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101.
A.J. Leusink G. An Koten J.W. Marsman J.G. Noltes 《Journal of organometallic chemistry》1973,55(2):419-425
Bis{2-[(dimethylamino)methyl]phenyl}silverlithium has been prepared and characterized. Molecular weight determinations, and 13C NMR and 1H NMR spectra reveal that the compound exists (in benzene) as a tetranuclear mixed metal cluster containing aryl groups bridging the silver and lithium atoms. Silver-proton, silver-carbon and lithium-carbon couplings have been observed in the NMR spectra of this compound. 相似文献
102.
The Cr-Cr singly-bonded dimers [{η5-RC5H4Cr(CO)3}2] (1, R=Me; 2, R=CO2Et) reacted with an equivalent of elemental selenium in THF at room temperature to give the linear Cr2Se complexes [{η5-RC5H4Cr(CO)2}2Se] (3, R=Me; 4, R=CO2Et), whereas the linear Cr2Se complex (5, R=MeCO) reacted with excess NaBH4, Ph3PCHPh or 2,4-dinitrophenylhydrazine under respective conditions to afford the linear Cr2Se derivatives [{η5-RC5H4Cr(CO)2}2Se] (6, R=MeCH(OH); 7, R=PhCHCMe; 8, R=2,4-(NO2)2C6H3NHNCMe). Similarly, while the butterfly Cr2Se2 complexes [{η5-RC5H4Cr(CO)2}2Se2] (9, R=Me; 10, R=CO2Et) could be produced either by reaction of dimers 1 and 2 with an excess amount of elemental selenium, or by reaction of the linear complexes 3 and 4 with an equivalent of elemental selenium, the butterfly Cr2Se2 derivatives [{η5-RC5H4Cr(CO)2}2Se2] (12, R=MeCH(OH); 13, R=PhCHCMe; 14, R=2,4-(NO2)2C6H3NHNCMe) were yielded by reaction of the butterfly Cr2Se2 complex (11, R=MeCO) with an excess quantity of NaBH4, Ph3PCHPh and 2,4-dinitrophenylhyazine. Both the linear complexes 3, 4, 6-8 and the butterfly complexes 9, 10, 12-14 are new, which have been fully characterized by elemental analysis, spectroscopy and X-ray crystallography. 相似文献
103.
Hee-Yoon LeeMihyun An 《Tetrahedron letters》2003,44(14):2775-2778
α,β-Unsaturated ketones and aldehydes were selectively reduced to the corresponding saturated carbonyl compounds by Co2(CO)8-H2O system. The current reducing system also offered a chemoselective reduction of less substituted unsaturated carbonyl groups. 相似文献
104.
The effects of hydrodynamic interactions on the friction tensors for two particles in solution are studied. The particles have linear dimensions on nanometer scales and are either simple spherical particles interacting with the solvent through repulsive Lennard-Jones forces or are composite cluster particles whose atomic components interact with the solvent through repulsive Lennard-Jones forces. The solvent dynamics is modeled at a mesoscopic level through multiparticle collisions that conserve mass, momentum, and energy. The dependence of the two-particle relative friction tensors on the interparticle separation indicates the importance of hydrodynamic interactions for these nanoparticles. 相似文献
105.
Zi-Shu Yang Yuhang Yao Adam C. Sedgwick Cuicui Li Ye Xia Yan Wang Lei Kang Hongmei Su Bing-Wu Wang Song Gao Jonathan L. Sessler Jun-Long Zhang 《Chemical science》2020,11(31):8204
We report here porphodilactol derivatives and their corresponding metal complexes. These systems show promise as “all-in-one” phototheranostics and are predicated on a design strategy that involves controlling the relationship between intersystem crossing (ISC) and photothermal conversion efficiency following photoexcitation. The requisite balance was achieved by tuning the aromaticity of these porphyrinoid derivatives and forming complexes with one of two lanthanide cations, namely Gd3+ and Lu3+. The net result led to a metalloporphodilactol system, Gd-trans-2, with seemingly optimal ISC efficiency, photothermal conversion efficiency and fluorescence properties, as well as good chemical stability. Encapsulation of Gd-trans-2 within mesoporous silica nanoparticles (MSN) allowed its evaluation for tumour diagnosis and therapy. It was found to be effective as an “all-in-one” phototheranostic that allowed for NIR fluorescence/photoacoustic dual-modal imaging while providing an excellent combined PTT/PDT therapeutic efficacy in vitro and in vivo in 4T1-tumour-bearing mice.We report here porphodilactol derivatives and their corresponding metal complexes as “all-in-one” phototheranostics by controlling the relationship between intersystem crossing (ISC) and photothermal conversion efficiency following photoexcitation. 相似文献
106.
