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You searched for: Subject "tetrahydrofuran" Remove constraint Subject: "tetrahydrofuran"
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1. Interfacial mechanical properties of tetrahydrofuran hydrate-solid surfaces: Implications for hydrate management

Author:
Yanwen Lin; Tong Li; Senyun Liu; Qiao Shi; Ke Xu; Zhisen Zhang; Jianyang Wu
Source:
Journal of colloid and interface science 2023 v.629 pp. 326-335
ISSN:
0021-9797
Subject:
tetrahydrofuran,   etc   ; adhesion; contact angle; glass; ice; molecular dynamics; polymers; silanes; silica; temperature; thiols; wettability;     Show all 12 Subjects
Abstract:
... Understanding the interfacial mechanical properties between hydrate and solids is vital to designing and fabricating surfaces for hydrate management. Herein, the role of the surface wettability, the type of solid substrate and temperature on the interfacial adhesion properties of tetrahydrofuran (THF) hydrate and ice were examined by force analysis based shearing measurements and molecular dynamic ...
DOI:
10.1016/j.jcis.2022.09.081

2. Application of supramolecular solvent based on the surface-active ionic liquid in dispersive liquid–liquid microextraction of triazine herbicides in tea samples

Author:
Jilong Li; Fengze Wu; Yupu Zhang; Ji Feng; Xiujuan Wang; Yi Yang; Zhibing Wang; Hanqi Zhang
Source:
Food chemistry 2023 v.399 pp. 133901
ISSN:
0308-8146
Subject:
tetrahydrofuran,   etc   ; chemical species; dispersibility; food chemistry; ionic liquids; liquid-phase microextraction; microstructure; pH; tea; viscosity;     Show all 10 Subjects
Abstract:
... In this study, a novel supramolecular solvent based on surface-active ionic liquid was prepared and used as an extraction solvent for dispersive liquid–liquid microextraction of four triazine herbicides in tea samples. The formation mechanism, microstructure and physicochemical properties of supramolecular solvent were studied. Some parameters, including the molar ratio of surface-active ionic liq ...
DOI:
10.1016/j.foodchem.2022.133901

3. Novel amide- and imide-co-polymers modified with sulfathiazole as efficient chelator for selective extraction, pre-concentration and determination of trace inorganic antimony (as Sb(III)) from edible vegetable oils by ultrasound assisted-cloud point extraction coupled to micro-volume UV-spectrophotometry

Author:
H.B. Zengin; R. Gürkan
Source:
Journal of food composition and analysis 2023 v.115 pp. 104931
ISSN:
0889-1575
Subject:
tetrahydrofuran,   etc   ; absorbance; antimony; calibration; centrifugation; chelating agents; composite polymers; food composition; isopropyl alcohol; nonionic surfactants; pH; solvents; spectrophotometers; sulfathiazole; tautomerization; ultrasonics; vegetables;     Show all 17 Subjects
Abstract:
... The study described the synthesis, characterization, and application of newly prepared sulfathiazole-modified amide/imide co-polymers for the extraction of trace Sb(III) from edible vegetable oils. The method was based on the pH-dependent complexation between Sb(III) and chelators as a result of charge transfer via tautomerization in presence of the mixed ionic surfactants in 5%(v/v) 2-propanol, 1 ...
DOI:
10.1016/j.jfca.2022.104931

4. Ring Opening of Epoxides by Pendant Silanols

Author:
Someshwar Nagamalla; Joel T. Mague; Shyam Sathyamoorthi
Source:
Organic letters 2022 v.24 no.3 pp. 939-943
ISSN:
1523-7052
Subject:
tetrahydrofuran,   etc   ; arabitol; epoxides;     Show all 3 Subjects
Abstract:
... We present a new ring-opening reaction of epoxides by pendant silanols, catalyzed by either Ph₃C⁺BF₄– or BINOL-phosphoric acid. Silanol epoxides derived from trans-allylic alcohols, cis-allylic alcohols, trans-homoallylic alcohols, and cis-homoallylic alcohols were all compatible and gave products from either endo- or exo-ring opening. With silanol epoxides derived from 4-alkenyl silanols, an unus ...
DOI:
10.1021/acs.orglett.1c04310

