1791-26-0Relevant articles and documents
Living Anionic Polymerization of N-(1-Adamantyl)-N-4-vinylbenzylideneamine and N-(2-Adamantyl)-N-4-vinylbenzylideneamine: Effects of Adamantyl Groups on Polymerization Behaviors and Thermal Properties
Kang, Beom-Goo,Shoji, Hideo,Kataoka, Hiroshi,Kurashima, Reo,Lee, Jae-Suk,Ishizone, Takashi
, p. 8489 - 8496 (2015)
The anionic polymerization of N-(1-adamantyl)-N-4-vinylbenzylideneamine (1) and N-(2-adamantyl)-N-4-vinylbenzylideneamine (2) was performed using various initiators, such as oligo(α-methylstyryl)dipotassium, potassium naphthalenide, diphenylmethylpotassium, and diphenylmethyllithium, in THF at -78°C for 1 h to investigate the effects of adamantyl groups on the polymerization behaviors and thermal properties of the resulting polymers. The well-defined poly(1) and poly(2) with predictable molecular weights and narrow molecular weight distributions were successfully obtained, indicating that the bulky adamantyl groups effectively protected the carbon-nitrogen double bond (Ci=N) from the nucleophilic attack of the initiators and the propagating chain ends. The stability of the propagating chain end of poly(1) was confirmed by the quantitative efficiencies in the postpolymerization and the sequential copolymerization with tert-butyl methacrylate. A poly(4-formylstyrene) was quantitatively formed by the acidic hydrolysis reaction of the N-adamantylimino groups of the poly(1). The resulting poly(1) and poly(2) showed significantly high glass transition temperatures (Tg) at 257 and 209°C, respectively, due to the bulky and stiff adamantyl substituents. It was also found that the substituted position of adamantane unit and the linkage between polystyrene backbone and adamantyl groups played very important roles to determine the Tg values of the substituted polystyrenes.
Antibiotic protected silver nanoparticles for microbicidal cotton
Montagut, Ana Maria,Granados, Albert,Ballesteros, Anna,Pleixats, Roser,Llagostera, Montserrat,Cortés, Pilar,Sebastián, Rosa María,Vallribera, Adelina
, p. 102 - 108 (2019)
Surface coating of metal nanoparticles is one of the major aspects to be optimized in the design of antimicrobial nanoparticles. The novelty of this work is that antimicrobial derivatives have been used as stabilizers to protect silver nanoparticles (Ag NPs). Microbicidal activity studies of fabricated cotton textiles coated with these Ag@Antibio were performed. Protective ligand layers of Ag NPs resulted to be a deterministic factor in their antimicrobial activity. The best bactericidal activity was obtained for Fabric TAM (coated with Ag NPs with triarylmethane derivates in surface, Ag@TAMSH), with a bacterial decrease of 3 log units for the S. aureus strain. Intrinsic antibiotic activity and partial positive charge of the TAMSH probably enhanced their antimicrobial effects. Fabric Eu (coated with Ag NPs with eugenol derivates in surface, Ag@EugenolSH) and Fabric FQPEG (coated with Ag NPs embedded in PEG-fluoroquinolone derivatives in surface, Ag@FQPEG) displayed antibacterial activity for both Staphylococcus aureus and Pseudomonas aeruginosa strains. These coated antimicrobial cotton fabrics can be applied in different medical textiles.
Preparation method of cyclic carbonate
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Paragraph 0029; 0034-0035, (2021/11/03)
The invention belongs to the technical field of materials, and particularly relates to a preparation method of a cyclic carbonate, which takes a double-center porous polymer as a catalyst and catalysis CO. 2 The conversion is cyclic carbonate, and the double-center porous polymer is a double-center heterogeneous porous catalyst of metalloporphyrin and quaternary phosphonium sites. The invention solves the problem of complicated recovery of the catalyst for synthesis of the existing cyclocarbonate, utilizes the double-center porous polymer containing the metalloporphyrin and the quaternary phosphonium site as a catalyst to realize the combination and synergistic combination of the two active centers on the molecular level, thereby efficiently converting carbon dioxide into cyclic carbonate.
Double-center porous polymer and preparation method thereof
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Paragraph 0025; 0032-0033, (2021/11/21)
The invention belongs to the technical field of catalysts, and particularly relates to a double-center porous polymer, a preparation method thereof, a porphyrin and 4 - (diphenylphosphino) styrene monomer which are functionalized by vinyl, and are prepared by quaternary phosphonium and metal coordination. The invention solves the defect that an existing porous catalyst structure is not easy to regulate and control, utilizes metalloporphyrin and quaternary phosphonium sites as an active center and is fixed in a porous polymer to form a double-center heterogeneous porous catalyst.
