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1. The formation of PBDFs from the ortho-disubstituted phenol precursors: A comprehensive theoretical study on the PBDD/Fs formation from 2,4,6-tribromophenol

Author:
Chang, Jiamin; Pan, Wenxiao; Liu, Xian; Xue, Qiao; Fu, Jianjie; Zhang, Aiqian
Source:
The Science of the total environment 2020 v.713 pp. 136657
ISSN:
0048-9697
Subject:
phenol,   etc   ; bromination; dibenzofuran; thermodynamics; toxicity;     Show all 5 Subjects
Abstract:
... Bromophenols are known as direct precursors of the notorious polybrominated dibenzo-p-dioxin/dibenzofurans (PBDD/Fs). There is a long-held viewpoint that only the more toxic dioxin-type products could be formed from the ortho-disubstituted phenols, totally contrary to the experimental observations that both PBDDs and PBDFs are generated. To tackle the issue, the gaseous formation mechanism of PBDD ...
DOI:
10.1016/j.scitotenv.2020.136657

2. Practical way for the synthesis of 4H-benzo[e][1,3]oxazine by anhydride-promoted [4+2] cyclization of in situ generated o-quinone methides with amides

Author:
Zhang, Lei; Shi, Min; Wang, Feijun
Source:
Tetrahedron letters 2020 v.61 no.23 pp. 151965
ISSN:
0040-4039
Subject:
phenols,   etc   ; amides; chemical reactions; chemical structure; quinones;     Show all 5 Subjects
Abstract:
... An anhydride-promoted [4+2] cyclization of easily available 2-(hydroxymethyl)phenols with amides was reported, providing a practical way to the synthesis of novel highly steric 3,3′-bis-substituted 4H-benzo[e][1,3]oxazines as well as bis(benzo[e][1,3]oxazines). ...
DOI:
10.1016/j.tetlet.2020.151965

3. Thermal [2 + 2]-cycloaddition between silylalkynes and allenylphenols followed by the nucleophilic addition of water: metal-free and economical synthesis of arylcyclobutenals

Author:
Ohno, Shohei; Avena, Ramon Francisco; Aoyama, Hiroshi; Fujioka, Hiromichi; Arisawa, Mitsuhiro
Source:
Green chemistry 2020 v.22 no.4 pp. 1220-1228
ISSN:
1463-9270
Subject:
phenols,   etc   ; Lewis bases; alkynes; green chemistry;     Show all 4 Subjects
Abstract:
... Herein, we report an unprecedented thermal [2 + 2]-cycloaddition between silylalkynes and allenylphenols to form an aromatizing cyclobutachromene intermediate, followed by the nucleophilic addition of water to yield functionalized arylcyclobutenals. This reaction is atom- and pot-economical because all the atoms contained in the starting material are retained in the final product, no other reactan ...
DOI:
10.1039/c9gc04184b

4. Concise Formal Synthesis of the Pseudopterosins via Anionic Oxy-Cope/Transannular Michael Addition Cascade

Author:
Ramella, Vincenzo; Roosen, Philipp C.; Vanderwal, Christopher D.
Source:
Organic letters 2020 v.22 no.8 pp. 2883-2886
ISSN:
1523-7052
Subject:
phenol,   etc   ; carbon; chemical structure; cycloaddition reactions; oxidation;     Show all 5 Subjects
Abstract:
... An anionic oxy-Cope/transannular Michael addition cascade converts a spirocyclic architecture—readily available by Diels–Alder cycloaddition—into the hydrophenalene carbon skeleton of the pseudopterosin aglycones. Oxidation of the resulting cyclohexenone ring to the phenol that is characteristic of the targets completes a short formal synthesis. ...
DOI:
10.1021/acs.orglett.0c00486

5. SNAr azidation of phenolic functions utilizing diphenyl phosphorazidate

Author:
Ishihara, Kotaro; Shioiri, Takayuki; Matsugi, Masato
Source:
Tetrahedron letters 2020 v.61 no.7 pp. 151493
ISSN:
0040-4039
Subject:
phenol,   etc   ; azides; chemical reactions; chemical structure;     Show all 4 Subjects
Abstract:
... A useful method for the synthesis of aryl azides via SNAr reaction of phenol derivatives using diphenyl phosphorazidate (DPPA) as an azidation reagent was developed. Various phenol derivatives bearing electron-withdrawing groups were converted into the corresponding aryl azides in a single step. This method is easy to perform and enables the preparation of aryl azides without the use of explosive ...
DOI:
10.1016/j.tetlet.2019.151493