5. The Tetrahydrofuran Motif in Polyketide Marine Drugs

Author:
Laura Fernández-Peña; Carlos Díez-Poza; Paula González-Andrés; Asunción Barbero
Source:
Marine drugs 2022 v.20 no.2 pp. -
ISSN:
1660-3397
Subject:
tetrahydrofuran,   etc   ; oxygen; polyketides;     Show all 3 Subjects
Abstract:
... Oxygen heterocycles are units that are abundant in a great number of marine natural products. Among them, marine polyketides containing tetrahydrofuran rings have attracted great attention within the scientific community due to their challenging structures and promising biological activities. An overview of the most important marine tetrahydrofuran polyketides, with a focused discussion on their i ...
DOI:
10.3390/md20020120

6. Highly Stereoselective Asymmetric Total Synthesis of (−)-Jimenezin via Sequential Intramolecular Amide Enolate Alkylation

Author:
Thien Nhan Lu; Minjung Kwak; Mallesham Samala; Minji Son; Jungjoong Hwang; Suresh Mandava; Thuy Trang Pham; Haeil Park; Hyoungsu Kim; Deukjoon Kim; Jongkook Lee
Source:
Organic letters 2022 v.24 no.8 pp. 1652-1656
ISSN:
1523-7052
Subject:
tetrahydrofuran,   etc   ; alkylation; oxygen; stereoselectivity;     Show all 4 Subjects
Abstract:
... A highly stereoselective asymmetric total synthesis of (−)-jimenezin (1), a potent anticancer acetogenin, was efficiently completed with the key feature being a sequential intramolecular amide enolate alkylation (IAEA). Our investigation to probe the origin of the complete stereoselectivity in the second IAEA step to form the conformationally flexible tetrahydrofuran with perfect stereocontrol ide ...
DOI:
10.1021/acs.orglett.2c00196

7. Straightforward Synthesis of Spirocyclic Tetrahydrofurans by a Reductive MCR/Iodoetherification Sequence

Author:
Marine Pinaud; Eric Huet; Marc Presset; Erwan Le Gall
Source:
Journal of organic chemistry 2022 v.87 no.7 pp. 4971-4980
ISSN:
1520-6904
Subject:
tetrahydrofuran,   etc   ; journals; ketones; organic chemistry;     Show all 4 Subjects
Abstract:
... A straightforward and modular sequence for the synthesis of substituted spirocyclic tetrahydrofurans is described. The strategy relies on a reductive cobalt-catalyzed three-component reaction between a cyclic ketone, an acrylate, and a vinylic bromide followed by an intramolecular iodoetherification of the resulting γ-hydroxyalkene. Some functional group interconversions allowed the preparation of ...
DOI:
10.1021/acs.joc.1c03034

8. Synthesis of Dithiocatechol-Pendant Polymers

Author:
Jincai Li; Joseph J. Richardson; Hirotaka Ejima
Source:
Journal of the American Chemical Society 2022 v.144 no.6 pp. 2450-2454
ISSN:
1520-5126
Subject:
tetrahydrofuran,   etc   ; crosslinking; oxidation; polymerization; spectroscopy;     Show all 5 Subjects
Abstract:
... Although the synthesis of thiophenol-pendant polymers was reported in the 1950s, the polymers generally suffered from oxidation and became insoluble in organic solvents, hampering detailed characterization and further applications. Dithiocatechol-pendant polymers, which have one additional ortho-thiol group than thiophenol-pendant polymers, have never been synthesized, despite their promise in var ...
DOI:
10.1021/jacs.1c11479

9. A rigidity–flexibility balance strategy enabling highly photoluminescent two-dimensional covalent organic framework nanosheets

