbon-substituents

Author:
Kitamura, Masanori; Komine, Sayaka; Yamada, Kohei; Kunishima, Munetaka
Source:
Tetrahedron 2020 v.76 no.12 pp. 130900
ISSN:
0040-4020
Subject:
aromatic compounds,   etc   ; Lewis acids; ammonium salts; chemical structure; condensation reactions;     Show all 5 Subjects
Abstract:
... Herein, we report on the synthesis of alkyl-, aryl-, and alkynyl-substituted chlorotriazines and their ammonium salts, and demonstrate their utility in dehydrative condensation reactions. Although the electrophilicity of these reagents is mainly dependent on the hybridization of the carbon-substituents, it was found that bulky 2,6-dimethylphenyl group-substituted reagents resulted in the highest p ...
DOI:
10.1016/j.tet.2019.130900

13. Synthesis of 3-S- and 3-Se-glycals by using R-S-S-R and R-Se-Se-R as the nucleophile precursors promoted by Hf(OTf)4 and the temperature-dependent formation of the above-mentioned 3-S- and 3-Se products

Author:
Chen, Peiran; Guo, Saisai; Zuo, Junfeng; Chu, Ruiji; He, Xu; Zhu, Guijiang
Source:
Tetrahedron letters 2020 v.61 no.12 pp. 151648
ISSN:
0040-4039
Subject:
aromatic compounds,   etc   ; Lewis bases; acetates; catalysts; chemical reactions; chemical structure;     Show all 6 Subjects
Abstract:
... By using Hf(OTf)₄ as the catalyst, under certain conditions, reaction of tri-O-acetyl-d-glucal and ((2R ,3S)-3-acetoxy-2,3-dihydrofuran-2-yl)methyl acetate with alkyl(aryl) bisulfide/alkyl(aryl) biselenide as nucleophile precursor leads to temperature-dependent formation of C-1-S/Se and C-3-S/Se product. A temperature-dependent profile of the yield of these two products is given. ...
DOI:
10.1016/j.tetlet.2020.151648

14. Peak focusing based on stationary phase thickness gradient

Author:
Li, Maxwell Wei-Hao; Zhu, Hongbo; Zhou, Menglian; She, Jinyan; Li, Ziqi; Kurabayashi, Katsuo; Fan, Xudong
Source:
Journal of chromatography 2020 v.1614 pp. 460737
ISSN:
0021-9673
Subject:
aromatic compounds,   etc   ; alkanes; ambient temperature; coatings; gas chromatography; volatile compounds;     Show all 6 Subjects
Abstract:
... This paper reports the development of a stationary phase thickness gradient gas chromatography (GC) column that enables analyte peak focusing and improves separation resolution. Theoretical analysis and simulation demonstrate focusing via a positive thickness gradient, i.e., the stationary phase thickness increases along the column. This effect was experimentally verified by coating a 5 m long cap ...
DOI:
10.1016/j.chroma.2019.460737

15. Catalytic Friedel–Crafts Alkylation of Electron Rich Aromatic Derivatives with α-Aryl Diazoacetates Mediated by Brønsted Acids

Author:
Gallo, Rafael D. C.; Momo, Patrícia B.; Day, David P.; Burtoloso, Antonio C. B.
Source:
Organic letters 2020 v.22 no.6 pp. 2339-2343
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; Bronsted acids; alkylation; catalytic activity; chemical structure; protonation;     Show all 6 Subjects
Abstract:
... The catalytic protonation of aryl diazoacetates by strong Brønsted acids, followed by a Friedel–Crafts alkylation reaction with electron rich aromatic compounds, is reported. The reaction provided in a direct fashion 24 geminal diarylacetates in yields of ≤92%. ...
DOI:
10.1021/acs.orglett.0c00540

16. Enhancing Performance of Fused-Ring Electron Acceptor Using Pyrrole Instead of Thiophene

Author:
Lu, Bing; Chen, Zhenyu; Jia, Boyu; Wang, Jiayu; Ma, Wei; Lian, Jiarong; Zeng, Pengju; Qu, Junle; Zhan, Xiaowei
Source:
ACS applied materials & interfaces 2020 v.12 no.12 pp. 14029-14036
ISSN:
1944-8252
Subject:
aromatic compounds,   etc   ; energy; photovoltaic cells; pyrroles; thiophene; transmittance;     Show all 6 Subjects
Abstract:
... Selecting suitable outermost aromatic rings of the central cores is of particular importance for the design of fused-ring electron acceptors (FREAs) because the direct electronic communication between the outermost aromatic rings and termini exerts a strong impact on the optoelectronic properties of FREAs. In most cases, the outermost rings of the FREA cores are thiophene. This work reported the f ...
DOI:
10.1021/acsami.0c00733

