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121.
Pullin等人曾对全氟碘代烷与三级胺的相互作用进行了研究,发现R_(?)I与NR_3能形成电荷转移络合物,即:R_(?)…I…NR_3。但此后却未见到有关反应的报道。我们发现在钯催化剂存在下,全氟碘化物与三乙胺能发生反应,反应条件较为温和,产物为氟代烷基烯基二乙基胺1。反应可能是在三乙胺中先产生一个双键,然后β碳原子接上一个全氟烷基。1的IR和NMR与Blanc报道的一致。化合物1经水解可得胺基烯酮2。在酸溶液中水解时,速度明显加快,而在碱溶液中,不仅不能加快水解速度,而且还有副反应发生。我们对化合物2进 相似文献
122.
A new synthetic route for the preparation of the betain-like compound (CH3N)6P4F8 from (CH3NPF3)2,N-methyl-hexamethyldisilazane andN,N-dimethyl-urea has been found. The steps of this multi-stage reaction could be rationalized to a far extent.
10. Mitteilung:Kubjacek M., Utvary K., Mh. Chem.112, 305 (1981). 相似文献
123.
The stereochemistry of substituted cyclopent-2-en-1-ones was studied by NMR. The existence of non-planar rings is indicated and conformational analysis, based principally upon examination of the coupling constants enables the conformational population to be estimated; trans dihalogeno derivatives, for example, occur predominantly in the diaxial form. 相似文献
124.
Kihyun Cho Jangwon Oh Taewon Lee Dongwook Shin 《Journal of Analytical and Applied Pyrolysis》2007,80(2):502-506
Aerosol flame pyrolysis deposition method was applied to deposit the oxide glass electrolyte film and LiCoO2 cathode for thin film type Li-ion secondary battery. The thicknesses of as-deposited porous LiCoO2 and Li2O–B2O3–P2O5 electrolyte film were about 6 μm and 15 μm, respectively. The deposited LiCoO2 was sintered for 2 min at 700 °C to make partially densified cathode layer, and the deposited Li2O–P2O5–B2O3 glass film completely densified by the sintering at 700 °C for 1 h. After solid state sintering process the thicknesses were reduced to approximately 4 μm and 6 μm, respectively. The cathode and electrolyte layers were deposited by continuous deposition process and integrated into a layer by co-sintering. It was demonstrated that Aerosol flame deposition is one of the good candidates for the fabrication of thin film battery. 相似文献
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Abdallah Aissa Michel Gruselle René Thouvenot Rainer Traksmaa 《Journal of solid state chemistry》2007,180(8):2273-2278
The reaction between phenyl phosphonic dichloride (C6H5P(O)Cl2) and synthetic calcium hydroxy- and fluorapatite has been investigated. The presence of mono- or polymeric (C6H5PO) fragment bound to hydroxyapatite was evidenced by IR, and solid-state 31P NMR spectroscopy. X-ray powder analysis has shown that the apatitic structure remains unchanged during the reaction. In contrast, no reaction was found using fluorapatite. According to the results found for these two different apatites a mechanism was proposed for the formation of covalent P-O-P bonds as the result of a reaction between the C6H5P(O)Cl2 organic reagent and (HPO4)− and/or OH− ions of the hydroxyapatite. 相似文献
130.
Geometries and stabilization energies of various simple H-bonded complexes (water dimer, hydrogen fluoride dimer, formamide
dimer, formic acid dimer) have been determined by a gradient optimization that eliminates the basis set superposition error
(BSSE) by the counterpoise (CP) method in each gradient cycle as well as by the standard gradient optimization. Both optimization
methods lead to different potential energy surfaces (PES). The difference depends on the theoretical level used and is larger
if correlation energy is considered. Intermolecular distances from the CP-corrected PES are consistently longer, and this
difference might be significant (∼0.1 ?); also angular characteristics determined from both surfaces differ significantly.
Different geometries were obtained even when passing to larger basis sets (aug-cc-pVDZ). The standard optimization procedure
can result in a completely wrong structure. For example, the “quasi-linear” structure of the (HF)2 (global minimum) does not exist at the standard MP2/ 6-31G** PES (where only cyclic structure was detected) and is found
only at the CP-corrected PES. Stabilization energies obtained from the CP-corrected PES are always larger than these from
the standard PES where the BSSE is added only a posteriori for the final optimized structure; both energies converge only
when passing to a larger basis set (aug-cc-pVDZ).
Received: 11 March 1998 / Accepted: 19 June 1998 / Published online: 4 September 1998
RID="
ID=" <E6>Acknowledgements.</E6> The project was supported by the Grant Agency of the Czech Republic (Grant No. 203/98/1166).
RID="
ID=" <E5>Correspondence to</E5>: P. Hobza 相似文献