Author:
Hao Wang; Chengtao Gong; Peng Jin; Chenglong Guo; Danfeng Wang; Guodong Xu; Yongwu Peng
Source:
Chemical communications 2022 v.58 no.70 pp. 9798-9801
ISSN:
1364-548X
Subject:
tetrahydrofuran,   etc   ; fluorescence; nanosheets; photoluminescence; tetracycline;     Show all 5 Subjects
Abstract:
... The fluorescence quenching phenomenon commonly found in two-dimensional COFs is due to either the strong interlayer π–π stacking or the non-radiative decay caused by intramolecular rotation. Here, we report a rigidity–flexibility balance strategy for constructing highly photoluminescent 2D COF nanosheets via the integration of rigid fluorescent molecular nodes with flexible non-planar building blo ...
DOI:
10.1039/d2cc03498k

10. Catalytic Asymmetric Umpolung Tandem Reactions of Hemiacetals via Dinuclear Zinc Cooperative Catalysis

Author:
Sheng-Nan Xing; Yuan-Zhao Hua; Xiao-Chao Yang; Si-Si Du; Shi-Kun Jia; Guang-Jian Mei; Min-Can Wang
Source:
Organic letters 2022 v.24 no.22 pp. 3909-3914
ISSN:
1523-7052
Subject:
tetrahydrofuran,   etc   ; Lewis bases; catalytic activity; quinoline; zinc;     Show all 5 Subjects
Abstract:
... The umpolung activity of hemiacetals serving as α-carbon nucleophiles has been reported via dinuclear zinc cooperative catalysis. This umpolung strategy has been applied to catalytic asymmetric tandem reactions of 1-tosylindoline-2,3-diols with β,γ-unsaturated-α-keto compounds, providing a broad series of structurally diverse tetrahydrofuran spirooxindoles and dihydrofurans, respectively. In addit ...
DOI:
10.1021/acs.orglett.2c00913

11. Nanobowls from Amphiphilic Core–Shell Cyclic Bottlebrush Polymers

Author:
Digvijayee Pal; John B. Garrison; Zhihui Miao; Lily E. Diodati; Adam S. Veige; Brent S. Sumerlin
Source:
Macromolecules 2022 v.55 no.17 pp. 7446-7453
ISSN:
1520-5835
Subject:
tetrahydrofuran,   etc   ; hydrophilicity; hydrophobicity; polymerization; polystyrenes; solvents; viscosity;     Show all 7 Subjects
Abstract:
... Cyclic bottlebrush polymers are macrocycles that contain pendent side-chain polymers on nearly every repeat unit. We leveraged a method to generate cyclic bottlebrush polymers utilizing ring-expansion polymerization (REP) followed by subsequent grafting-from via atom-transfer radical polymerization (ATRP) to produce core–shell cyclic bottlebrush polymers and investigated their self-assembly behavi ...
DOI:
10.1021/acs.macromol.2c01232

12. Ortho C–H Hydroxyalkylation or Methylation of Aryl Iodides by Ethers and TMSI via a Catellani Strategy

Author:
Zhe Zhang; Xi Chen; Xue-Song Li; Cui-Tian Wang; Zhi-Jie Niu; Bo-Sheng Zhang; Xue-Yuan Liu; Yong-Min Liang
Source:
Organic letters 2022 v.24 no.38 pp. 6897-6902
ISSN:
1523-7052
Subject:
tetrahydrofuran,   etc   ; catalytic activity; hydrogenation; iodides; methylation; palladium;     Show all 6 Subjects
Abstract:
... In this paper, in the presence of trimethylsilyl iodide, the direct ortho-C–H hydroxyalkylation/methylation of aryl iodines was effectively realized via palladium/norbornene cooperative catalysis when low-cost tetrahydrofuran and 1,2-dimethoxyethane were used as alkyl sources. Heck, Suzuki, and Sonogashira coupling and hydrogenation were all compatible with the reaction as termination steps. In ad ...
DOI:
10.1021/acs.orglett.2c02425

13. Palladium-Catalyzed Carbonylative [5+1] Cycloaddition of N-Tosyl Vinylaziridines: Solvent-Controlled Divergent Synthesis of α,β- and β,γ-Unsaturated δ-Lactams