17. Unprecedented activity and stability on zirconium phosphates grafted mesoporous silicas for renewable aromatics production from furans

Author:
Kasipandi, Saravanan; Min Cho, Jae; Soo Park, Kyung; Shin, Chae-Ho; Wook Bae, Jong
Source:
Journal of catalysis 2020
ISSN:
0021-9517
Subject:
aromatic compounds,   etc   ; furans; phosphates; porous media; silica; zirconium;     Show all 6 Subjects
Abstract:
... The selective production of aromatic chemicals such as benzene, toluene and xylenes from biomass-derived furans are quite challenging since zeolites and other supported heterogeneous catalysts are easily deactivated by trapping oligomeric species over their pores. Herein, a series of zirconium phosphates (ZrP) grafted on ordered mesoporous architectures of silicas was prepared by nonhydrolytic sol ...
DOI:
10.1016/j.jcat.2020.02.026

18. Orthogonal arylations of 5-vinyl-1,2,4-triazoles

Author:
Azzouni, Safa; Gaucher, Anne; Prim, Damien; Efrit, Mohamed Lotfi
Source:
Tetrahedron 2020 v.76 no.8 pp. 130954
ISSN:
0040-4020
Subject:
aromatic compounds,   etc   ; amines; arylation; catalytic activity; ligands; moieties; palladium; triazoles;     Show all 8 Subjects
Abstract:
... The preparation of 1,3,5-trisubstituted 1,2,4-triazoles is described using selective orthogonal arylation sequences. Ligand free Pd-catalyzed arylation allowed installing various (het)aryl units exclusively at the vinyl fragment of N1 substituted or N1-H precursors. Successful double arylations starting from ortho, meta and para bisiodobenzenes led to extended bistriazolyl derivatives. In contrast ...
DOI:
10.1016/j.tet.2020.130954

19. Anomalous Electronic Properties of Iodous Materials: Application to High-Spin Reactive Intermediates and Conjugated Polymers

Author:
Qiu, Yunfan; Winter, Arthur H.
Source:
Journal of organic chemistry 2020 v.85 no.6 pp. 4145-4152
ISSN:
1520-6904
Subject:
aromatic compounds,   etc   ; chemical reactions; chemical structure; iodine; polymers;     Show all 5 Subjects
Abstract:
... Manipulating frontier orbital energies of aromatic molecules with substituents is key to a variety of chemical and material applications. Here, we investigate a simple strategy for achieving high-energy in-plane orbitals for aromatics simply by positioning iodine atoms next to each other. The lone pair orbitals on the iodines mix to give a high-energy in-plane σ-antibonding orbital as the highest ...
DOI:
10.1021/acs.joc.9b03289

20. Cycloaddition of Trifluoroacetaldehyde N-Triftosylhydrazone (TFHZ-Tfs) with Alkynes for Synthesizing 3-Trifluoromethylpyrazoles

Author:
Wang, Hongwei; Ning, Yongquan; Sun, Yue; Sivaguru, Paramasivam; Bi, Xihe
Source:
Organic letters 2020 v.22 no.5 pp. 2012-2016
ISSN:
1523-7052
Subject:
aromatic compounds,   etc   ; alkynes; chemical structure; cycloaddition reactions; drugs; pyrazoles;     Show all 6 Subjects
Abstract:
... A transition-metal-free [3 + 2] cycloaddition between trifluoroacetaldehyde N-triftosylhydrazone (TFHZ-Tfs) and alkynes is reported. This protocol provides an operationally simple and general method for the synthesis of diverse 3-trifluoromethylpyrazoles in good to excellent yields with broad substrate scope, including aryl, heteroaryl, and alkyl terminal alkynes, and electron-deficient internal a ...
DOI:
10.1021/acs.orglett.0c00395