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1.
The organisation and phase transition of single crystals containing three isostructural bis[6-O,6-O'-(1,2:3,4-diisopropylidene-alpha- D-galactopyranosyl)thiophosphoryl] dichalcogenide derivatives: disulfide 1, diselenide 2 and mixed seleno-sulfide 3, was deduced upon 1D, 2D and variable temperature 31P NMR experiments.  相似文献   

2.
林景祥  曹荣 《中国科学B辑》2009,39(3):275-280
合成了六元瓜环与链状烷基二胺(1,2-乙二胺)形成的超分子化合物.采用X射线衍射技术测定了其晶体结构,并得到元素分析、热重、红外光谱的佐证,揭示了主客体相互作用的模式.还采用^1HNMR技术研究了溶液中六元瓜环与乙二胺的超分子相互作用.研究表明,在不同的环境下瓜环与客体采取相异的超分子作用模式,晶体结构中显示一个六元瓜环的两个端口通过离子偶极作用以不同的作用模式分别跟两个乙二胺客体分子形成一个三单元组成的超分子作用实体;而在溶液中瓜环与乙二胺的相互作用模式与晶体中的不同.  相似文献   

3.
Bis[6-O,6-O'-(1,2:3,4-diisopropylidene-alpha-D-galactopyranosyl) thiophosphoryl] disulfide shows a strong tendency to form inclusion compounds. The crystal and molecular structure of eight different solvates was established by X-ray analysis. The results indicate three different types of disulfide arrangements in the crystal lattice. By means of 31P CP/MAS NMR experiments the principal values delta 11, delta 22, and delta 33 of the 31P chemical shift tensor were obtained for each form. The orientation of its principal axes with respect to a molecular frame was investigated by means of 31P CP and single-crystal NMR for the complex with propan-2-ol. The principal axis 1 of both chemically equivalent phosphorus atoms is nearly parallel to the P-S bond and the principal axis 3 is very close to the P=S bond. DFT GIAO calculations of the model compound (EtO)2(S)P1SSP2(S)-(OEt)2 allowed assignment of the experimental chemical shift curves to the magnetically nonequivalent atoms P1 and P2. The maximum difference between calculated angles [symbol: see text] i-P-X)calcd and experimental angles [symbol: see text] i-P-X)exptl is 8.3 degrees and the rms distance 3.8 degrees (i = principal axes 1, 2, 3; X = S, -S-, -O1-, -O2-). The influence of C-H...S weak hydrogen bonding on phosphorus shielding was tested theoretically (31P DFT GIAO) employing the dimethoxythiophosphoryl disulfide.CH4 complex as a model compound. The sensitivity of 31P delta ii parameters to intermolecular forces is demonstrated.  相似文献   

4.
A facile method for the synthesis of pillar[6]arenes was developed.A series of pillar[6]arenes were prepared with FeCl 3 as catalyst and chloroform as solvent at room temperature in moderate yields(30%-40%).Their host-guest properties with n-cetyltrimethyl ammonium bromide were investigated by 1 HNMR.The results showed that high selectivity in the host-guest relationship became apparent between pillar[6]arenes and pillar[5]arenes based on the different size of the inner cavity.  相似文献   

5.
6.
Abstract

Polyoxomolybdate-based organic?inorganic hybrid architectures were synthesised and characterised by X-ray crystallography. The supramolecular assemblies present rows of metallic clusters H-bonded by ammonium cations, with a 1:2 molybdate/ammonium ratio. The organic moieties of the ammonium cations establish hydrophobic contact among them such as van der Waals, C–H?π and π?π interactions that stabilise the supramolecular architectures. In particular, for compound 5 the n-alkyl tails pack closely together giving a lipid-like bilayer. In compound 6, the aromatic phenyl rings of the organic cation allow the stabilisation of the supramolecular architecture by C–H?π and π?π interactions. Regarding the X-ray structure of the compound 11, the tetraanionic octa-molybdate [Mo8O26]4? cluster is surrounded by four ethyl-triphenyl-phosphonium cations. Running along the b-axis open channels are occupied by DMF solvent molecules. Interestingly, a soaking experiment in n-pentane with the corresponding crystals of compound 11 afforded to a crystal structure very different from the native one.  相似文献   

7.
8.
利用1,4-二溴丁二酮(1)分别与3-烷基/芳基-4-氨基-5-巯基-1, 2,4-三唑(2a-2n)反应,合成了14种新的双-(3-烷基/芳基)-7H-1,2, 4-三唑并[3,4-b]-1,3,3-噻二嗪类化合物(3a-3n),并利用EA、IR,~1H NMR和MS确定了其结构。  相似文献   

9.
10.
By the action of thionyl chloride on 3(5)-R-4-phenacylpyrazole-5(3)-carboxylic acid ( 3c,d ), 3-R-5-phenylpyrano[3,4-c]pyrazole-7-(1H)ones ( 4c,d ) were obtained. When 4c,d were treated with hydrazine hydrate followed by refluxing in ethanol containing acetic acid, 4,7-dihydro-3-R-5-phenylpyrazolo[3,4-d][1,2]-diazepin-8-(1H)ones ( 6c,d ) were formed. Compounds 6c,d , in turn, were refluxed in ethanol saturated with hydrochloric acid to yield 6-amino-1,6-dihydro-3-R-5-phenyl-7H-pyrazolo[3,4-c]pyridin-7-ones ( 7c,d ). Compounds 7c,d could be obtained directly from 5c,d. The starting materials 3c,d were prepared by hydrolysis of the oxime of 3(5)-R-4-phenacyl-5(3)carboalcoxypyrazoles ( 1a,b ). Structural assignments rested on correct elemental analysis, molecular weights determined by mass spectrometry, and spectroscopic evidence.  相似文献   

