116404-47-8Relevant articles and documents
Design, Synthesis, and Self-Assembly of Polymers with Tailored Graft Distributions
Chang, Alice B.,Lin, Tzu-Pin,Thompson, Niklas B.,Luo, Shao-Xiong,Liberman-Martin, Allegra L.,Chen, Hsiang-Yun,Lee, Byeongdu,Grubbs, Robert H.
, p. 17683 - 17693 (2017)
Grafting density and graft distribution impact the chain dimensions and physical properties of polymers. However, achieving precise control over these structural parameters presents long-standing synthetic challenges. In this report, we introduce a versatile strategy to synthesize polymers with tailored architectures via grafting-through ring-opening metathesis polymerization (ROMP). One-pot copolymerization of an ω-norbornenyl macromonomer and a discrete norbornenyl comonomer (diluent) provides opportunities to control the backbone sequence and therefore the side chain distribution. Toward sequence control, the homopolymerization kinetics of 23 diluents were studied, representing diverse variations in the stereochemistry, anchor groups, and substituents. These modifications tuned the homopolymerization rate constants over 2 orders of magnitude (0.36 M-1 s-1 homo -1 s-1). Rate trends were identified and elucidated by complementary mechanistic and density functional theory (DFT) studies. Building on this foundation, complex architectures were achieved through copolymerizations of selected diluents with a poly(d,l-lactide) (PLA), polydimethylsiloxane (PDMS), or polystyrene (PS) macromonomer. The cross-propagation rate constants were obtained by nonlinear least-squares fitting of the instantaneous comonomer concentrations according to the Mayo-Lewis terminal model. In-depth kinetic analyses indicate a wide range of accessible macromonomer/diluent reactivity ratios (0.08 1/r2 20), corresponding to blocky, gradient, or random backbone sequences. We further demonstrated the versatility of this copolymerization approach by synthesizing AB graft diblock polymers with tapered, uniform, and inverse-tapered molecular "shapes." Small-angle X-ray scattering analysis of the self-assembled structures illustrates effects of the graft distribution on the domain spacing and backbone conformation. Collectively, the insights provided herein into the ROMP mechanism, monomer design, and homo- and copolymerization rate trends offer a general strategy for the design and synthesis of graft polymers with arbitrary architectures. Controlled copolymerization therefore expands the parameter space for molecular and materials design.
Serendipitous and acid catalyzed synthesis of spirolactones
Kotha, Sambasivarao,Dipak, Mirtunjay Kumar,Mobin, Shaikh M.
, p. 4616 - 4619 (2011)
Formation of three diasteroisomeric spirodilactones 14a-c and 11 has been reported from diester 13 and 9, respectively, under the influence of mineral acid.
Diels-Alder reactions in chloroaluminate ionic liquids: Acceleration and selectivity enhancement
Lee, Carlos W.
, p. 2461 - 2464 (1999)
The utility of room temperature chloroaluminate ionic liquids as solvent and catalyst for the synthetically important Diels-Alder reaction was studied. The AlCl3-1-ethyl-3-methyl-1H-imidazolium chloride medium proved to be ideally suited for Diels-Alder reactions. Endo selectivity and rate enhancement were observed for the cyclopentadiene/methyl acrylate Diels- Alder reaction.
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Inukai,Kojima
, p. 2032 (1966)
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The mechanism of on-water catalysis
Beattie, James K.,McErlean, Christopher S. P.,Phippen, Christopher B. W.
, p. 8972 - 8974 (2010)
Acid catalysis by interfacial water: A new mechanism is proposed for onwater catalysis, the acceleration of organic reactions when conducted in aqueous emulsions. It involves the protonation of a substrate by water, driven by the strong adsorption of hydroxide ions at aqueous interfaces with oils. This accounts for the specific role of water, and a deuterium isotope effect, at the interface, on reactions known to be acid-catalysed.
Diels-Alder reaction in protic ionic liquids
Janus, Ewa,Goc-Maciejewska, Izabela,?ozyński, Marek,Pernak, Juliusz
, p. 4079 - 4083 (2006)
Protic imidazolium ionic liquids have been tested as reaction media in the Diels-Alder reaction between cyclopentadiene and two dienophiles (dimethyl maleate and methyl acrylate). Good conversions and endo/exo selectivities were achieved. The activation of the dienophile by hydrogen bonding with protic imidazolium ILs was demonstrated.
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Koch,H.
, p. 292 - 302 (1962)
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Norbornane-based cationic antimicrobial peptidomimetics targeting the bacterial membrane
Hickey, Shane M.,Ashton, Trent D.,Boer, Gareth,Bader, Christie A.,Thomas, Michael,Elliott, Alysha G.,Schmuck, Carsten,Yu, Heidi Y.,Li, Jian,Nation, Roger L.,Cooper, Matthew A.,Plush, Sally E.,Brooks, Douglas A.,Pfeffer, Frederick M.
, p. 9 - 22 (2018)
The design, synthesis and evaluation of a small series of potent amphiphilic norbornane antibacterial agents has been performed (compound 10 MIC = 0.25 μg/mL against MRSA). Molecular modelling indicates rapid aggregation of this class of antibacterial agent prior to membrane association and insertion. Two fluorescent analogues (compound 29 with 4-amino-naphthalimide and 34 with 4-nitrobenz-2-oxa-1,3-diazole fluorophores) with good activity (MIC = 0.5 μg/mL against MRSA) were also constructed and confocal microscopy studies indicate that the primary site of interaction for this family of compounds is the bacterial membrane.
TETRACARBOXYLIC DIANHYDRIDE, CARBONYL COMPOUND, POLYIMIDE PRECURSOR RESIN, AND POLYIMIDE
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Paragraph 0077-0078, (2021/04/30)
A tetracarboxylic dianhydride which is a compound represented by the following general formula (1): [in the formula (1), A represents one selected from the group consisting of optionally substituted divalent aromatic groups in each of which the number of carbon atoms forming an aromatic ring is 6 to 30, and Ras each independently represent a hydrogen atom or the like], wherein 60% by mass or more of a stereoisomer contained in the compound is an exo/exo type stereoisomer represented by a specific general formula.
