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201.
The effectiveness of chiral phosphine oxide BINAPO as a catalyst for the enantioselective addition of allyltrichlorosilanes to aldehydes was demonstrated, wherein the combination of diisopropylethylamine and tetrabutylammonium iodide as additives is crucial for accelerating the catalytic cycle. 相似文献
202.
Preparation and Polymerization of 2-(Phthalimido)ethyl 10′-(Methacryloyloxy)decyl Hydrogen Phosphate
The preparation and polymerization of 2-(phthalimido)ethyl 10′-(methacryloyloxy)decyl hydrogen phosphate are described. This monomer was polymerized with 2, 2′-azobisisobutyro-nitrile (AIBN). The properties of the resultant polymer are also described. 相似文献
203.
Some 2-(β-substituted acryloyl)-l-methacryloyloxy-naphthalenes (II) were synthesized by the reaction of the corresponding 2-(β-substituted acryloyl)-l-naphthols with methacryloyl chloride. These monomers were polymerized with 2, 2′-azoisobutyronitrile. The properties of the resulting oligomers as photosensitive resins are described. 相似文献
204.
Abstract New phospholipid analogous polymers were prepared by radical copolymerizations of 2-(methacryloyloxy)ethyl-2-(trimethylammonio)-ethyl phosphate and poly(ethylene glycol)monomethylether methacrylates (PEGMM) at room temperature, using (NH4)2S2O8 as the initiator and pure water as the solvent. The copolymers obtained were characterized based on their IR, 1H-, and 13C-NMR spectral data and melting point measurements. The molecular weights of these copolymers decrease as the length of the PEGMM side chain increases. These new polymers, which contain phosphatidylcholine analogous groups in their side chains, show viscosity properties similar to typical polyelectrolytes. 相似文献
205.
Abstract A series of amphiphilic phospholipid analogous acrylamide monomers and homopolymers containing long alkyl chains as the hydrophobic groups and phosphatidylcholine analogues as the hydrophilic groups were used to study the properties of monolayers and multilayers. The P-A isotherms of the monolayers for these monomers and polymers were measured at different temperatures. The temperature and length dependence of alkyl chains, and the difference between monomers and polymers were investigated, respectively. On the other hand, the LB multilayers of all monomers and polymers were prepared. The contact angles of LB films obtained with pure water were also measured. 相似文献
206.
During the investigation on the mechanism of the rearrangement reaction of the dihydroindenone derivatives (1 and 2)1), we need to prepare β-methyl derivative such as 1m. 相似文献
207.
Hiroyuki Sasada Yasuo Hasegawa Takayoshi Amano Tadao Shimizu 《Journal of Molecular Spectroscopy》1982,96(1):106-130
More than two thousand Stark resonances of the ν4 and 2ν2 band transitions of 14NH3 and 15NH3 were observed at Doppler-limited resolution with a CO laser. Fourier transform infrared spectroscopy on 15NH3 is also carried out. Thirty-six new microwave transitions including seven perturbation-enhanced transitions are observed in the v4 = 1 excited vibrational state of 14NH3 and 15NH3. Accuracies of all available spectroscopic data on the v4 = 1 and the v2 = 2 states are evaluated and analyses of the vibration-rotation spectra are performed. The Coriolis interaction between the closely lying v4 = 1 a (antisymmetric level) and v2 = 2 s (symmetric level) states is explicitly included in the analysis. Smaller Coriolis interactions between the v4 = 1 a and the v2 = 1 s states and between the v2 = 2 s and the v2 = v4 = 1 a states (i.e., (v1, v2, v′3, v′4) = (0 1 00 11)) are also taken into consideration. The accuracy in determination of the principal molecular constants is 10?6. The parameters thus obtained reproduce the frequencies of the vibration-rotation transitions and inversion transitions within the accuracy of 0.0024 cm?1. 相似文献
208.
209.
Synthesis of amphiphilic block copolymer consisting of glycopolymer and poly(l‐lactide) and preparation of sugar‐coated polymer aggregates
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Makoto Obata Ryota Otobuchi Tadao Kuroyanagi Masaki Takahashi Shiho Hirohara 《Journal of polymer science. Part A, Polymer chemistry》2017,55(3):395-403
The block glycopolymer, poly(2‐(α‐d ‐mannopyranosyloxy)ethyl methacrylate)‐b‐poly(l ‐lactide) (PManEMA‐b‐PLLA), was synthesized via a coupling approach. PLLA having an ethynyl group was successfully synthesized via ring‐opening polymerization using 2‐propyn‐1‐ol as an initiator. The ethynyl functionality of the resulting polymer was confirmed by MALDI‐TOF mass spectroscopy. In contrast, PManEMA having an azide group was prepared via AGET ATRP using 2‐azidopropyl 2‐bromo‐2‐methylpropanoate as an initiator. The azide functionality of the resulting polymer was confirmed by IR spectroscopy. The Cu(I)‐catalyzed 1,3‐dipolar cycloaddition between PLLA and PManEMA was performed to afford PManEMA‐b‐PLLA. The block structure was confirmed by 1H NMR spectroscopy and size exclusion chromatography. The aggregating properties of the block glycopolymer, PManEMA16k‐b‐PLLA6.4k (M n,PManEMA = 16,000, M n,PLLA = 6400) was examined by 1H NMR spectroscopy, fluorometry using pyrene, and dynamic light scattering. The block glycopolymer formed complicated aggregates at concentrations above 21 mg·L?1 in water. The d ‐mannose presenting property of the aggregates was also characterized by turbidimetric assay using concanavalin A. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 395–403 相似文献
210.
A sequential injection (SI) method in a lab-on-valve (LOV) format for simultaneous spectrophotometric determination of copper and iron has been devised. The detection chemistry is based on the complex formation of 2-(5-bromo-2-pyridylazo)-5-[N-n-propyl-N-(3-sulfopropyl)amino]aniline (5-Br-PSAA) with copper(II) and/or iron(II) at pH 4.6. Copper(II) reacts with 5-Br-PSAA to form the complex which has an absorption maximum at 580 nm but iron(III) does not react. In the presence of a reducing agent only iron(II)-5-Br-PSAA complex is formed and detected at 558 nm. Under the optimum experimental conditions, the determinable ranges are 0.1-2 mg l−1 for copper and 0.1-5 mg l−1 for iron, respectively, with a sampling rate of 18 h−1. The limits of detection are 50 μg l−1 for copper and 25 μg l−1 for iron. The relative standard deviations (n = 15) are 2% for 0.5 mg l−1 copper and 1.8% for 0.5 mg l−1 iron when determined in standard solutions. The recoveries range between 96 and 105% when determining 0.25-2 mg l−1 of copper and 0.2-5 mg l−1 of iron in artificial mixtures at copper/iron ratios of 1:10 to 5:1. The proposed SI-LOV method is successfully applied to the simultaneous determination of copper and iron in multi-element standard solution and in industrial wastewater samples. 相似文献