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1. Emulsion templated scaffolds of poly(ε-caprolactone) – a review

Author:
Anilkumar Yadav; Sagnik Ghosh; Archana Samanta; Jit Pal; Rajiv K. Srivastava
Source:
Chemical communications 2022 v.58 no.10 pp. 1468-1480
ISSN:
1364-548X
Subject:
free radicals,   etc   ; emulsions; polymerization;     Show all 3 Subjects
Abstract:
... The role of poly(ε-caprolactone) (PCL) and its 3D scaffolds in tissue engineering has already been established due to its ease of processing into long-term degradable implants and approval from the FDA. This review presents the role of high internal phase emulsion (HIPE) templating in the fabrication of PCL scaffolds, and the versatility of the technique along with challenges associated with it. C ...
DOI:
10.1039/d1cc04941k

2. Catalyst-free addition/sulfonyl-assisted nucleophilic N–F hydrolysis of α-methylstyrenes with N,N-Difluorobenzenesulfonamides

Author:
Tao He; Xianjin Yang
Source:
Tetrahedron 2022 pp. 132863
ISSN:
0040-4020
Subject:
free radicals,   etc   ; Lewis bases; hydrolysis; synergism;     Show all 4 Subjects
Abstract:
... The catalyst-free addition of N,N-difluorobenzenesulfonamides (DFBSA) with α-methylstyrenes and the in-situ-N–F bond hydrolysis of the adducts were accomplished. N-fluoro-N-hydroxy-β-amine ethyl sulfonyl derivatives were obtained in moderate yields, particularly, the water needed for hydrolysis originated from the reaction system without additional supply. The results of several control experiment ...
DOI:
10.1016/j.tet.2022.132863

3. Free Radical Cascade Carbochloromethylations of Activated Alkenes

Author:
Zhi-Wei Zhao; Yu-Song Ran; Yu-Jian Hou; Xin Chen; Xue-Ling Ding; Cui Zhang; Ya-Min Li
Source:
Journal of organic chemistry 2022 v.87 no.6 pp. 4183-4194
ISSN:
1520-6904
Subject:
free radicals,   etc   ; acrylamides; alkenes; organic chemistry;     Show all 4 Subjects
Abstract:
... Free radical carbochloromethylations of ortho-cyanoarylacrylamides and N-(arylsulfonyl)acrylamides have been developed by employing simple alkyl chlorides as the chloromethyl source. The transformations are characterized by wide functional group compatibility and utilizing readily available reagents, thus providing efficient methods for constructing polychloromethyl-substituted quinoline-2,4-dione ...
DOI:
10.1021/acs.joc.1c03024

4. Ligand-Promoted Nickel-Catalyzed para-Selective Carboxylation of Anisoles

Author:
Guangliang Tu; Guodong Ju; Shun-Jun Ji; Yingsheng Zhao
Source:
Organic letters 2022 v.24 no.11 pp. 2155-2159
ISSN:
1523-7052
Subject:
free radicals,   etc   ; benzene; carboxylation; catalysts; nickel;     Show all 5 Subjects
Abstract:
... It has always been a challenge in free radical chemistry to control site selectivity during the reaction of free radicals with aromatic rings. Herein, we report the site-selective carboxylation of anisoles through the direct reaction of the bromoform radical with a benzene ring at the para position under the assistance of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline with nickel(II) as the catalys ...
DOI:
10.1021/acs.orglett.2c00417

5. Cyclic poly(β-amino ester)s with enhanced gene transfection activity synthesized through intra-molecular cyclization

Author:
Chenfei Wang; Xiaobei Huang; Litao Sun; Qiuxia Li; Zhili Li; Haiyang Yong; Delu Che; Cong Yan; Songmei Geng; Wenxin Wang; Dezhong Zhou
Source:
Chemical communications 2022 v.58 no.13 pp. 2136-2139
ISSN:
1364-548X
Subject:
free radicals,   etc   ; chemical reactions; genes; topology; transfection;     Show all 5 Subjects
Abstract:
... Topological structure plays a critical role in gene delivery of cationic polymers. Cyclic poly(β-amino ester)s (CPAEs) are successfully synthesized via sequential Michael addition and free radical initiating ring-closure reaction. The CPAEs exhibit superior gene transfection efficiency and safety profile compared to their linear counterparts. ...
DOI:
10.1039/d1cc06480k