6. Difluoroboron-Enabled Thermally Activated Delayed Fluorescence

Author:
Li, Guijie; Lou, Weiwei; Wang, Dan; Deng, Chao; Zhang, Qisheng
Source:
ACS applied materials & interfaces 2019 v.11 no.35 pp. 32209-32217
ISSN:
1944-8252
Subject:
phenols,   etc   ; fluorescence; moieties; photoluminescence;     Show all 4 Subjects
Abstract:
... A new series of tetracoordinated boron-enabled thermally activated delayed fluorescence (TADF) materials with a donor–acceptor BF₂-type framework were designed and conveniently synthesized. Difluoroboron plays a critical role and acts as a key to coordinate with the latent acceptor of the 2-(4-phenylpyridin-2-yl)phenol (PPyPOH) moiety to realize TADF. TADF materials are air-stable and have a high ...
DOI:
10.1021/acsami.9b08107

7. Regioselective synthesis of gentisyl alcohol-type marine natural products

Author:
Wang, Hong-Shuang; Li, Hui-Jing; Wang, Long-Fei; Shen, Zhi-Lun; Wu, Yan-Chao
Source:
Natural product research 2019 v.33 no.13 pp. 1891-1896
ISSN:
1478-6427
Subject:
phenol,   etc   ; dithionite; oxidation; regioselectivity;     Show all 4 Subjects
Abstract:
... Gentisyl alcohol-type natural products, possessing various important biological properties, have been synthesized from 4-methoxyphenol by using a selective phenol monohydroxymethylation/monochlorination, a CAN oxidation and a sodium dithionite reduction as the key steps. The natural product synthesis is efficient, atom- and step-economical, and requires no protecting groups. ...
DOI:
10.1080/14786419.2018.1478831

8. Mechanism of the temperature-responsive material regulating porous morphology on epoxy phenolic novolac resin microcapsule surface

Author:
Zhang, Xianpeng; Zhang, Luxia; Zhang, Daxia; Liu, Sisi; Wei, Dengguo; Liu, Feng
Source:
Colloids and surfaces 2020 v.593 pp. 124581
ISSN:
0927-7757
Subject:
phenols,   etc   ; encapsulation; epoxides; lipophilicity; solubility; strength (mechanics); surface area; temperature;     Show all 8 Subjects
Abstract:
... Porous microcapsules (MCs) with tailorable surface morphology are indispensable in practical applications because of their large surface area and controlled release. In this study, epoxy phenolic novolac resin MCs were prepared with temperature-responsive 2,4,6-tris(dimethylaminomethyl)phenol (DMP) as crosslinker. Reaction temperature was proved to generate distinct effects on MC porous morphology ...
DOI:
10.1016/j.colsurfa.2020.124581

9. Synthesis of α-Aryl Oxindoles by Friedel–Crafts Alkylation of Arenes

Author:
Rokade, Balaji V.; Guiry, Patrick J.
Source:
Journal of organic chemistry 2020 v.85 no.9 pp. 6172-6180
ISSN:
1520-6904
Subject:
phenols,   etc   ; alkylation; allylation; benzene; moieties; organic chemistry; protonation; solvents;     Show all 8 Subjects
Abstract:
... α-Aryl oxindoles are accessed from isatin via a two-step procedure involving a phospha-Brook rearrangement and a Friedel–Crafts alkylation in a one-pot procedure. The use of 1,1,1,3,3,3-hexafluoro-2-propanol as solvent significantly extended the reaction substrate scope to include relatively less electron-rich arenes including benzene. This new alkylation method is fast and straightforward and all ...
DOI:
10.1021/acs.joc.0c00370

10. Correction to: a new Rhodococcus aetherivorans strain isolated from lubricant-contaminated soil as a prospective phenol-biodegrading agent

Author:
Nogina, Taisiya; Fomina, Marina; Dumanskaya, Tatiana; Zelena, Liubov; Khomenko, Lyudmila; Mikhalovsky, Sergey; Podgorskyi, Valentin; Gadd, Geoffrey Michael
Source:
Applied microbiology and biotechnology 2020 v.104 no.8 pp. 3689-3690
ISSN:
0175-7598
Subject:
phenols,   etc   ; Rhodococcus aetherovorans; biodegradation; polluted soils; soil pollution;     Show all 5 Subjects
Abstract:
... The published online version contains mistake in Table 3. ...
DOI:
10.1007/s00253-020-10489-z