Jun Zhou Jie Yang Li Qi Xuan Shen Dunru Zhu Yan Xu You Song 《Transition Metal Chemistry》2007,32(6):711-715
A novel dinuclear nickel(II) complex, [Ni2(MOBPT)2Cl2(H2O)2]Cl2 · 7H2O (MOBPT = 4-(p-methoxyphenyl) −3,5-bis(pyridine-2-yl)-1,2,4-triazole), has been synthesized and characterized by elemental analysis, IR and single crystal X-ray
diffraction methods. The crystal structure determination shows that the dinuclear Ni2N8 unit is almost planer in which each NiII ion is coordinated by four nitrogen atoms from MOBPT equatorially and a water molecule and a chloride ion axially in a distorted
octahedral geometry. Magnetic measurements reveal a relatively weak antiferromagnetic exchange in the complex. 相似文献
107.
G.B. Song C.Q. Han J.K. Liang Q.L. Liu F.S. Liu G.H. Rao 《Journal of solid state chemistry》2004,177(7):2394-2403
The subsolidus phase relations of the PrOx-CaO-CuO pseudo-ternary system sintered at 950-1000°C have been investigated by X-ray powder diffraction. In this system, there exist one compound Ca10Pr4Cu24O41, one Ca2Pr2Cu5O10-based solid solution, seven three-phase regions and two two-phase regions. The crystal structures of Ca10Pr4Cu24O41 and Ca2Pr2Cu5O10-based solid solution have been determined. Compound Ca10Pr4Cu24O41 crystallizes in an orthorhombic cell with space group D2h20−Cccm, Z=4. Its lattice parameters are a=11.278(2) Å, b=12.448(3) Å and c=27.486(8) Å. The crystal structure of Ca2Pr2Cu5O10-based solid solution is an incommensurate phase based on the orthorhombic NaCuO2 type subcell. The lattice parameters of the subcell of the Ca2.4Pr1.6Cu5O10 are a0=2.8246(7) Å, b0=6.3693(5) Å, c0=10.679(1) Å, and those of the orthorhombic superstructure are with a=5a0, b=b0, c=5c0. The Ca2.4Pr1.6Cu5O10 structure can also be determined by using a monoclinic supercell with space group C2h5−P21/c, Z=4, a=5a0, b=b0, and β=104.79(1)° or 136.60(1)°, V=5a0b0c0. 相似文献
108.
1-(p-Substituted phenyl)-2-vinylcyclopropanes such as 1-phenyl-2-vinylcyclopropane (Ia), 1-(p-chlorophenyl)-2-vinylcyclopropane (Ib), 1-(p-anisyl)-2-vinylcyclopropane (Ic), and 1-(p-tolyl)-2-vinylcyclopropane (Id) were prepared and polymerized radically, cationically and with Ziegler–Natta catalysts. Ia and Ib polymerized exclusively in 1,5-fashion with radical initiators. However, Ic and Id polymerized in 1,5-fashion only with Ziegler–Natta catalysts. All polymers were soluble in ordinary organic solvent and solution-cast films were clear and flexible, showing Tg values in the range of 39–71°C. Spectral data indicated that the double bonds of the polymer chains were in trans form in all cases. The difference between the polymerizabilities of different monomers are interpreted in terms of electronic properties of substituents. 相似文献
109.
LiLi Liu WanHong Ma WenJing Song ChunCheng Chen Jun Lin JinCai Zhao XinHua Qian ShiBo Zhang 《中国科学:化学(英文版)》2007,50(6):770-775
This study investigated the visible-light catalysis mediated by zeolite NaY on the oxidation of dyes with H2O2. The results demonstrated that zeolite NaY acts as a sink for the electron from the photo-excited dye in the heterogeneous catalysis. Furthermore, the electron can effectively activate H2O2 to produce ·OH radical that is a powerful oxidant for the oxidation of dye at room temperature. The effects of the framework topology, Si/Al ratio, and exchangeable cation of the zeolite on the oxidation of various dyes were also shown. 相似文献
110.
S. V. Volkov S. V. Kutyakov A. N. Levov E. I. Polyakova Le Tuan An S. A. Soldatova P. B. Terentiev A. T. Soldatenkov 《Chemistry of Heterocyclic Compounds》2007,43(10):1260-1268
It has been established that on heating, 3-benzoyl-4-hydroxy-1-methyl-4-phenylpiperidine is ring-opened in the presence of
arylamines by a type of retroaldol reaction, with subsequent transamination of the intermediate Mannich base and the formation
of 3-arylamino-1-oxo-1-phenylpropanes. When using arylhydrazines this γ-piperidol is recyclized with the formation of 1,3-diarylpyrazoles
and their 4,5-dihydro derivatives. The mass spectral behavior of a series of 3-arylamino-substituted 1-phenylpropanones has
been studied.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1486–1495, October, 2007. 相似文献