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1.
The polymerization of n-butyl methacrylate was investigated using the Atom Transfer Radical Polymerization technique with CuBr and CuCl/N,N,N′,N″,N″-pentamethyldiethylenetriamine catalytic systems. Various combinations of catalyst systems and initiators were utilized in order to optimize the polymerization conditions and to obtain well-defined polymers (i.e. controlled molecular weights and low polydispersities). It has been found that the optimal initiator for this system is a chlorine-based initiator, when the catalyst used is a Cu(I) salt in conjunction with the N,N,N′,N″,N″-pentamethyldiethylenetriamine ligand. Bromine-based initiators tend to result in large amounts of initial termination, leading to polymers with less than ideal chain end functionality, even if CuCl is used as the Cu(I) species to invoke the halogen exchange. Additionally, the effects of the polymerization temperature, copper(1) species and the initiator structure were determined.  相似文献   

2.
3.
Ethyl 2-methyl-11-oxo-9, 10-dihydro-1 H , 11 H -pyrido[4",3":4',5']thieno[2',3':4,5]pyrimido[2,1-b][1,3,4]thiadiazine-8(7 H )-carboxylate 7 has been synthesised by the reaction of ethyl 3-amino-4-oxo-2-thioxo-1,3,4,5,6,8-hexahydropyrido[4',3':4,5]thieno[2,3-d]pyrimidine-7(2 H )-carboxylate 2 with allylbromide followed by treatment with bromine and subsequent dehydrobromination of the brominated product 5 with ethanolic sodium hydroxide. Its isomeric ethyl 2-methyl-11-oxo-9,10-dihydro-3 H ,11 H -pyrido[4",3Prime;:4',5']thieno[2',3':4,5]pyrimido[2,1-b][1,3,4]thiadiazine-8(7 H )-carboxylate 8 has been obtained by condensation of 2 with chloroacetone followed by cyclization of the intermediate 9 with p -toulenesulfonic acid. The thiadiazino derivatives 11 , 13 , 15 were prepared through the reaction of 2 with the appropriate f -halocarbonyl compounds followed by cyclization reactions of the intermediates 10 , 12 , 14 .  相似文献   

4.
The title macrocycle 1 was synthesised in good yield (66%) by a one-pot condensation process from 2,3-bis(chloromethyl)-p-xylene andN,N-ditosylethylendiamine. The macrocycle was found to undergo isomerization processes at elevated temperature on the NMR time scale (G = 87.8 kJ mol–1) and acts as a suitable host only for toluene. The FAB-MS spectra of1 is rich, and full of interesting and very diagnostic fragmentation pathways.  相似文献   

5.
The 1,3‐dipolar cycloaddition of an azomethine ylide, generated from isatin and sarcosine by a decarboxylative route with various p‐substituted 3,5 bis(aryl methylidene)N‐methyl‐4‐piperidinones in refluxing methanol, proceeded regioselectively to give novel dispiroheterocycles. The product on subsequent annulation with hydrazine hydrate afforded 1‐N‐methyl‐spiro[2.3′]oxindole‐spiro[3.7″](3″‐aryl)‐5″‐methyl‐3″,3a″,4″,5″,6″,7″‐hexahydro‐2H‐pyrazolo[4,3‐c]pyridine‐4‐aryl‐pyrrolidines in good yield.  相似文献   

6.
4-Methyl-2-phenyl-5-(1-pyrryl)-6-substituted-thieno[2,3-d]pyrimidines ( 3a-c , 4a-c , 5a , b , and 6 ) have been synthesized. Some of the substituents in position 6 were used to build up different sulfur-, nitrogen- and/or oxygen-containing heterocyclic rings at that position. The 4-methyl-2-phenyl-5-(1-pyrryl)-thieno[2,3-d]pyrimidine-6-carboazide ( 20 ) was also used as a key intermediate in the synthesis of the target pyrrolo[1",2":1',6']pyrazino[2',3':4,5]thieno[2,3-d]pyrimidines.  相似文献   

7.
详细报道了Nafion-聚[N',N"-(1,3-丙二亚甲基)双(1,2-苯二氨基)-N,N,N′,N″,N′″']合镍[PolyNi(Ⅱ)L]修饰微铂电极的制备及性质,实验表明,该修饰电极对NO有较高的灵敏度和选择性.当NO的浓度在2.0×10-7~1.6×10-5 mol/L 范围内峰电流与NO的浓度呈线性关系,相关系数r=O.994.用于血液中NO的检测,效果良好.  相似文献   

