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141.
1,4,6-Trisubstituted 3,6-dihydro-2-(1H)pyrimidinones (Ia-d) easily underwent the ring opening reaction with hydroxylamine hydrochloride to afford the oximes (IIa-d) in good yields. In the case of 3,6-dihydro-6-methyl-I-phenyl-2-(1H)pyrimidinone (Ie), 2-anilinobutyronitrile (III) was obtained in addition to the oxime (IIe). Dihydro-2-(1H)pyrimidinone (IV) and -thiones (V and VI) did not undergo the ring opening reaction.  相似文献   
142.
Reduction of indolin-2-ones with lithium aluminium hydride (LAH) or diisobutylaluminum hydride (DIBAL) and desulfurization of indoline-2-thiones with Raney-Ni were investigated. Treatment of indoline-2-ones 1 with LAH or DIBAL yield indoles 4 and/or indolines 3 in moderate-to high yield depending on the substituents at N and C(3) of 1 . Indoline-2-thiones 2 were desulfurized with Raney-Ni to give indoles 4 and/or indolines 3 .  相似文献   
143.
X-ray diffraction measurements for 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid ([BMIM][PF6])-CO2 systems were carried out at high pressures with a newly developed polymer cell. The intermolecular distribution functions (g(inter)(r)) were obtained at 25 degrees C for neat [BMIM][PF6] and its solutions saturated with CO2 at 4 and 15 MPa, where the mole fractions (x) of CO2 correspond to 0.5 and 0.7, respectively. In g(inter)(r) for x = 0.5, two peaks appeared at around 2.8 and 3.2 A. These two peaks in g(inter)(r) appreciably increased for x = 0.7; moreover, there was another peak observed at approximately 3.8 A. Only assuming the correlations between CO2 and [PF6]-, it is reasonably determined that the nearest-neighbor P([PF6]-). . .C(CO2) distances are 3.57 and 3.59 A with the coordination numbers being 1.8 and 4.0 for x = 0.5 and 0.7, respectively. It is concluded that CO2 molecules are preferentially solvated to the [PF6]- anion.  相似文献   
144.
新型簇合物(n-Bu4N)2[Fe4S4(tpbt)4](tpbt=2,4,6-三苯基苯硫酚基)通过2,4,6-三苯基苯硫酚和(n-Bu4N)2[Fe4S4(S-t-Bu)4]在DMF(二甲基甲酰胺)中进行配体交换反应合成得到。该簇合物在CH相似文献   
145.
The Hofmann-danon-typeo-xylene clathrate Cd[NH2(CH2)9NH2]Ni(CN)4·0.5(CH3)2C6H4, crystallizes in the triclinic space groupP witha = 15.118(3),b = 14.048(4),c = 7.325(1) Å, = 91.50(2), = 131.66(3), and = 107.50(2)°,V = 1051(1) Å3 andZ = 2. The structure, refined toR = 0.047 using 2851 reflections, reveals a three-dimensional host framework built of the layers of a two-dimensionalcatena-[cadmium tetra--cyanonickelate(Il)] network and of the ambidentate 1,9-diaminononane (danon) bridging the Cd atoms in adjacent networks. The guesto-xylene molecule is accommodated in the cavity formed in the interlayer space similar to that in the Hofmann-daotn-type. The skeleton of the danon in the Cd-NC9N-Cd linkage takes a (gauche)2(trans)8 conformation twisted at the (gauche)2 part in contrast with the all-trans conformation of 1,8-diaminononane in the Hofmann-daotn-type clathrate. The twisted (gauche)2 part of the danon skeleton occupies the interlayer space to such an extent that void space available for the guest o-xylene molecule decreases to half that in the Hofmann-daotn-type clathrate Cd[NH2(CH2)8NH2]Ni(CN)4·G.The Crystal structures of ,-Diaminoalkanecadmium(II)Tetracyanonickelate(II) - Aromatic Molecule Inclusion Compounds. VI.  相似文献   
146.
The effects of surface roughness, grain size and target thickness on the cathodic sputtering and emission intensities of spectral lines in the Grimm glow lamp have been investigated for samples of aluminium alloys. The intensities of the alloying elements changed with discharge time because the θ phase (Al2Cu) and β phase (Si) are sputtered selectively. The selective sputtering of the θ phase in an Al—8% Cu alloy can be decreased and the intensities can be made constant during discharge by polishing the target surface with coarse sand paper before discharge. When a fine-grained Al—4.9% Cu—7.2% Si alloy sample was used as a target, the intensities remained nearly constant during discharge. The sample preparation for obtaining fine-grained samples involves casting the melt in a metal mould. The thickness of disk samples influences not only the sample temperature but the current, sputtering and intensities. Special attention should be paid to the thickness for the determination of copper in aluminium alloys.  相似文献   
147.
148.
Arsenobetaine, arsenocholine, trimethylarsine oxide and tetramethylarsonium iodide, which are contained in marine fishery products, were examined for their potencies on cell growth inhibition, chromosomal aberration and sister chromatid exchange (SCE). Arseno- betaine, the major water-soluble organic arsenic compound in marine animals, exhibited very low cytotoxicity towards mammalian cells. This compound showed no cell growth inhibition at a concentration of 10 mg cm−3 and the cytotoxicity was lower than 1/14 000th of that of sodium arsenite and 1/1600th of that of sodium arsenate towards BALB/c 3T3 cells. The chromosomal aberrations caused by arsenobetaine at a concentration of 10 mg cm−3 consisted mainly of chromatid gaps and chromatid breaks, but in this concentration chromosomal breakage owing to its osmotic pressure is likely to be considerable. No SCE was observed at a concentration of 1 mg cm−3. Arsenocholine and trimethylarsine oxide also showed no cell growth inhibited at a concentration of 10 mg cm−3. However, tetramethylarsonium iodide inhibition the growth of BALB/c 3T3 at a concentration of 8 mg cm−3. These compounds exhibited a low ability to induce chromosomal aberrations at a concentration range of 2–10 mg cm−3 and no SCE was observed at a concentration of 1.0 mg cm−3. These results suggested that the major and minor organic arsenic compounds contained in marine fishery products are much less cytotoxic inorganic arsenic, methylarsonic acid and dimethylarsinic acid. © 1998 John Wiley & Sons, Ltd.  相似文献   
149.
Miscibility of polycarbonate (PC)/poly (arylate) (PAr) was studied by differential scanning calorimetry (DSC), phase contrast microscopy with digital image analysis (DIA) system, FT-IR spectroscopy, and cloud points for the PC/PAr/methylene chloride ternary systems. PC and PAr were immiscible over the whole composition range from the thermodynamical viewpoint. However, PC/PAr is homogenized by transesterification between PC and PAr at high temperatures. There is observed a competition between phase separation due to thermodynamical factor and phase dissolution due to transesterification. The pattern of the phase separation was spinodal decomposition type and the structure was successfully analysed by DIA.  相似文献   
150.
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