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Monomers That Expand During Polymerization
Published in Rajender K. Sadhir, Russell M. Luck, Expanding Monomers, 2020
Russell M. Luck, Rajender K. Sadhir
Preparation of DBSOC (25) — A mixture of 23 (25 g, 0.75 mol), 24 (14.5 g, 0.38 mol), and anhydrous p-toluenesulfonic acid (0.15 g, 0.87 mol) in dry xylene (40 ml) was heated at 110°C for 10 h. During the reaction, ethanol was distilled off. The collection of the theoretical amount of ethanol was followed by the addition of triethylamine (1 ml) after cooling. The mixture was allowed to stand overnight at room temperature. Thereafter, removal of xylene under vacuum afforded a white precipitate which was recrystallized. Yield: 83%; mp 100 to 102°C. The NMR spectrum had bands at 8 values 2.00 to 2.3 (2H, m, 2 CH), 2.35 to 272 (4H, d, 2 PhCH2), 3.6 to 4.24 (8H, m, 4 CH20), 7.10 to 7.40 (10H, s, 2 Ph). Elemental analysis of 25 was in good agreement with the theoretical values. Calculated for C21H24O4:C, 74.09; H,7.11. Found: C, 73,82; H, 7.25. ()
Elimination Reactions
Published in Michael B. Smith, A Q&A Approach to Organic Chemistry, 2020
In the aqueous solvent the ammonium cation and the hydroxide anion are solvent-separated, so an intramolecular reaction is not possible. However, the triethylamine unit is a good leaving group and hydroxide is a base, so an E2 intermolecular reaction of the ammonium salt leads to but-2-ene and triethylamine as products, along with water. If the trimethylammonium salt is used rather than the triethylammonium salt, an E2 reaction will be preferred under these conditions and the products will be but-2-rne and trimethylamine. What is Cope elimination?
Synthesis and thermo-responsive properties of poly(N-vinyl caprolactam)/polyether segmented networks
Published in Y. Yagci, M.K. Mishra, O. Nuyken, K. Ito, G. Wnek, Tailored Polymers & Applications, 2020
Natalya A. Yanul, Yury E. Kirsh, Sam Verbrugghe, Eric J. Goethals, Filip E. Du Prez
The synthesis of α,ω-acrylate terminated PEO (illustrated for Mn = 2000) starts from the commercially available PEG. Into a 500 ml three-necked flask, equipped with a magnetic stirrer, 0.05 mol dried PEG (100 g), 200 ml of dichloromethane and 0.11 mol of triethylamine (proton trap) were charged under nitrogen atmosphere. To this mixture, 0.11 mol of methacryloyl chloride was added dropwise at a temperature below 10°C. The esterification reaction proceeded overnight at room temperature. The solution was filtrated several times to remove the precipitated triethylamine hydrochloride salt. The clear liquid was washed with 5% NaOH and several times with distilled water until it became neutral. After treatment with MgSO4 to remove water, the solution was filtered and CH2Cl2 was removed by rotary evaporation. Further drying was done under high vacuum at room temperature. A yield of approximately 85% was obtained.
Crystalline bis(η5-cyclopentadienyl)bis(benzoato/carboxylato)titanium(IV) precursor-directed route to functional titanium dioxide nanomaterials
Published in Journal of Coordination Chemistry, 2018
Tushar S. Basu Baul, Rajesh Manne, Edward R. T. Tiekink
Bis(η5-cyclopentadienyl)titanium(IV) dichloride, pivalic acid, t-butyl acetic acid, p-toluic acid (Merck), 2-furoic acid, and 3-furoic acid (SRL) were used without purification. The solvents used in the reactions were of AR grade and dried using standard procedures. Benzene, toluene, hexane, and THF were distilled from benzophenone/sodium while methanol was distilled over activated magnesium. Triethylamine was dried over calcium hydride and distilled. All manipulations were performed using standard Schlenk anaerobic lines in an atmosphere of dry dinitrogen or argon, unless otherwise stated.
Synthesis and chemical properties of Di(2-fluoro-2-polyfluoroalkyl- alkenyl)sulfides and 2,6-bis(polyfluoroalkyl)-1,4-oxathiine 4,4-dioxides
Published in Journal of Sulfur Chemistry, 2019
Yaroslav Borodkin, Eduard Rusanov, Anatolii Marchenko, Yuriy Koidan, Yuriy Shermolovich
To a stirred solution of triethylamine (0.35 g, 0.00346 mol) in 20 ml of anhydrous dioxane the solution of polyfluoroalkylsulfone (4a-c) (0.00173 mol) in 10 ml of anhydrous dioxane was added at room temperature. After the completion of the addition (15 min), chlorotrimethylsilane (0.38 g, 0.00346 mol) was added. The solution was stirred at room temperature for 48 h. The precipitate of triethylamine hydrochloride was filtered. Filtrate was evaporated under vacuum 10–20 mm Hg at 30–35°C and sulfones 5b,c were purified by crystallization from hexane.
pH-responsive nanomicelles of poly(ethylene glycol)-poly(ε-caprolactone)-poly(L-histidine) for targeted drug delivery
Published in Journal of Biomaterials Science, Polymer Edition, 2020
Penghui Wang, Wei Liu, Shuai Liu, Rong Yang, Yajie Pu, Wenjie Zhang, Xiaoxue Wang, Xin Liu, Yanhan Ren, Bo Chi
DOX·HCL (12 mg) was added in DMF (12 mL), and then added 0.1 mL TFA stirred at room temperature for 2 h. The solution was filtered to remove triethylamine hydrochloride. Later the filtrate was poured into flask, and then dissolved in DMF (10 ml) of PCG (60 mg, mDOX: mPEG-PCL-Phis = 1: 5) was added in the filtrate stirred for 12 h. The pure water was added slowly in the mixture stirred for 3 h. The mixture was poured into dialysis tubing (3.5 kDa MVCO) at DI water for 36 h to remove DMF and unloaded DOX. The product was dried by freeze drying.