8.
Here, we report a CO2 stimulus-responsive system with anionic surfactant sodium oleate (NaOA) and N, N, N′, N′, N″-Pentamethyldipropylenetriamine (PMDPTA). The microstructure transition from spherical micelles to worm-like micelles was confirmed by rheology measurements, dynamic light scattering (DLS), and cryogenic transmission electron microscopy (Cyro-TEM). There were three types of CO2?responsive groups in PMDPTA. However, because of PMDPTA ionization degrees, just one responsive group of PMDPTA could be ionized by CO2 to work with OA?, resulting in structure transformation from spherical micelles to worm-like micelles. Besides, this system could be switchable between low-viscosity fluid and high viscoelastic by CO2/N2.  相似文献   

9.
详细报道了Nafion-聚[N′,N″-(1,3-丙二亚甲基)双(1,2-苯二氨基)-N,N′,N″,N]合镍[PolyNi(Ⅱ)L]修饰微铂电极的制备及性质.实验表明,该修饰电极对NO有较高的灵敏度和选择性.当NO的浓度在2.0×10-7~1.6×10-5mol/L范围内峰电流与NO的浓度呈线性关系,相关系数r=0.994.用于血液中NO的检测,效果良好.  相似文献   

10.
Abstract

The kinetics of aqueous polymerization of N,N′-methylenebisacrylamide (N,N′ -MBA) was studied under an inert atmosphere within the 20-40°C temperature range. The rate of polymerization was found to be proportional to N,N′ -MBA and square-root dependent to the concentration of Ag+ and peroxidiphosphate. An intramolecular cyclization prior to propagation is proposed in the mechanism to explain the kinetic data. The overall energy of activation has been found to be 30.2 ± 0.1 kJ · mol?1. On the basis of experimental results, a suitable scheme has been proposed and a rate expression has been derived.  相似文献   

11.
N ,N′ ,N″ ,N 四对甲苯磺酰 1,4,7,10 四氮杂环十二烷是Atkins法合成 1,4,7,10 四氮杂环十二烷的关键中间体 ,但其水解脱磺酰基比较困难 ,常规水解一般需要采用 96%~ 98%硫酸在 14 0℃左右加热 2~ 3d .报道了一种微波促进快速水解法 ,即在稍加改装或未改装的家用微波炉中 ,采用 95 %~ 98%硫酸 ,控制火力 2~ 5档 ,全对甲苯磺酰化全氮冠醚仅需5 0~ 12 0s即可完成水解 ,比常规加热水解所需时间缩短约 3 0 0 0~ 80 0 0倍 ,浓硫酸用量也比常规加热水解少 ,收率较常规水解高 .  相似文献   

12.
Two isoflavone 7-O-α-4″-anhydro-4″,5″-didehydroglucuronides, namely daidzein 7-O-α-4″-anhydro-4″,5″-didehydroglucuronide (1) and genistein 7-O-α-4″-anhydro-4″,5″-didehydroglucuronide (2), were isolated and identified from the mutant strain of Streptomyces sp. LZ35ΔgdmAI. Their structures were elucidated by the analysis of their high resolution mass spectrometry (HR–MS) and 1D, 2D Nuclear magnetic Resonance (NMR) spectroscopic data. They are new natural products and maybe the transformed products of the soybean meal by Streptomyces sp. LZ35ΔgdmAI.  相似文献   

13.
二亚乙基三胺与对—甲苯磺酰氯在碳酸钾存在下,发生对甲苯磺酰化反应,生成N,N′,N″-三(对—甲苯磺酰基)二亚乙基三胺,产率96%。考察影响反应的几个因素。  相似文献   

14.
A new tripodal P,N ligand (C63H48N3O3P3) was prepared and characterized by elemental analysis, IR and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 13.013(3), b = 28.406(6), c = 14.911(3) A^°, β= 111.04(3)°, V= 5144.6(18) A^°^3 Z = 4, Dc = 1.276 g/cm^3, Mr = 987.95, λ(MoKa) = 0.71073 A^°,μ = 0.17 mm^-1, F(000) = 2064, R = 0.0786 and wR = 0.1545. A total of 43260 unique reflections were collected, of which 5112 with I 〉 2σ(I) were observed. The title compound has a central benzene ring, which is linked by -NH-CO- bonds to three 2-aminophenyltriphenylphosphium moieties, of which two with P(1) and P(2) centers are pointing to the same face of the central aryl ring, while the third one directs oppositely, forming a pseudo-propeller. In the crystal structure, there exist face-to-face π-π stacking interactions which increase the stability of the crystal structure.  相似文献   

15.
《Polyhedron》1999,18(8-9):1147-1152
A new bis(amide) derivative of diethylenetriamine-N,N,N′,N″,N″-pentaacetic acid (H5dtpa), diethylenetriamine-N,N′,N″-triacetic-N,N″-bis(2-methoxyphenethylamide) (H3L), has been synthesized. The crystal structure of gadolinium(III) complex of H3L ([GdL]) has been determined by X-ray crystallography. The coordination sphere of Gd(III) comprises three amine nitrogens, two amide oxygens, three carboxylic acid oxygens, and one water molecule. 17O NMR shifts showed that the [DyL] complex had one inner-sphere water molecule. Relaxivity studies with the gadolinium(III) complex showed that they associate strongly with proteins leading to a significant relaxivity enhancement.  相似文献   