11. Vanadium-Catalyzed Oxidative Intramolecular Coupling of Tethered Phenols: Formation of Phenol-Dienone Products

Author:
Gilmartin, Philip H.; Kozlowski, Marisa C.
Source:
Organic letters 2020 v.22 no.8 pp. 2914-2919
ISSN:
1523-7052
Subject:
phenol,   etc   ; alkaloids; catalysts; catalytic activity; chemical reactions; chemical structure;     Show all 6 Subjects
Abstract:
... A mild and efficient method for the vanadium-catalyzed intramolecular coupling of tethered free phenols is described. The corresponding phenol-dienone products are prepared directly in good yields with low catalyst loadings. Electronically diverse tethered phenol precursors are well tolerated, and the catalytic method was effectively applied as the key step in syntheses of three natural products a ...
DOI:
10.1021/acs.orglett.0c00577

12. Synthesis of Triarylmethanes by Decarbonylation of 3,3-Diaryl Benzofuranones

Author:
Tang, Zhi; Peng, Lingteng; Yuan, Yu; Li, Tianjing; Qiu, Renhua; Kambe, Nobuaki
Source:
Journal of organic chemistry 2020 v.85 no.8 pp. 5300-5311
ISSN:
1520-6904
Subject:
phenol,   etc   ; arylation; dimethylformamide; heat; heterocyclic compounds; moieties; organic chemistry;     Show all 7 Subjects
Abstract:
... A simple protocol for the synthesis of triarylmethane derivatives with three different (hetero)aryl groups by decarbonylation of 3,3-diaryl benzofuranones, which can easily be prepared via arylation of benzofuranones, was developed. The reaction proceeds on heating in dimethylformamide (DMF) in the presence of CH₃ONa and water to generate the products in good to excellent yields. This reaction can ...
DOI:
10.1021/acs.joc.9b03433

13. Stereoselective synthesis of para-quinone monoketals through tri-bromide (TBr) mediated oxidative dearomatization of phenols

Author:
Sahoo, Sushree Ranjan; Sarkar, Debayan
Source:
Tetrahedron letters 2020 v.61 no.12 pp. 151646
ISSN:
0040-4039
Subject:
phenols,   etc   ; chemical reactions; chemical structure; hydrogen; palladium; quinones; stereoselective synthesis;     Show all 7 Subjects
Abstract:
... A metal free one-pot stereoselective synthesis of para-quinone monoketals and their derivatives has been reported in this present work. Tri-bromides (TBrs) have been employed as an effective reagent for intramolecular spirocyclizations leading to excellent yields of the monoketals. The TBrs are slowly turning out to be an important reagent for oxidative dearomatization which is further attested in ...
DOI:
10.1016/j.tetlet.2020.151646

14. M[TPP]Cl (M = Fe or Mn)-Catalyzed Oxidative Amination of Phenols by Primary and Secondary Anilines

Author:
Vershinin, Vlada; Pappo, Doron
Source:
Organic letters 2020 v.22 no.5 pp. 1941-1946
ISSN:
1523-7052
Subject:
phenols,   etc   ; amination; benzoquinones; catalytic activity; chemical structure; dehydrogenation; iron; manganese;     Show all 8 Subjects
Abstract:
... Iron- and manganese-catalyzed para-selective oxidative amination of (4-R)phenols by primary and secondary anilines was developed. Depending on the identity of the R group, the products of this efficient reaction are either benzoquinone anils (C–N coupling) that are produced via a sequential oxidative amination/dehydrogenation (R = H), oxidative amination/elimination (R = OMe) steps, or N,O-biaryl ...
DOI:
10.1021/acs.orglett.0c00296

15. FeCl3 catalyzed 1,6-conjugate addition of phenol C-nucleophiles: Facile synthesis of diarylmethanes

Author:
Sreenivas, Kukkamudi; Khan, Faiz Ahmed
Source:
Tetrahedron 2020 v.76 no.6 pp. 130885
ISSN:
0040-4020
Subject:
phenol,   etc   ; aromatization; catalytic activity; ferric chloride; moieties; quinones;     Show all 6 Subjects
Abstract:
... An efficient synthesis of diarylmethane derivatives from phenol and a p-quinone methide surrogate cyclohexadienone derivative has been described. This 1,6-conjugate addition reaction is catalyzed by earth abundant FeCl₃ and it proceeds via a consecutive Michael type addition followed by aromatization. Various proportions of phenol and cyclohexadienone produced exclusively mono, bis and tris additi ...
DOI:
10.1016/j.tet.2019.130885

