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1.
The Structure of “;Trichloro-diphenoxyphosphorane” The structure of ‘Trichloro-diphenoxyphosphorane’ synthesized by well-known and new methods is not a pentacoordinated phosphorus compound, but has the structure of tetraphen-oxyphosphonium hexachlorophosphate 4 .  相似文献   

2.
Regio- and Stereospecific Addition of Diazomethane to Gibberellic Acid: A New Effective Pathway to 1α,2α-Methylenegibberellins A new pathway to 1α,2α-methylenegibberellines via pyrazoline intermediates is reported. In contrast to the addition of diazomethane to the Δ1-double bond of corresponding enones in the case of 1 “Umpolung” of the regioselectivity with cis-addition from the α-side to give pyrazoline ester 4 is observed. Subsequent photolysis of 4 leads to the 1,2-cyclopropyl derivative 6. The structures of the key compounds 4 and 6 are confirmed especially by n.m.r. and X-Ray analysis.  相似文献   

3.
Synthesis of „Ethyl-Brahmanol”︁ The synthesis of the title compound ( 11 ) from ethylapopinene ( 5 ) by oxydation to the epoxide ( 6 ), rearrangement to “ethyl-α-campholene aldehyde” ( 7 ) and its aldol condensation is described.  相似文献   

4.
孙桂春 《山东化工》2009,38(9):8-11
4-氯-2-氨基苯酚重氮化后,分别与1-(4’-磺酸基)苯基-3-甲基-5-吡唑酮和1-苯基-3-甲基-5-吡唑酮偶合,得到偶氮物I和偶氮物Ⅱ;偶氮物I和氧化铬铬化反应得到络合物Ⅲ;络合物Ⅲ再与偶氮物Ⅱ在碱性条件下反应得到红色不对称金属络合染料(酸性红S—GN)。本文介绍了该染料的化学结构及合成方法。  相似文献   

5.
6.
A lable‐free, simple, and sensitive fluorescence “turn‐on” approach is designed to rapidly detect protein using a conjugated polythiophene derivative (PDPMT‐Cl). The fluorescence of PDPMT‐Cl solution can be efficiently quenched by PtCl42? ions. Upon adding trypsin to the (bovine serum albumin, BSA) PDPMT‐Cl–PtCl42? solution, the BSA is cleaved into amino acid or peptide fragments, which are stronger PtCl42? ions chelators to form more stable complexes with PtCl42? ions. Thus, the PtCl42? ion is displaced from PDPMT‐Cl and the fluorescence of PDPMT‐Cl is recovered. By triggering the “turn‐on” signal of PDPMT‐Cl, it is successful to detect the protein in real time. “Turn‐on” response as readout signal is able to effectively reduce background noise and increase detection sensitivity. This method offers good selectivity for detecting protein in the presence of other common amino acids and metal ions. Under optimized conditions, the concentration of BSA in the range of 0.0004–1.75 mg/mL exhibits a linear relationship with the relative fluorescence intensity, and the correlation coefficient is 0.9997. The limit of detection is 4.47 × 10?4 mg/mL. The system is successfully applied for detecting protein in milk and egg. Due to the simplicity, sensitivity, and rapid response, this assay shows great potential for protein detection in the future. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 939‐943, 2013  相似文献   

7.
Direct mixing of cellulose triacetate (CTA) in acetone at room temperature produces only an opaque swollen gel at all concentrations. However, cycling the mixture between room temperature and ?78 ± 3°C results in a stable solution at room temperature, if the concentration is less than 6% (w/w). This process has been called “cold‐solutioning.” Such a process also produces a clear solution at concentrations between 6% (w/w) and 10% (w/w); however, in time, the solution separates slowly into at least two phases, a clear liquid and an opaque gel phase. At concentrations above 10% (w/w) and below 20% (w/w), the system exhibits two phases. A completely opaque swollen gel forms at concentrations of 20% (w/w) and above. The above‐described cold‐solutioning phenomena are shown to be the coupled kinetic and thermodynamic consequences of (1) the large thermal stresses that would result from thawing a swollen mixture of CTA and acetone, arising from the large differences in their thermal expansion coefficients; and (2) the “bimodal” composition of the cellulose derivative. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1697–1707, 2003  相似文献   

8.
Beer-Lambert's law has a wide range of applications, spanning the fields of pure sciences and engineering, and is commonly used for the determination of the concentration of an optically sensitive compound, at “low” concentrations. In this report it is shown that a log-log expression, log(T/T0) = K log(C/C0), accurately models experimental data (±3%) for four different absorbing species, at “high” concentrations. The dimensionless constant K is shown to be only a characteristic of the absorbing species, and independent of the spectrophotometer/cuvette system used. The new equation is used for on-line monitoring of dynamic biomass concentration in a continuous bioreactor (CSTBR) for a step change in dilution rate.  相似文献   

