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1. A photochromic carbazolyl-imidazolyl radical complex

Author:
Yasuki Kawanishi; Yasutomo Segawa; Katsuya Mutoh; Jiro Abe; Yoichi Kobayashi
Source:
Chemical communications 2022 v.58 no.32 pp. 4997-5000
ISSN:
1364-548X
Subject:
moieties,   etc   ; absorption; photosensitivity;     Show all 3 Subjects
Abstract:
... A carbazole-incorporated photochromic radical complex is synthesized. The long-wavelength photosensitivity of the photochromic reaction of the molecule is enhanced up to ∼580 nm by substituting a triphenylamine group into the 3-position of the carbazole moiety. These photochromic reactions are investigated by subpicosecond-to-microsecond transient absorption measurements. ...
DOI:
10.1039/d2cc01196d

2. Novel “turn-on” fluorescent sensors for silver (I) based on the nicotinonitriles, containing a tricyanobutadiene moiety

Author:
Ivan N. Bardasov; Anastasiya U. Alekseeva; Maria A. Shishlikova; Oleg V. Ershov
Source:
Tetrahedron letters 2022 pp. 153819
ISSN:
0040-4039
Subject:
moieties,   etc   ; fluorescence; silver;     Show all 3 Subjects
Abstract:
... The novel turn-on fluorescent chemosensors for silver ion based on nicotinonitriles, containing a tricyanobutadiene moiety (tricyanopyridine, TCPy) were developed. The enchantment of fluorescent emission can be observed by naked eye, even in the presence of interference cations. The binding mode turned out to be a 1: 1 ratio as determined using Job’s plot. ...
DOI:
10.1016/j.tetlet.2022.153819

3. 2,7-Diazapyrenes: a brief review on synthetic strategies and application opportunities

Author:
Anindita Mukherjee; Alexey A. Akulov; Sougata Santra; Mikhail V. Varaksin; Grigory A. Kim; Dmitry S. Kopchuk; Olga S. Taniya; Grigory V. Zyryanov; Oleg. N. Chupakhin
Source:
RSC advances 2022 v.12 no.15 pp. 9323-9341
ISSN:
2046-2069
Subject:
moieties,   etc   ; DNA; electronics; geometry;     Show all 4 Subjects
Abstract:
... 2,7-Diazapyrenes are promising azaaromatic scaffolds with a unique structural geometry and supramolecular properties. This core moiety and its derivatives with some N-methyl cations like N-methyl-2,7,-diazapyrenium, and N,N′-dimethyl-2,7-diazapyrenium attract special attention due to their challenging photophysical properties, especially in the context of interactions with DNA and some of its mono ...
DOI:
10.1039/d2ra00260d

4. Chiral rhodium(iii)–azobenzene complexes as photoswitchable DNA molecular locks

Author:
Mingwei Lin; Shanshan Zou; Tingzhen Li; Johannes Karges; Yu Chen; Yukun Zhao; Liangnian Ji; Hui Chao
Source:
Chemical communications 2022 v.58 no.27 pp. 4324-4327
ISSN:
1364-548X
Subject:
moieties,   etc   ; DNA; photoisomerization; rhodium;     Show all 4 Subjects
Abstract:
... Chiral rhodium(iii)–azobenzene complexes that are able to intercalate into DNA were developed. Upon light exposure, the azobenzene moiety of the metal complexes can photoisomerize from the trans-form to the cis-form, and strongly stabilize the DNA double-helix and modulate DNA transcription. This study presents the first example of metal-based photoswitchable DNA molecular locks. ...
DOI:
10.1039/d2cc00932c

5. Diastereo- and Enantioselective Synthesis of Borylated 3-Hydroxyoxindoles by Addition of gem-Diborylalkanes to Isatins

Author:
Yuan Zhou; Tong Xiong; Li-Yan Zhou; Hong-Yan Li; You-Cai Xiao; Fen-Er Chen
Source:
Organic letters 2022 v.24 no.2 pp. 791-796
ISSN:
1523-7052
Subject:
moieties,   etc   ; enantioselective synthesis; utilities;     Show all 3 Subjects
Abstract:
... The catalytic asymmetric synthesis of borylated 3-hydroxyoxindoles by addition of gem-diborylalkanes to isatins is disclosed. Chiral 3-hydroxyoxindoles bearing two contiguous stereogenic centers were produced in up to >20:1 dr and 99% ee. The synthetic utility of the corresponding products is presented through several transformations of the boryl moiety. This report provides an efficient strategy ...
DOI:
10.1021/acs.orglett.1c04380

6. Photoredox-Catalyzed Allylic Defluorinative Alkoxycarbonylation of Trifluoromethyl Alkenes through Intermolecular Alkoxycarbonyl Radical Addition