16.
Zusammenfassung Gemischt substituierte Disilylamine (RRRSi)2NH lassen sich von NaNH2 zu reaktionsfähigen Natrium-bis-(silyl)-amiden metallieren, aus denen nach Umsetzung mit Organohalogensilanen und anschließender Alkoholyse der verbleibenden Si-Cl-Gruppen gemischt substituierte Trisilylamine (RRRSi)3N mit R=(me), R, R=O(me); R,R=(me), R=O(et); R=(vi), R, R=O(me); R=(me), R=(vi), R=O(ipr) dargestellt werden konnten.33. Mitt.:U. Wannagat, J. Pump undH. Bürger, Mh. Chem.94, 1013 (1963).Auszüge aus den DissertationenH. Bürger, TH Aachen 1962,P. Geymayer, TH Graz 1963, und der DiplomarbeitG. Torper, TH Graz 1962; vgl. auchU. Wannagat undH. Bürger, Angew. Chem.75, 95 (1963).  相似文献   

17.
Under microwave irradiation,2,2'-alkoxy-bridging or 4,4'-alkoxy-bridging dibenzaldehydes reacted with 4-hydroxycoumarin in DMF to give a series of 3,3',3″,3'″-o-and 3,3',3″,3'″-p-phenylenedimethylidinetetrakis-(4-hydroxy-2H-1-benzopyran-2-ones) in moderate yields.The structures of the synthetic coumarin derivatives were characterized with IR,1H NMR and MS spectroscopy as well as X-ray single crystallography.  相似文献   

18.
Three new carbacylamidophosphates with formula CHnCl3?nC(O)NHP(O)(NHCH(CH3)2)2 (n = 2 (1); n = 1 (2); n = 0 (3)) and their organotin compounds with formula (1)SnCl2Me2(μ-1)SnCl2Me2 (4), SnCl2Me2(2)2·C6H5CH3 (5) and [SnCl2Me2(3)]n (6) were synthesized and characterized by elemental, IR and NMR spectra analyses. The spectroscopic properties of complexes were compared with those corresponding ligands. The crystal structures of complexes were determined by X-ray crystallography, which reveals that complex 4 is binuclear structure with two non-equivalent Sn atoms. One adopts a distorted trans(C,C) cis(OP,OP) cis(Cl,Cl) octahedral configuration, while the other adopts a distorted trigonal bipyramidal geometry composed of two methyl groups, two chlorine atoms and carbonyl group. Molecule 5 is centrosymmetric with two OP, disordered chlorine and methyl groups in trans positions. Toluene molecules are located in the interlayer spaces of 5. In compound 6, bonding via both PO and CO functionalities forms 1D infinite chain structures along b axis. The Sn–OP bond length in 6 is significantly longer than the same distance in 4 and 5, while the OP and Sn–Cl bonds are shorter. The bond lengths in these complexes were compared with those of N-benzoyl carbacylamidophosphates.  相似文献   

19.
Summary Cobalt(II) and copper(II) complexes of the title ligand, TCEC, as well as a cobalt(II) complex ofN,N,N",N'-tetra (1-methyl-2-cyanoethyl)-1,4,8,11-tetraazacyclotetradecane, TMCEC, have been isolated and spectrally characterized.  相似文献   

20.
Three new carbacylamidophosphates with formula CHnCl3−nC(O)NHP(O)(NHCH(CH3)2)2 (n = 2 (1); n = 1 (2); n = 0 (3)) and their organotin compounds with formula (1)SnCl2Me2(μ-1)SnCl2Me2 (4), SnCl2Me2(2)2·C6H5CH3 (5) and [SnCl2Me2(3)]n (6) were synthesized and characterized by elemental, IR and NMR spectra analyses. The spectroscopic properties of complexes were compared with those corresponding ligands. The crystal structures of complexes were determined by X-ray crystallography, which reveals that complex 4 is binuclear structure with two non-equivalent Sn atoms. One adopts a distorted trans(C,C) cis(OP,OP) cis(Cl,Cl) octahedral configuration, while the other adopts a distorted trigonal bipyramidal geometry composed of two methyl groups, two chlorine atoms and carbonyl group. Molecule 5 is centrosymmetric with two OP, disordered chlorine and methyl groups in trans positions. Toluene molecules are located in the interlayer spaces of 5. In compound 6, bonding via both PO and CO functionalities forms 1D infinite chain structures along b axis. The Sn–OP bond length in 6 is significantly longer than the same distance in 4 and 5, while the OP and Sn–Cl bonds are shorter. The bond lengths in these complexes were compared with those of N-benzoyl carbacylamidophosphates.  相似文献   

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