9.
Experiments are described for the addition of 1,2-diphenylhydrazine to dimethyl allene-1,3-dicarboxylate and the subsequent conversion of dimethyl 3-(1,2-diphenylhydrazino)pent-2-enedioate (3) to either the pyrazolone (4) or a mixture of the indole (5) and the pyrazolone (4).  相似文献   

10.
A special “pore/bead” membrane was prepared with a mesoporous inorganic filler (MCM‐41) and a P(VDF‐HFP) binder. The special “pore/bead” structure of the MCM‐41 filler not only enhanced the puncture strength of the membrane but also improved its ionic conductivity. The puncture strength of the dried “pore/bead” membrane (MCM‐41 : P(VDF‐HFP) = 1 : 1.5) was 18 N, and showed a slight decrease (16 N) after the membrane was wetted by liquid electrolyte. Additionally, the composite membrane showed excellent thermal dimensional stability. The composite membrane could be activated by adding 1M LiClO4‐EC/DMC (1 : 1 by volume). The activated membrane displayed a high ionic conductivity about 3.4 × 10?3 S cm?1 at room temperature. Its electrochemical stability window was up to 5.3 V vs. Li/Li+, indicating that it was very suitable for lithium‐ion battery application. The battery assembled using the composite electrolyte also showed reasonably good high‐rate performance. The approach of preparing a “pore/bead” membrane provides a new avenue for improving both the conductivity and the mechanical strength of polymer electrolytes for lithium batteries. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

11.
The molybdate‐catalyzed “dark” singlet oxygenation of hydrophobic compounds with hydrogen peroxide proceeds efficiently with low catalyst loadings (10 –3 mol %) in chlorine‐free w/o microemulsions. These micro‐heterogeneous systems are composed of sodium dodecyl sulfate (SDS)/n‐butanol/water/organic phase, the latter being either a ”green” solvent such as ethyl acetate or a liquid substrate, such as α‐terpinene or β‐citronellol. Very high reactor yields with improved product/SDS ratio can be obtained for the ”dark” singlet oxygenation of such liquid substrates.  相似文献   

12.
Physiological Actions of “Oxidized Fatty Acids” from Blown Oils Feeding experiments were carried out on 60 rats for 189 days using “oxidized fatty acids” which were isolated by the DGF-method C-III 3 (53). The “oxidized fatty acids” corresponded to oxy-dimeric linoleic acid with respect to molecular weight and elemental formula. The investigations included weight gain of the experimental animals, histological examination of the internal organs, and composition of depot and cellular fats. The results of these studies are reported. Growth retardations were observed as a clear indication of harmful action of “oxidized fatty acids”.  相似文献   

13.
The aim of this work was to ascertain the amount of oxidized triglycerides and triglyceride dimers in virgin and “lampante” olive oils: to this effect, 38 samples were collected from different oil-mills. No data on the above compound classes in ?lampante”? olive oils have ever appeared in literature up to now. However, fat autoxidation is known to imply polymerization reactions; so, low amounts of oligopolymers may be formed in oil at a given state of oxidation. This aspect also applies to virgin olive oils because the very few data reported in literature are mainly related to extra virgin olive oils which are classified as high quality oils. Column chromatography and high-performance size exclusion chromatography were used for oil analysis in this work. Triglyceride dimers were either absent or present in traces in virgin olive oils, but were found in ?lampante”? oils with a mean value of 0.07%. Oxidized triglyceride percentages in ?lampante”? oils were more than twice as high as those present in virgin oils. The data obtained suggest the following consideration: the presence of dimers in vegetable oils reveals a rather high oxidation level and is confirmed by the higher oxidized triglyceride values. This is a reliable index of oxidative degradation in oil.  相似文献   

14.
艾小红  杨世柱  萧丽梅 《化学试剂》2006,28(3):167-168,184
以正丁醛杯[4]芳烃母体化合物1与溴乙酸乙酯反应,得到杯[4]芳烃醚2,再与9-蒽甲醇进行酯交换反应,得到目标化合物3。对化合物2和目标化合物3的结构进行了熔点、红外光谱、核磁共振谱的表征。  相似文献   

15.
N‐Phenyl‐3‐substituted 5‐pyrazolone derivatives were investigated as organic photostabilizers for rigid poly(vinyl chloride) (PVC). Their stabilizing efficiency was evaluated by the determination of the weight loss of the polymer after irradiation for different periods and by the determination of the amount of gel formation as well as the intrinsic viscosity of the soluble fraction of the degraded polymer. Moreover, the efficiency was evaluated from the extent of the discoloration of the degraded polymer. This was attributed not only to the radical trapping potency of the pyrazolone derivatives, which intervened with the radical degradation species in the degradation process of PVC, but also to the blocking of the newly formed radical sites on the polymeric chains. Their stabilizing efficiencies were compared with those of phenyl salicylate and 2‐hydroxy‐4‐(octyloxy)phenyl benzophenone, industrially known UV absorbers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1543–1555, 2006  相似文献   