Author:
Jia-Xin Wang; Wei Ge; Ming-Chen Fu; Yao Fu
Source:
Organic letters 2022 v.24 no.7 pp. 1471-1475
ISSN:
1523-7052
Subject:
moieties,   etc   ; alcohols; alkenes; oxalates;     Show all 4 Subjects
Abstract:
... The gem-difluoroalkene moiety is an ideal carbonyl bioisostere in medicinal chemistry, but efficient synthesis of β-gem-difluoroalkene esters remains challenging so far. Herein, we disclose a photoredox-catalyzed allylic defluorinative alkoxycarbonylation of trifluoromethyl alkenes enabled by intermolecular alkoxycarbonyl radical addition. A wide variety of alcohol oxalate derivatives were amenabl ...
DOI:
10.1021/acs.orglett.1c04359

7. Porphyrins containing a tetraphenylethylene-substituted phenothiazine donor for fabricating efficient dye sensitized solar cells with high photovoltages

Author:
Jiazhi Zou; Yunyu Tang; Glib Baryshnikov; Zhen Yang; Rui Mao; Weifang Feng; Jian Guan; Chengjie Li; Yongshu Xie
Source:
Journal of materials chemistry A 2022 v.10 no.3 pp. 1320-1328
ISSN:
2050-7496
Subject:
moieties,   etc   ; dyes; phenothiazine; porphyrins;     Show all 4 Subjects
Abstract:
... With the aim to enhance the photovoltages and efficiencies of dye sensitized solar cells (DSSCs) based on porphyrin dyes, a dialkoxy-substituted highly twisted tetraphenylethylene (TPE) moiety has been introduced into the donor unit of a porphyrin dye to suppress dye aggregation and charge recombination. Thus, based on our previously reported porphyrin dye XW43, a dialkoxy-TPE moiety has been intr ...
DOI:
10.1039/d1ta09415g

8. Synthesis of 6,7-benzene-fused tropane derivatives from isoindoline-aminal hybrid compound

Author:
Tetsuya Tsujihara; Ryota Sasaki; Mizuki Fukkoshi; Sae Hatakeyama; Tsunayoshi Takehara; Takeyuki Suzuki; Tomikazu Kawano
Source:
Tetrahedron letters 2022 v.95 pp. 153724
ISSN:
0040-4039
Subject:
moieties,   etc   ; allylation; diastereoselectivity; skeleton;     Show all 4 Subjects
Abstract:
... Herein, the synthesis of 6,7-benzene-fused tropane derivatives from isoindoline-aminal hybrid compound has been reported. In the present synthetic study, ring-closing metathesis (RCM) was employed to construct the 6,7-benzene-fused tropene skeleton. To obtain the desired cis-1-allyl-3-stylylisoindoline precursor for the RCM reaction, the diastereoselective aza-Hosomi-Sakurai allylation and functio ...
DOI:
10.1016/j.tetlet.2022.153724

9. The galloyl moiety enhances inhibitory activity of polyphenols against adipogenic differentiation in 3T3-L1 preadipocytes

Author:
Jinming Peng; Wenjun Wen; Ruifeng Wang; Kaikai Li; Gengsheng Xiao; Chunmei Li
Source:
Food & function 2022 v.13 no.9 pp. 5275-5286
ISSN:
2042-650X
Subject:
moieties,   etc   ; adipocytes; adipogenesis; polyphenols;     Show all 4 Subjects
Abstract:
... Previous studies have proved that the characteristic galloyl moiety in polyphenols is crucial for their biological activities. However, whether the presence of the galloyl moiety in the structure of polyphenols has a great contribution to their inhibition of adipogenic differentiation is not clear. Therefore, in this study, seven polyphenols with different galloylation degrees were chosen for expl ...
DOI:
10.1039/d1fo04179g

10. [Co₂@(Ge₁₇Ni)]⁴⁻: the first edge-sharing double-cage endohedral germanide

Author:
Hong-Lei Xu; Lei Qiao; Zhong-Ming Sun
Source:
Chemical communications 2022 v.58 no.19 pp. 3190-3193
ISSN:
1364-548X
Subject:
moieties,   etc   ; chemical communication; models;     Show all 3 Subjects
Abstract:
... We report here a new double-cage endohedral Ge cluster, [Co₂@(Ge₁₇Ni)]⁴⁻, fused through two [Co@(Ge₉Ni)] moieties with a shared Ni–Ge edge. This ternary Co–Ge–Ni species not only represents the first double-cage example of an 18-vertex Zintl cluster, but also fills in the missing link of the edge fusion model in the double-cage systems. ...
DOI:
10.1039/d1cc06038d

