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61.
An effective route to spiro[indoline-3,4′-pyridine]-3′-carboxylate derivatives is described. This involves reaction of isatin, 1-phenyl-2-(1,1,1-triphenyl-λ5-phosphanylidene)-1-ethanone, and benzylamine derivatives or aliphatic amines in the presence of alkyl acetoacetate (1,3-dicarbonyl compounds) in dry methanol under reflux conditions. The reactive 1:1 enaminone, which is obtained from the addition of the amine to 1,3-dicarbonyl compound, adds to the α,β-unsaturated ketone, which is formed from the reaction of isatin and 1-phenyl-2-(1,1,1-triphenyl-λ5-phosphanylidene)-1-ethanone, to produce the alkyl 1′-benzyl-2′-methyl-2-oxo-6′-phenyl-1′H-spiro[indoline-3,4′-pyridine]-3′-carboxylate derivatives in excellent yields. 相似文献
62.
Technical properties of two naphthalimide based disperse dyes on nylon 6 and polyester fibers were investigated in the presence of urea.The two naphthalimide based disperse dyes were synthesized.The dyes were purified and then fully characterized using ~1H-NMR,FTIR and melting point analysis.Dispersion of the dyes was prepared in water and applied on nylon 6 and PET fibers.The dyes offered good build-up properties on the substrates.In order to increase dye adsorption of the substrates,urea was added into... 相似文献
63.
Seyyed Javad Sabounchei Sadegh SalehzadehMarjan Hosseinzadeh Fateme Akhlaghi BagherjeriHamid Reza Khavasi 《Polyhedron》2011,30(15):2486-2492
The reaction of the new ambidentate ylide, Ph3PCHCOCH2COOC2H5 (EAPPY), with HgX2 (X = Cl, Br and I) in equimolar ratios using methanol as the solvent leads to binuclear complexes of the type [EAPPY·HgX2]2 (X = Cl (1), Br (2) and I (3)). Single crystal X-ray analysis reveals the presence of a centrosymmetric dimeric structure containing the ylide and HgX2 (X = Br or I). The IR and NMR data of the product [(EAPPY)·HgCl2]2 (1), formed by the reaction of mercury(II) chloride with the same ylide, are similar to those of 2 and 3. Analytical data indicate a 1:1 stoichiometry between the ylide and Hg(II) halide in each of the three products. Theoretical studies indicate that the nature of the R group in ylides of the type Ph3PCHCOR has a weak effect on the Hg-C(ylide) bond length in binuclear Hg2L2I4 complexes. 相似文献
64.
Considering the thermodynamic aspects and reaction pathways of chemical adsorption of NH3 molecule at the open ends of boron nitride nanotubes (BNNTs), theoretically, it was found that the open-ended BNNTs are able
to cleave the N–H bond of NH3 via a one- or two-stepwise mechanism. The N-enriched and B-enriched open-ended BNNTs show a nucleophilic and electrophilic
behavior toward the NH3, respectively. Besides, some effects of this chemical adsorption on the electronic properties of BNNTs were explored. 相似文献
65.
For a locally compact semigroup \({\mathcal{S}}\), let \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))\) be the Banach space of all μ-measurable (\(\mu\in M_{a}({\mathcal{S}})\)) functions vanishing at infinity, where \(M_{a}({\mathcal{S}})\) denotes the algebra of all measures in the measure algebra \(M({\mathcal{S}})\) of \({\mathcal{S}}\) with continuous translations. Here, we study right compact multipliers on the Banach algebra \(L_{0}^{\infty}({\mathcal{S}},M_{a}({\mathcal{S}}))^{*}\) equipped with an Arens product. 相似文献
66.
Let T be a Wakamatsu tilting module. A module M is called (n, T)-copure injective (resp. (n, T)-copure flat) if ɛ
T
1 (N, M) = 0 (resp. Γ1
T
(N, M) = 0) for any module N with T-injective dimension at most n (see Definition 2.2). In this paper, it is shown that M is (n, T)-copure injective if and only if M is the kernel of an I
n
(T)-precover f: A → B with A ∈ Prod T. Also, some results on Prod T-syzygies are presented. For instance, it is shown that every nth Prod T-syzygy of every module, generated by T, is (n, T)-copure injective. 相似文献
67.
Dialkyl 2‐(alkylamino)‐4,9‐dihydro‐9‐oxocyclohepta[b]pyran‐3,4‐dicarboxylates are prepared in a one‐pot three‐component reaction of alkyl isocyanide, dialkyl acetylenedicarboxylate, and α‐tropolone (=2‐hydroxycyclohepta‐2,4,6‐trienone). The reaction proceeds smoothly at room temperature and under neutral conditions to afford tropolone derivatives in high yield. 相似文献
68.
69.
Nonlinear vibration mitigation of a flexible rotor shaft carrying a longitudinally dispositioned unbalanced rigid disc 总被引:1,自引:0,他引:1
Nonlinear Dynamics - This study is dedicated to investigate the nonlinear dynamics of a system composed of a flexible rotor shaft carrying a longitudinally dispositioned unbalanced rigid disc. The... 相似文献
70.
J. Safaei-Ghomi A. H. Bamoniri M. Soltanian-Telkabadi 《Chemistry of Heterocyclic Compounds》2006,42(7):892-896
Ten new N-phenylpyrazoline derivatives have been synthesized in high yields by condensation of chalcones with phenylhydrazine
in the presence of potassium carbonate in reflux conditions. The workup is simple and involves treatment with ice-cold water.
As compared with the previous method a considerable increase in the reaction rate with better yields has been observed.
Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1032–1036, July, 2006. 相似文献