6. Disentangling the Puzzling Regiochemistry of Thiol Addition to o-Quinones

Author:
Maria L. Alfieri; Alice Cariola; Lucia Panzella; Alessandra Napolitano; Marco d’Ischia; Luca Valgimigli; Orlando Crescenzi
Source:
Journal of organic chemistry 2022 v.87 no.7 pp. 4580-4589
ISSN:
1520-6904
Subject:
free radicals,   etc   ; cysteine; glutathione; organic chemistry; thiols;     Show all 5 Subjects
Abstract:
... The addition of thiol compounds to o-quinones, as exemplified by the biologically relevant conjugation of cysteine to dopaquinone, displays an anomalous 1,6-type regiochemistry compared to the usual 1,4-nucleophilic addition, for example, by amines, which has so far eluded intensive investigations. By means of an integrated experimental and computational approach, herein, we provide evidence that ...
DOI:
10.1021/acs.joc.1c02911

7. Molecularly imprinted polymers via reversible addition–fragmentation chain-transfer synthesis in sensing and environmental applications

Author:
Irvin Veloz Martínez; Jackeline Iturbe Ek; Ethan C. Ahn; Alan O. Sustaita
Source:
RSC advances 2022 v.12 no.15 pp. 9186-9201
ISSN:
2046-2069
Subject:
free radicals,   etc   ; molecular imprinting; polymerization; polymers; sorption;     Show all 5 Subjects
Abstract:
... Molecularly imprinted polymers (MIP) have shown their potential as artificial and selective receptors for environmental monitoring. These materials can be tailor-made to achieve a specific binding event with a template through a chosen mechanism. They are capable of emulating the recognition capacity of biological receptors with superior stability and versatility of integration in sensing platform ...
DOI:
10.1039/d2ra00232a

8. 2-methoxy-4-(((5-nitropyridin-2-yl)imino)methyl)phenol Schiff base ligand and its Cu(II) and Zn(II) complexes: synthesis, characterization and biological investigations

Author:
P. Deepika; H.M. Vinusha; Muneera Begum; Ramith Ramu; Prithvi S. Shirahatti; M.N. Nagendra Prasad
Source:
Heliyon 2022 v.8 no.6 pp. e09648
ISSN:
2405-8440
Subject:
free radicals,   etc   ; ligands; schiff bases; stoichiometry; thermogravimetry; vanillin;     Show all 6 Subjects
Abstract:
... In this current work we have prepared a Schiff base ligand, (HL) derived from 5- nitropyridine-2-amine with 4-hydroxy-3-methoxybenzaldehyde and its Cu(II), and Zn(II) in 2:1 stoichiometric ratio (2HL:M). The formation of the ligand and the metal complexes were evaluated by means of MS, FT-IR, UV-Visible, ¹H-NMR, ¹³C-NMR and thermogravimetric methods. The free radical scavenging activity of compoun ...
DOI:
10.1016/j.heliyon.2022.e09648

9. Bioinspired Cobalt-Catalysis Enables Generation of Nucleophilic Radicals from Oxetanes

Author:
Aleksandra Potrząsaj; Michał Ociepa; Wojciech Chaładaj; Dorota Gryko
Source:
Organic letters 2022 v.24 no.13 pp. 2469-2473
ISSN:
1523-7052
Subject:
free radicals,   etc   ; Lewis bases; complement; regioselectivity; transition elements;     Show all 5 Subjects
Abstract:
... Oxetanes are valuable building blocks due to their well-explored propensity to undergo ring-opening reactions with nucleophiles. However, their application as precursors of radical species is still elusive. Herein, we present a bioinspired cobalt-catalysis-based strategy to access unprecedented modes of radical reactivity via oxetane ring-opening. This powerful approach gives access to nucleophili ...
DOI:
10.1021/acs.orglett.2c00355

10. Free Radical Promoted Trifluoromethylthiolation of Alkynes to Access SCF₃-Containing Dibenzazepines or Dioxodibenzothiazepines

Author:
Yingming Ren; Qinqin Yan; Yang Li; Yongjun Gao; Jincan Zhao; Lijun Li; Zhong-Quan Liu; Zejiang Li
Source:
Journal of organic chemistry 2022 v.87 no.13 pp. 8773-8781
ISSN:
1520-6904
Subject:
free radicals,   etc   ; X-ray diffraction; alkynes; organic chemistry;     Show all 4 Subjects
Abstract:
... Persulfate-promoted radical cascade trifluoromethylthiolation of aryl acetylenes with AgSCF₃ provides a simple reaction system for the synthesis of SCF₃-substituted dibenzazepines or dioxodibenzothiazepines with good Z/E selectivity. The single-crystal X-ray diffraction data confirms the structures of the final products. A series of scaled-up experiments, further transformations, and radical inhib ...
DOI:
10.1021/acs.joc.2c00623

11. Non-innocent redox behavior of Cuᴵᴵ–p-dimethylaminophenolate complexes: formation and characterization of the Cuᴵ–phenoxyl radical species