Vinyl Thianthrenium Tetrafluoroborate: A Practical and Versatile Vinylating Reagent Made from Ethylene
Juliá, Fabio,Paulus, Fritz,Ritter, Tobias,Yan, Jiyao
supporting information, p. 12992 - 12998 (2021/09/03)
The use of vinyl electrophiles in synthesis has been hampered by the lack of access to a suitable reagent that is practical and of appropriate reactivity. In this work we introduce a vinyl thianthrenium salt as an effective vinylating reagent. The bench-stable, crystalline reagent can be readily prepared from ethylene gas at atmospheric pressure in one step and is broadly useful in the annulation chemistry of (hetero)cycles, N-vinylation of heterocyclic compounds, and palladium-catalyzed cross-coupling reactions. The structural features of the thianthrene core enable a distinct synthesis and reactivity profile, unprecedented for other vinyl sulfonium derivatives.
Oxoammonium Salt-Mediated Regioselective Vicinal Dioxidation of Alkenes: Relying on Transient and Persistent Nitroxides
Chen, Fei,Ge, Ming-Jing,Liu, Shi-Yu,Wu, Lu-Yan,Yang, Hao,Yang, Qing-Yun,Zheng, Yang,Zhu, Xin-Yue
supporting information, p. 8533 - 8538 (2021/11/17)
A novel, easy-to-handle, and regioselective vicinal dioxidation of alkenes under transition metal and organic peroxide free conditions has been developed. This approach uses N-hydroxyphthalimide and its analogues as the transient nitroxyl-radical precursors and 2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (TEMPO+BF4-) as the oxidant as well as the source of persistent nitroxide. By employing this method, multifarious structurally important dioxidation products were efficiently synthesized from simple alkenes and complex bioactive molecule derivatives.
Nickel-Catalyzed Reductive Cross-Coupling of Aryl Bromides with Vinyl Acetate in Dimethyl Isosorbide as a Sustainable Solvent
Huang, Xia,Jin, Jian,Lei, Chuanhu,Su, Mincong
supporting information, (2022/01/15)
A nickel-catalyzed reductive cross-coupling has been achieved using (hetero)aryl bromides and vinyl acetate as the coupling partners. This mild, applicable method provides a reliable access to a variety of vinyl arenes, heteroarenes, and benzoheterocycles, which should expand the chemical space of precursors to fine chemicals and polymers. Importantly, a sustainable solvent, dimethyl isosorbide, is used, making this protocol more attractive from the point of view of green chemistry.
DIBALH: From known fundamental to an unusual reaction; Chemoselective partial reduction of tertiary amides in the presence of esters
An, Duk Keun,Heo, Yu Jin,Jaladi, Ashok Kumar,Kim, Hyun Tae
, p. 33809 - 33813 (2021/12/09)
This study presents a quick and reliable approach to the chemoselective partial reduction of tertiary amides to aldehydes in the presence of readily reducible ester groups using commercial DIBALH reagent. Moreover, the developed method was also extended to multi-functional molecules bearing ester moieties, which were successfully chemoselectively reduced to the corresponding aldehydes. This journal is
The Stereoselective Oxidation of para-Substituted Benzenes by a Cytochrome P450 Biocatalyst
Chao, Rebecca R.,Lau, Ian C.-K.,Coleman, Tom,Churchman, Luke R.,Child, Stella A.,Lee, Joel H. Z.,Bruning, John B.,De Voss, James J.,Bell, Stephen G.
supporting information, p. 14765 - 14777 (2021/09/14)
The serine 244 to aspartate (S244D) variant of the cytochrome P450 enzyme CYP199A4 was used to expand its substrate range beyond benzoic acids. Substrates, in which the carboxylate group of the benzoic acid moiety is replaced were oxidised with high activity by the S244D mutant (product formation rates >60 nmol.(nmol-CYP)?1.min?1) and with total turnover numbers of up to 20,000. Ethyl α-hydroxylation was more rapid than methyl oxidation, styrene epoxidation and S-oxidation. The S244D mutant catalysed the ethyl hydroxylation, epoxidation and sulfoxidation reactions with an excess of one stereoisomer (in some instances up to >98 %). The crystal structure of 4-methoxybenzoic acid-bound CYP199A4 S244D showed that the active site architecture and the substrate orientation were similar to that of the WT enzyme. Overall, this work demonstrates that CYP199A4 can catalyse the stereoselective hydroxylation, epoxidation or sulfoxidation of substituted benzene substrates under mild conditions resulting in more sustainable transformations using this heme monooxygenase enzyme.
Nickel-Catalyzed Ligand-Free Hiyama Coupling of Aryl Bromides and Vinyltrimethoxysilane
Wei, Shichao,Mao, Yongjun,Shi, Shi-Liang
supporting information, p. 1670 - 1674 (2021/02/26)
We herein disclose the first Ni-catalyzed Hiyama coupling of aryl halides with vinylsilanes. This protocol uses cheap, nontoxic, and stable vinyltrimethoxysilane as the vinyl donor, proceeds under mild and ligand-free conditions, furnishing a diverse variety of styrene derivatives in high yields with excellent functional group compatibility.