16.
ω-Cyanoacetophenone was coupled with a variety of aromatic diazonium chlorides to give the corresponding arylazo derivatives 1 a – g . Analysis of the IR and UV spectra of these compounds indicated that they exist mainly as the corresponding arylhydrazones. Compounds 1 a – d, f, g reacted with diazomethane to yield the N-methyl-arylhydrazones 2 a – f . 3-Amino-4-arylazo-5-phenylpyrazoles 5 a – g and 4-arylazo-5-imino-1,3-diphenyl-2-pyrazolines 6 a – g were obtained by the interaction of 1 a – g with hydrazine hydrate and with phenylhydrazine, respectively.  相似文献   

17.
The synthesis of electrically Conducting Natural Rubber (CNR) nanoparticles from natural rubber (cis 1, 4 polyisoprene) by a simple chemical doping technique is reported for the first time. Much before the establishment of conjugation as a precondition for polymers to be conducting a typical nonconjugated polymer like cis 1,4 polyisoprene was shown to develop intrinsic conductivity on doping. However, the possibility of developing conducting nanoparticles of natural rubber by doping has never been explored. Doping of natural rubber solution with Antimony pentchloride is found to lead to the formation of nanosized rubber particles with improved thermal stability and lower degradation characteristics than that of pristine rubber. Transmission electron microscopy and Dynamic Light Scattering experiments revealed a highly uniform dispersion of the particles with sizes in the range of 4 nm. The doped nanoparticles are found to retain “rubbery” properties of natural rubber and therefore these can be rightly termed as Rubber Nano particles. The development of nanoparticles of rubber assumes great significance in that it would lead to hitherto unknown applications for natural rubber in micro applications‐like sensors, and optoelectronics devices to macro applications such as compatible reinforcing fillers for elastomers and plastics to replace conventional fillers like carbon particles. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

18.
4-Benzyl-2-1(2H) phthalazonyl derivatives of type 2, 3, 5a, b were synthesized by Mannich reaction of 4-benzylphthalazinone 1 which by the reaction with diazomethane yielded O-methylated derivative 4 . Various 1-benzal-2-substituted aryl-3(2H) isoindolinones 7a–f, 8a–e were also prepared. Its i.r., 1H-n.m.r. and mass spectra were discussed. Some of them exhibit pronounced antimicrobial activities. A number of phthalazinones have found application in clinical medicine [1–3] due to the their pronounced antipyretic, analgesic and tuberculostatic activity and the importance of some benzylidenephthalimidines as stabilisers for halogen containing high polymers [4] and the local anesthetic activity superior to that of procaine [5], tempted us to procure some new phthalazinones and isoindolinones with biological interest.  相似文献   

19.
Carboxyl‐functionalized magnetic nanogel was synthesized by facile “green” photochemical method. A possible mechanism of photochemical synthesis was proposed. Effects of irradiation time and volume of monomer dropped on the hydrodynamic diameter of the magnetic nanogel were investigated by photo correlation spectroscopy. The image of atomic force microscopy presented that the magnetic nanogel was with loosed structure. X‐ray diffraction analysis showed that UV irradiation did not induce phase change of Fe3O4. Superparamagnetic behaviors were retained for Fe3O4 while slightly reducing the value of saturation magnetization for surface coating. High magnetic content of (as high as 85%) and strong magnetization of Fe3O4 guaranteed that the magnetic nanogel was susceptive to external applied magnetic field. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   

20.
Mirror-symmetric Hexahydro-1,2,4,5-tetrazines from Pyrazolidine-3-one-N,N-betaines—a Contribution to the „Thermal Dimerization”︁ of 1,3-Dipoles Chemical reactions, i.r., 1H-n.m.r., and 13C-n.m.r. data show that the “thermal dimers” of pyrazolidine-3-one azomethinimines 2 , which till now accidentally formed during the synthesis of 2 from pyrazolidine-3-ones 5 and aldehydes 6 , are 5,11-diaryl-perhydro-dipyrazolo[1,2-a; 1′,2′-d][1,2,4,5]-tetrazine-1,9-diones 3 , i.e. mirror-symmetric hexahydro-1,2,4,5-tetrazines with (C-5) and (C-11) placed on the mirror plane. From DREIDING models and from the nonequivalence, concerning 13C-n.m.r., of the pairs of carbon atoms in the o- resp. m-positions of the aryl substituent I at (C-5) of the “dimers” 3 is derived that the rotation of I is sterically hindered (ΔG = 16,3 kcal/mole for 3b ), and that the preferred arrangement of I is perpendicular to the plane of the hexahydrotetrazine ring. The “thermal dimerization” of the 1,3-dipoles 2 is a complex series of two addition and elimination steps proceeding in the presence of catalytical amounts of pyrazolidine-3-one 5 and of H. The mechanism is rationalized, consequences are suggested concerning known “dimerizations” of 1,3-dipoles.  相似文献   

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