16. Enhancing thermal properties of polybenzoxazine by incorporation of 4-cyanophenol

Author:
Zhu, Yongfei; Su, Junming; Lin, Runsheng; Jiang, Yuhua; Li, Peilin
Source:
Thermochimica acta 2020 v.683 pp. 178465
ISSN:
0040-6031
Subject:
phenol,   etc   ; carbon dioxide; polymerization; thermal degradation; thermal properties; volatilization;     Show all 6 Subjects
Abstract:
... In order to study the effect of strong electron-withdrawing group on thermal properties of polybenzoxazine, 4-cyanophenol-based benzoxazines were prepared and their cured samples were investigated by FTIR, TGA, TGA-FTIR, Py-GC–MS and LOI tests. FTIR results indicate that nitrile group hardly polymerized and existed in polybenzoxazine at present cured conditions. TGA results show that the introduct ...
DOI:
10.1016/j.tca.2019.178465

17. Kinetics of PMS activation by graphene oxide and biochar

Author:
Wang, Shizong; Wang, Jianlong
Source:
Chemosphere 2020 v.239 pp. 124812
ISSN:
0045-6535
Subject:
phenol,   etc   ; adsorption; biochar; carbon; catalysts; graphene oxide; kinetics; moieties; pollutants;     Show all 9 Subjects
Abstract:
... Carbon-based materials have been studied as metal-free catalyst for persulfate activation. At present, the activation performance of carbon materials for persulfate is usually characterized by the removal efficiency of organic pollutants. However, the kinetics of persulfate activation by carbon materials has not been investigated. In this study, the kinetics of peroxymonosulfate (PMS) activation b ...
DOI:
10.1016/j.chemosphere.2019.124812

18. DFT Analysis of the Adsorption of Phenol on the Nonpolar (101̅0) ZnO Surface

Author:
Maldonado, Frank; Villamagua, Luis; Rivera, Richard
Source:
Journal of physical chemistry 2019 v.123 no.19 pp. 12296-12304
ISSN:
1932-7455
Subject:
phenol,   etc   ; adsorption; oxygen; zinc oxide;     Show all 4 Subjects
Abstract:
... In this work, a study of the molecular adsorption and geometry of phenol on the nonpolar (101̅0) ZnO surface has been carried out. In an attempt to reproduce a more realistic system, an oxygen vacancy has been introduced in the surface, which leads to an increase in the band gap, from 1.16 eV for the pristine surface to 1.38 eV in the defective one, and a local level within the band gap, which cor ...
DOI:
10.1021/acs.jpcc.9b01906

19. De novo synthesis of Cr-embedded MOF-199 and derived porous CuO/CuCr₂O₄ composites for enhanced phenol hydroxylation

Author:
Huang, Yu-Yuan; Konnerth, Hannelore; Yeh, Jyun-Yi; Prechtl, Martin H. G.; Wen, Cheng-Yen; Wu, Kevin C.-W.
Source:
Green chemistry 2019 v.21 no.8 pp. 1889-1894
ISSN:
1463-9270
Subject:
phenol,   etc   ; green chemistry; hydroxylation; oxides;     Show all 4 Subjects
Abstract:
... A de novo synthesis of Cr-embedded MOF-199 was developed for the first time. This Cr-MOF-199 material was further derived into CuO/CuCr₂O₄ composites with a porous and uniform structure. The obtained bimetallic oxides with a porous structure were further applied in phenol hydroxylation. ...
DOI:
10.1039/c8gc03348j

20. Polyphenol oxidase browning in the formation of dark spots on fresh wet noodle sheets: How dark spots formed

Author:
Zhao, Yang; Huang, Ze-Hua; Zhou, Hui-Ming; Zhu, Ke-Xue; Guo, Xiao-Na; Peng, Wei
Source:
Food chemistry 2020 v.329 pp. 126800
ISSN:
0308-8146
Subject:
phenol,   etc   ; catalytic activity; catechol oxidase; chemical composition; color; dehydrogenation; melanin; noodles; pH; polymerization; polyphenols;     Show all 11 Subjects
Abstract:
... The role of polyphenol oxidase (PPO) in the browning of fresh wet noodle sheets (FWNS) was discussed. To release the chemical formation mechanism of the dark spots formed on FWNS, the reconstituted FWNS and PPO-catechol reaction systems were prepared. Different from the overall color change of FWNS, almost all the melanins in dark spots were indirect products of PPO catalysis. The PPO catalytic de ...
DOI:
10.1016/j.foodchem.2020.126800