11. 1,2-Acyl migration with α-imino rhodium carbenoids leading to substituted 1-naphthols

Author:
Tomoya Miura; Shunsuke Moritani; Yota Shiratori; Masahiro Murakami
Source:
Chemical communications 2022 v.58 no.16 pp. 2710-2713
ISSN:
1364-548X
Subject:
moieties,   etc   ; chemical communication; methodology; rhodium;     Show all 4 Subjects
Abstract:
... A unique method for the synthesis of substituted 1-naphthols by a rhodium(ii)-catalysed ring-expansion reaction of 2-triazolyl-1-indanone derivatives is reported. 1,2-Acyl migration occurs with an intermediate α-imino rhodium carbenoid generated from the triazolyl moiety. ...
DOI:
10.1039/d1cc06349a

12. An N-Fluorinated Imide for Practical Catalytic Imidations

Author:
Yuno Oe; Ryuhei Yoshida; Airi Tanaka; Akiya Adachi; Yuichiro Ishibashi; Takashi Okazoe; Kohsuke Aikawa; Takuya Hashimoto
Source:
Journal of the American Chemical Society 2022 v.144 no.5 pp. 2107-2113
ISSN:
1520-5126
Subject:
moieties,   etc   ; alkenes; benzene; derivatization; nitrogen;     Show all 5 Subjects
Abstract:
... Catalytic imidation using NFSI as the nitrogen source has become an emerging tool for oxidative carbon–nitrogen bond formation. However, the less than ideal benzenesulfonimide moiety is incorporated into products, severely detracting its synthetic value. As a solution to this challenge, we report herein the development of a novel N-fluorinated imide, N-fluoro-N-(fluorosulfonyl)carbamate (NFC), by ...
DOI:
10.1021/jacs.1c13569

13. Copper-catalyzed radical trifluoroethylthiolation of arylboronic acids with PhSO2SCH2CF3

Author:
Lefeng Dong; Junqing Liang; Ruijia Chen; Xiaoyong Xu; Xusheng Shao; Zhong Li
Source:
Tetrahedron letters 2022 v.92 pp. 153293
ISSN:
0040-4039
Subject:
moieties,   etc   ; agrochemicals; ambient temperature; clofibrate;     Show all 4 Subjects
Abstract:
... Trifluoroethylthio group (SCH₂CF₃) is a key functionality in several pharmaceutical and agrochemical compounds, the methods for the installation of the 2,2,2-trifluoroethylthio group are sought after. Herein, we report a copper-catalyzed trifluoroethylthiolation reaction of S-(2,2,2-trifluoroethyl) benzenesulfonothioates and phenylboronic acids at room temperature. The reaction achieved the insert ...
DOI:
10.1016/j.tetlet.2021.153293

14. Electrochemical-Oxidation-Promoted Direct N-ortho-Selective Difluoromethylation of Heterocyclic N-Oxides

Author:
Dong Zhang; Jinlin Cai; Jinze Du; Qingdong Wang; Jinming Yang; Rongqing Geng; Zheng Fang; Kai Guo
Source:
Organic letters 2022 v.24 no.7 pp. 1434-1438
ISSN:
1523-7052
Subject:
moieties,   etc   ; electrochemistry; hydrogen; quinoline; sodium;     Show all 5 Subjects
Abstract:
... An efficient and green electrochemical N-ortho-selective difluoromethylation method of various quinoline and isoquinoline N-oxides has been developed. In this method, sodium difluoromethanesulfinate (HCF₂SO₂Na) was used as the source of the difluoromethyl moiety, and various N-ortho-selective difluoromethylation quinoline and isoquinoline N-oxides were obtained in good to excellent yields under a ...
DOI:
10.1021/acs.orglett.1c04241

15. A radical–radical cross-coupling reaction of xanthene with sulfonyl hydrazides: facile access to xanthen-9-sulfone derivatives

Author:
Sumit Das; Shantonu Roy; Arup Bhowmik; Writhabrata Sarkar; Imtiaj Mondal; Aniket Mishra; Shubhra Jyoti Saha; Sudip Karmakar; Indubhusan Deb
Source:
Chemical communications 2022 v.58 no.17 pp. 2902-2905
ISSN:
1364-548X
Subject:
moieties,   etc   ; cross-coupling reactions; hydrazides; oxygen; xanthenes;     Show all 5 Subjects
Abstract:
... A straightforward strategy for direct incorporation of sulfonyl units into a xanthene moiety for accessing xanthen-9-sulfone derivatives in good to excellent yields has been established via metal-free radical–radical cross-coupling reaction of xanthenes and sulfonyl hydrazides. Using easily accessible starting materials, this methodology proceeds efficiently with a high degree of functional group ...
DOI:
10.1039/d1cc07143b