11.
3,5-Disubstituted 4,5-dihydroindeno[1,2-c][1,2]diazepin-6 (1H)-ones ( 3a–g ) were obtained in 29–72% yields by condensing 2-(substituted-2-acylethyl)-1,3-indandiones ( 1a–n ) with hydrazine. The NH group of the indenodiazepinones 3a–g is quite unreactive. Two methods based on the Michael reaction were used for preparing the acylethylindandiones 1a–n : one from 1,3-indandione and chalcone-type compounds and the other from 2-benzylidene-1,3-indandione and acetophenones. The latter method was found more practical and of more general application.  相似文献   

12.
13.
CrystalandMolecularStructureofN-Isopropyl-O-(p-Chlorophenyl)-O'-(1,2:3,4-Di-O"-isopropylidene-α-D-galactopyranosyl)Thiophosph...  相似文献   

14.
15.
Two dimers (2 and 3), dendritic tetramer (4), hexamer (5), and decamer (6) of benzo[1,2-b:3,4-b':5,6-b']trithiophene (BTT), a potential π-core unit with C(3h) symmetry, were synthesized, characterized, and evaluated for possible use as organic semiconductors. Single crystal X-ray analyses of the dimers (2 and 3) revealed that they have planar molecular structures with dihedral angles of almost 180° between two BTT units. In accordance with the rigid and planar molecular structure, the unsubstituted dimer (2) is poorly soluble, whereas the octyl-substituted dimer (3) has improved solubility. Although the solubility of the dendritic tetramer (4) is decreased, further extended systems, i.e., the dendritic hexamer (5) and decamer (6), have solubilities better than that of 4. With increasing numbers of BTT units in the molecule, the experimentally determined energy levels of HOMO shift upward slightly and the HOMO-LUMO energy gaps become smaller, but the extent of HOMO destabilization and reduction of the HOMO-LUMO gap are not significant. Taking into account the energy levels of the frontier orbitals, 3-6 could be useful as p-channel organic semiconductors rather than n-channel. In fact, the spin-coated thin film of 3 with edge-on molecular orientation acted as an active channel of field-effect transistors that showed hole mobilities as high as 0.14 cm(2) V(-1) s(-1), indicating that the BTT core is a useful π-conjugated system for application to organic semiconductors, although 4-6 gave FET characteristics rather inferior to those of 3, owing to their amorphous nature in the thin film state.  相似文献   

16.
17.
《Mendeleev Communications》2023,33(2):164-166
Acetylene reacts with 2-aminopyridines in the superbase system KOBut/DMSO (the initial acetylene pressure ∼8 atm, 80 °C, 5 min) to give 2,3-dimethylimidazo[1,2-α]-pyridines in up to 60% yields. In the case of 2-amino-5-chloropyridine, along with ‘normal’ product, (Z)-5-chloro- N-[2-(2,3-dimethylimidazo[1,2-α]pyridin-6-yl)vinyl]pyridin-2-amine is formed in 40% yield. These multi-molecular assemblies involve parallel nucleophilic addition of N-centered anions to the triple bond and ethynylation of the forming C=N bond.  相似文献   

18.
ω-溴代芳香基乙酮与3-(D-葡萄糖-1-基)-4-氨基-5-巯基-1,2,4-三唑反应 合成了一系列新颖的3-(D-葡萄糖-1-基)-6-芳基-7H-1,2,4三唑并[3,4-b[1,3 ,4]噻二嗪.用元素分析,IR,NMR,MS对其结构进行了表征,研究了其NMR波谱特 征,并以^1H-^1H COSY,^13C-^1H COSY,COLOC二维NMR技术对其^1H NMR,^13C NMR的谱峰进行了全归属  相似文献   

19.
Three 2,4-diamino-l(), 11-dihydro-9H-benzo[3,4]cyclohepta[ 1,2-d]pyrimidines (6a-6c) representing the first examples of a new ring system were synthesized from 2-benzosuberones and cyanoguanidine. Similarly, 2,4-diamino-6,7-dihydro-5H-benzo[3,4]cyelohepta[2,1-d]pyrimidine ( 24 ) was prepared from 1-benzosuberone. The ultraviolet spectral properties of these compounds were examined with reference to those of the analogs in which the central ring is five- and six-mernbered.  相似文献   

20.
Phenacyl-malononitrile derivatives 1a,b react with dimethyl formamide dimethyl acetal (DMFDMA) in refluxing toluene to afford the enaminones 2a,b respectively. Compounds 2a and 2b react with the aromatic amines (aniline, p-toluidine, p-anisidine) in refluxing ethanol to afford the pyrroles 4af and with anthranilonitrile and methyl anthranilate to afford the pyrrolo[1,2-a]quinazolines 5a,b and 6a,b respectively. The pyrrole derivatives 4af react with hydrazine hydrate and phenyl hydrazine in refluxing ethanol to afford the pyrrolo[3,4-d] pyridazine derivatives 7af and 8af respectively.  相似文献   

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