Author:
Yuto Shima; Takashi Suzuki; Hitoshi Abe; Tatsuo Yajima; Seiji Mori; Yuichi Shimazaki
Source:
Chemical communications 2022 v.58 no.44 pp. 6401-6404
ISSN:
1364-548X
Subject:
free radicals,   etc   ; chemical communication; gases; ions; ligands; solvents;     Show all 6 Subjects
Abstract:
... Cu complexes with p-dimethylaminophenolate ligands were synthesized by the reaction of Cuᴵᴵ ions with the ligands under inert gas atmosphere and characterized. The complexes showed a valence state change from Cuᴵᴵ–phenolate to Cuᴵ–phenoxyl radical on loss of the coordinated solvent. The Cuᴵ–phenoxyl radical species showed the characteristic properties and reactivities. ...
DOI:
10.1039/d2cc01409b

12. Visible-light induced synthesis of 8H-indolo[3,2,1-de]phenanthridin-8-ones and related heterocycles using benzothiadiazole as photocatalyst

Author:
Li Qiao; Ke Zhang; Hanjie Li; Ping Lu; Yanguang Wang
Source:
Tetrahedron letters 2022 v.91 pp. 153648
ISSN:
0040-4039
Subject:
free radicals,   etc   ; cyclization reactions; fluorescence; heterocyclic compounds; photocatalysts;     Show all 5 Subjects
Abstract:
... A simple and mild approach to access polycyclic 8H-indolo[3,2,1-de]phenanthridin-8-ones through a visible-light induced free radical cyclization of (2-bromophenyl)(9H-carbazol-9-yl)methanones using benzothiadiazole-containing photocatalyst is reported. This transition metal free method can be utilized for the synthesis of 7H-thieno[2′,3′:4,5]pyrido[3,2,1-jk]carbazol-7-one, 14H-isoquinolino[4,3,2-k ...
DOI:
10.1016/j.tetlet.2022.153648

13. Copper(II)-Catalyzed Direct C–H Trifluoroethylation of Heteroarenes

Author:
Lefeng Dong; Tingting Feng; Dongdong Xiong; Zhiping Xu; Jiagao Cheng; Xiaoyong Xu; Xusheng Shao; Zhong Li
Source:
Organic letters 2022 v.24 no.10 pp. 1913-1917
ISSN:
1523-7052
Subject:
free radicals,   etc   ; application methods; bioactive compounds; drugs; exhibitions; methodology;     Show all 6 Subjects
Abstract:
... Trifluoroethyl (CH₂CF₃) is an important functional group in many pharmaceutical and agrochemical compounds. Herein, we report an efficient method for the copper-catalyzed direct trifluoroethylation of heteroarenes. The reaction exhibited good compatibility to various substrates, and the desired products were obtained in good yields. Preliminary mechanistic investigations indicate the trifluoroethy ...
DOI:
10.1021/acs.orglett.2c00245

14. Insight into the catalytic performance of silver oxides towards peroxymonosulfate activation for pollutants degradation: Efficiency, mechanism and stability

Author:
Xinchao Ruan; Siji Zhou; Chuankun Yin; Jiale Bai; Xuewen Zhang; Aimal Khan; Aihua Xu; Xiaoxia Li
Source:
Colloids and surfaces 2022 v.642 pp. 128674
ISSN:
0927-7757
Subject:
free radicals,   etc   ; catalytic activity; oxidation; p-nitrophenol; silver; wastewater;     Show all 6 Subjects
Abstract:
... Silver-based materials have emerged as excellent catalysts for peroxymonosulfate (PMS) activation in wastewater pollutants degradation. However, the mechanism of pure silver oxides towards PMS activation remains insufficient. In this work, Ag₂O and AgO were selected as typical silver oxides to detect the catalytic performance. AgO/PMS possessed higher activity for p-nitrophenol and other pollutant ...
DOI:
10.1016/j.colsurfa.2022.128674

15. Preparation and Characterization of Thermoresponsive Poly(N-vinylisobutyramide) Microgels

Author:
Hiroaki Yoshida; Hiroya Furumai; Hiroharu Ajiro
Source:
Langmuir 2022 v.38 no.17 pp. 5269-5274
ISSN:
1520-5827
Subject:
free radicals,   etc   ; hydrogels; hydrolysis; microgels; polymerization; sodium dodecyl sulfate;     Show all 6 Subjects
Abstract:
... Microgels are soft, adaptive materials exhibiting various properties not only like hydrogels and microparticles but also like macromolecules, colloids, and surfactants. To widen the range of their biomedical and environmental applications, the exploration of an alternative for poly(N-alkylacrylamide)s without potential safety risks is of great importance. In this article, thermoresponsive poly(N-v ...
DOI:
10.1021/acs.langmuir.1c02676