16. Deconstructive Insertion of Oximes into Coumarins: Modular Synthesis of Dihydrobenzofuran-Fused Pyridones

Author:
Ting-Yu Zheng; Yu-Qiang Zhou; Ning Yu; Yu-Lin Li; Tao Wei; Lan Peng; Yu Ling; Kun Jiang; Ye Wei
Source:
Organic letters 2022 v.24 no.12 pp. 2282-2287
ISSN:
1523-7052
Subject:
moieties,   etc   ; catalysts; coumarins; fluorescence; oximes; photoluminescence; pyridones;     Show all 7 Subjects
Abstract:
... In the presence of a copper catalyst, a series of oximes undergo deconstructive insertion into coumarins to afford structurally interesting dihydrobenzofuran-fused pyridones in moderate to good yields with good functional group compatibility. The reaction likely involves a radical relay annulation, leading to the ring opening of the lactone moiety of the coumarins, and simultaneous formation of th ...
DOI:
10.1021/acs.orglett.2c00384

17. Quantitative functionalization of chitosan using green and efficient azetidinium-amine reactions

Author:
Jyoti Devi Katiyar; Subrata Chattopadhyay
Source:
Carbohydrate polymers 2022 v.287 pp. 119324
ISSN:
0144-8617
Subject:
moieties,   etc   ; chitosan; hydrophilicity; hydrophobicity; molecular weight; solvents;     Show all 6 Subjects
Abstract:
... Despite significant advances in the field, quantitative post-polymer modification of chitosan, specifically attaching diverse hydrophobic moieties with experimentally predefined (via the ratio of reagents) degree of functionalization remain extremely challenging. In this context, we report our studies towards the use of green and efficient azetidinium-amine reactions to prepare a library of modifi ...
DOI:
10.1016/j.carbpol.2022.119324

18. Quinolizinium-based fluorescent probes for formaldehyde detection in aqueous solution, serum, and test strip via 2-aza-Cope rearrangement

Author:
Ajcharapan Tantipanjaporn; Karen Ka-Yan Kung; Hoi-Yi Sit; Man-Kin Wong
Source:
RSC advances 2022 v.12 no.18 pp. 11543-11547
ISSN:
2046-2069
Subject:
moieties,   etc   ; aqueous solutions; blood serum; fluorescence; formaldehyde;     Show all 5 Subjects
Abstract:
... Formaldehyde is an abundant contaminant in food and environments causing various diseases. Thus, the development of fast, simple, and selective formaldehyde detection is of great interest. Herein, novel quinolizinium-based fluorescent probes were designed based on a 2-aza-Cope rearrangement reaction and showed high selectivity to formaldehyde by fluorescence emission shift. We successfully reduced ...
DOI:
10.1039/d2ra01397e

19. Stereoselective construction of cycloheptene-fused indoline frameworks through photosensitised formal [5+2] cycloaddition

Author:
Noriyoshi Arai; Takeshi Ohkuma
Source:
Tetrahedron letters 2022 v.88 pp. 153588
ISSN:
0040-4039
Subject:
moieties,   etc   ; cycloaddition reactions; glass; irradiation; lamps; stereoselectivity;     Show all 6 Subjects
Abstract:
... Irradiation of 1-acylindole derivatives that possess a vinylcyclopropane moiety at the end of the acyl side chain by a high-pressure mercury lamp through Pyrex glass under sensitization of an aromatic ketone gave the corresponding cyclised products stereoselectively in high yields. The distribution of the products was highly dependent on the substituents on the cyclopropane ring. In the case of a ...
DOI:
10.1016/j.tetlet.2021.153588

20. Synthesis and Properties of V-Shaped Xanthene Dyes with Tunable and Predictable Absorption and Emission Wavelengths

Author:
Akari Yamagami; Kotaro Kiyotaki; Sae Wakabayashi; Naoki Egami; Kenichi Kawano; Shiroh Futaki; Ayumi Imayoshi; Kazunori Tsubaki
Source:
Journal of organic chemistry 2022 v.87 no.5 pp. 2336-2344
ISSN:
1520-6904
Subject:
moieties,   etc   ; absorption; energy; fluorescein; organic chemistry; xanthenes;     Show all 6 Subjects
Abstract:
... V-shaped xanthene dyes capable of predicting absorption and emission wavelengths are described. These dyes were synthesized by bridging a xanthene ring and an aryl moiety of fluorescein through ether covalent bonds. These dyes showed longer absorption and emission wavelengths than those of the parent fluorescein. Furthermore, substituents introduced on the aryl moiety mainly affected the lowest un ...
DOI:
10.1021/acs.joc.1c02139