Author:
Tao Zhang; Shichong Wang; Dandan Zuo; Jingjing Zhao; Wen Luo; Chaojie Wang; Pan Li
Source:
Journal of organic chemistry 2022 v.87 no.15 pp. 10408-10415
ISSN:
1520-6904
Subject:
tetrahydrofuran,   etc   ; cycloaddition reactions; dimethylformamide; organic chemistry; regioselectivity;     Show all 5 Subjects
Abstract:
... A palladium-catalyzed carbonylative [5+1] cycloaddition of N-tosyl vinylaziridines with CO has been developed. This protocol affords an efficient and practical approach for solvent-controlled divergent synthesis of α,β-unsaturated δ-lactams in dimethylformamide and β,γ-unsaturated δ-lactams in tetrahydrofuran in good to excellent yields. Significantly, the step- and atom-economical reactions are m ...
DOI:
10.1021/acs.joc.2c00710

14. Palladium-Catalyzed Para-C–H Bond Amination of 2-Aryl Chloromethylbenzenes

Author:
Yingqi Wang; Sheng Zhang; Xiujuan Feng; Xiaoqiang Yu; Masahiko Yamaguchi; Ming Bao
Source:
Journal of organic chemistry 2022 v.87 no.15 pp. 10531-10538
ISSN:
1520-6904
Subject:
tetrahydrofuran,   etc   ; amination; benzene; organic chemistry; phosphine; regioselectivity;     Show all 6 Subjects
Abstract:
... Palladium-catalyzed para-C–H bond amination of 2-aryl chloromethylbenzenes is described for the first time. The reactions of 2-aryl chloromethylbenzenes with cyclic amines proceeded smoothly in the presence of Pd(acac)₂, tri(2-furyl)phosphine, and NaH in tetrahydrofuran at 40 °C to provide para-C–H bond aminated products in satisfactory to high yields with acceptable regioselectivity in most cases ...
DOI:
10.1021/acs.joc.2c01233

15. Rate coefficient and mechanism of the OH-initiated degradation of cyclobutanol: A combined experimental and theoretical study

Author:
María de los A. Garavagno; Federico J. Hernández; Rafael A. Jara-Toro; Genesys Mahecha; Javier A. Barrera; Raúl A. Taccone; Gustavo A. Pino
Source:
Atmospheric environment 2022 v.268 pp. 118821
ISSN:
1352-2310
Subject:
tetrahydrofuran,   etc   ; air; environment; hydroxyl radicals; reaction mechanisms;     Show all 5 Subjects
Abstract:
... The degradation process of cyclobutanol (cButOH) by hydroxyl radical (OH), under atmospheric conditions, (750 ± 10) Torr of air and (296 ± 2) K, has been studied. The rate coefficient for the title reaction (k₂₉₆K = (7.3 ± 0.6) x 10⁻¹² cm³ molecule⁻¹ s⁻¹) was determined at 296 K by the conventional relative-rate method. Electronic structure calculations with uCCSD(T)/uBHandHLYP/aug-cc-PVDZ were co ...
DOI:
10.1016/j.atmosenv.2021.118821

16. Activation of the CP bond in phosphanylphosphaalkenes (CP–P bond system) in the reaction with nucleophilic reagents: MeLi, nBuLi and tBuLi

Author:
Aleksandra Ziółkowska; Natalia Szynkiewicz; Łukasz Ponikiewski
Source:
RSC advances 2022 v.12 no.18 pp. 10989-10996
ISSN:
2046-2069
Subject:
tetrahydrofuran,   etc   ; Lewis bases; ambient temperature; biphenyl; phosphorus;     Show all 5 Subjects
Abstract:
... Three reactions of phosphanylphosphaalkene (1) with nucleophiles were performed to activate the diphosphorus monomer. We observed similar results in the reactions with MeLi and nBuLi, in which the P–P bond is cleavaged and triphosphorus systems [P(Me)₂–CH(biph)–CH(biph)–P–(PtBu₂)]⁻ (1a′′) and [P(nBu)₂–CH(biph)–CH(biph)–P–(PtBu₂)]⁻ (1b′′), respectively, are formed depending on the nucleophilic reag ...
DOI:
10.1039/d1ra09215d