16. Synthesis of Acyl Hydrazides via a Radical Chemistry of Azocarboxylic tert-Butyl Esters

Author:
Hong-Xia Zhang; Rui-Li Guo; Xing-Long Zhang; Meng-Yue Wang; Bao-Yin Zhao; Ya-Ru Gao; Qiong Jia; Yong-Qiang Wang
Source:
Journal of organic chemistry 2022 v.87 no.10 pp. 6573-6587
ISSN:
1520-6904
Subject:
free radicals,   etc   ; azo compounds; esters; hydrazides; journals; organic chemistry;     Show all 6 Subjects
Abstract:
... A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in func ...
DOI:
10.1021/acs.joc.2c00139

17. Synthesis, characterization, and biological evaluation of novel selenium-containing chitosan derivatives

Author:
Wanwen Chen; Hao Cheng; Lingyun Chen; Xiaobei Zhan; Wenshui Xia
Source:
Carbohydrate polymers 2022 v.284 pp. 119185
ISSN:
0144-8617
Subject:
free radicals,   etc   ; antineoplastic activity; biological assessment; chitosan; esterification; selenium;     Show all 6 Subjects
Abstract:
... Though great efforts have been made to develop selenium polysaccharides with unique properties using HNO₃-Na₂SeO₃ methods, the Se content is still low due to the poor esterification efficiency of H₂SeO₃. Herein, selenodiacetic acid (SA) was introduced into chitosan (CS) to synthesize O-selenodiacetyl chitosan (OSAC) and chitosan-ammonium selenodiacetate (CASA) by covalent and non-covalent interact ...
DOI:
10.1016/j.carbpol.2022.119185

18. Active sites of peptides Asp-Asp-Asp-Tyr and Asp-Tyr-Asp-Asp protect against cellular oxidative stress

Author:
Huifan Liu; Jiaxi Liang; Gengsheng Xiao; Celia Vargas-De-La-Cruz; Jesus Simal-Gandara; Jianbo Xiao; Qin Wang
Source:
Food chemistry 2022 v.366 pp. 130626
ISSN:
0308-8146
Subject:
free radicals,   etc   ; antioxidant activity; energy; food chemistry; oxidative stress; peptides;     Show all 6 Subjects
Abstract:
... The protective effects of the peptides Asp-Asp-Asp-Tyr (DDDY) and Asp-Tyr-Asp-Asp (DYDD) against AAPH-induced HepG2 cells are unclear. Our objective was to investigate the active sites of these peptides and their cellular antioxidant mechanism. DDDY and DYDD show a direct free radical scavenging effect in reducing ROS levels and maintained cellular antioxidant enzymes at normal levels. The quantum ...
DOI:
10.1016/j.foodchem.2021.130626

19. Development and microbial characterization of Bio-RD-PAOP for effective remediation of polychlorinated biphenyls

Author:
Rifeng Wu; Shangwei Zhang; Shanquan Wang
Source:
Journal of hazardous materials 2022 v.436 pp. 129190
ISSN:
0304-3894
Subject:
free radicals,   etc   ; Dehalococcoides; biofilm; chlorine; dechlorination; mineralization; oxidation; remediation; sulfates;     Show all 9 Subjects
Abstract:
... Polychlorinated biphenyls (PCBs) as typical halogenated persistent organic pollutants are widely distributed in natural environments, and can be enriched and magnified in organisms via food webs. It is consequently urgent and necessary to develop techniques to completely remove these persistent organohalides. In this study, we developed a process (Bio-RD-PAOP) by integrating microbial reductive de ...
DOI:
10.1016/j.jhazmat.2022.129190

20. A free radical relay combustion approach to scramjet ignition at a low Mach number

Author:
Haoqiang Sheng; Yuan Ji; Xiaobin Huang; Zhengchuang Zhao; Wenbin Hu; Junming Chen; Hong Liu
Source:
Energy 2022 v.247 pp. 123539
ISSN:
0360-5442
Subject:
free radicals,   etc   ; catalytic activity; combustion; droplets; energy; evaporation; hydrogen; kerosene; temperature;     Show all 9 Subjects
Abstract:
... Turbine-based combined cycle (TBCC) engines, which consist of turbine and scramjet engines, are a key power system for the acceleration, powered horizontal landing, and reuse of hypersonic vehicles. Low Mach number ignition of kerosene-based scramjet fuel is expected to enable the practical application of TBCC engines. However, ignition under these conditions is extremely difficult to achieve. In ...
DOI:
10.1016/j.energy.2022.123539