17. Etherification via Aromatic Substitution on 1,3-Disubstituted Benzene Derivatives

Author:
Marina Tsuzaki; Shin Ando; Tadao Ishizuka
Source:
Journal of organic chemistry 2022 v.87 no.2 pp. 1357-1365
ISSN:
1520-6904
Subject:
tetrahydrofuran,   etc   ; Lewis bases; alcohols; benzene; chlorides; dimethylformamide; organic chemistry;     Show all 7 Subjects
Abstract:
... In this study, we developed a method for etherification via aromatic substitution at the ipso-position of an electron-withdrawing group (EWG) that exists at the meta-position of another EWG. To heighten the reactivity of the substitution reaction, we added a t-BuOK solution in tetrahydrofuran (THF) to a mixture of an aromatic substrate, an alcoholic nucleophile, and 18-crown-6-ether in dimethylfor ...
DOI:
10.1021/acs.joc.1c02670

18. Catalytic conversion of cellulose to levoglucosenone using propylsulfonic acid functionalized SBA-15 and H2SO4 in tetrahydrofuran

Author:
Oscar Oyola-Rivera; Jiayue He; George W. Huber; James A. Dumesic; Nelson Cardona-Martínez
Source:
Biomass and bioenergy 2022 v.156 pp. 106315
ISSN:
0961-9534
Subject:
tetrahydrofuran,   etc   ; bioenergy; biomass; catalysts; cellulose; depolymerization; liquids; sulfuric acid;     Show all 8 Subjects
Abstract:
... The catalytic conversion of cellulose to levoglucosenone (LGO) was studied using dilute sulfuric acid and propylsulfonic acid functionalized SBA-15 (PS-SBA-15) in tetrahydrofuran (THF). We show that the addition of small amounts of a liquid acid catalyst such as sulfuric acid complements the use of a solid acid catalyst for the conversion of cellulose. Sulfuric acid promotes the depolymerization o ...
DOI:
10.1016/j.biombioe.2021.106315

19. Convergent Synthesis of the C1–C29 Framework of Amphidinolide F

Author:
Filippo Romiti; Ludovic Decultot; J. Stephen Clark
Source:
Journal of organic chemistry 2022 v.87 no.12 pp. 8126-8141
ISSN:
1520-6904
Subject:
tetrahydrofuran,   etc   ; Lewis bases; aldehydes; boron; carbon; diastereoselectivity; organic chemistry; rhodium;     Show all 8 Subjects
Abstract:
... The complete carbon framework of the macrocyclic marine natural product amphidinolide F has been prepared by a convergent synthetic route in which three fragments of similar size and complexity have been coupled. Key features of the syntheses of the fragments include the stereoselective construction of the tetrahydrofuran in the C1–C9 fragment by oxonium ylide (free or metal-bound) formation and r ...
DOI:
10.1021/acs.joc.2c00850

20. Utilizing a needle as a source of iron in synergistic dual photoredox catalytic generation of alkoxy radicals

Author:
Alica Ondrejková; Rickard Lindroth; Göran Hilmersson; Carl-Johan Wallentin
Source:
Chemical communications 2022 v.58 no.73 pp. 10241-10244
ISSN:
1364-548X
Subject:
tetrahydrofuran,   etc   ; alcohols; catalytic activity; chemoselectivity; corrosion; iron; light; redox reactions;     Show all 8 Subjects
Abstract:
... A visible-light mediated alkoxy radical generation is described, which allows for a structurally divergent oxidative C(sp³)–H bond functionalization. This protocol employs a photoredox/iron dual catalysis allowing for an unprecedented chemoselective single-step transformation of alcohol derivatives giving access to two valuable sets of products, tetrahydrofurans and γ-bromoketones, under one set o ...
DOI:
10.1039/d2cc03262g