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1.
《中国化学快报》2020,31(6):1576-1579
Reported herein is the first example of electrochemical selenocyanation of imidazo[1,5-a]quinolines with KSeCN under metal catalyst-and chemical oxidant-free conditions.This sustainable strategy shows a broad scope and great compatibility with functional groups,and affords synthetically and biologically important selenocyanated imidazo[1,5-a]quinolines in good to excellent yields with cheap graphite and Ni plates as the electrodes.The gram-scale synthesis was also successfully conducted,which might demonstrate the potential value of this electrochemical protocol. 相似文献
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《中国化学快报》2020,31(7):1855-1858
By virtue of electrochemistry, a series of α,α-dihaloacetophenones were easily obtained with good to excellent yields. This electrochemical procedure was taken in a divided cell with constant current in aqueous media. The reaction can be carried out smoothly at room temperature under metal and oxidant free condition, which provides an eco-friendly synthesis for the α,α-dihaloacetophenone derivatives. 相似文献
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ZONG Guang-Ning LI Feng-Yun FAN Zhi-Jin MAO Wu-Tao SONG Hai-Bin CHEN Lai ZHU Yu-Jie 《结构化学》2015,34(6)
The title compound diethyl 2-(3,4-dichloroisothiazol-5-yl)-4-(trifluoromethyl)-4,5-dihydrothiazol-4-yl-3-methylbenzoate(C15H9Cl2F3N2O2S2, Mr = 441.26) was prepared from methyl 3,4-dichloroisothiazole-5-carboxylate as the starting material by four steps of reaction. Its structure was characterized by IR, 1H-NMR, 13C-NMR, EA and single-crystal X-ray diffraction. The crystal of the title compound belongs to the monoclinic system, space group P21/c with a = 8.8437(18), b = 16.128(3), c = 12.305(3), β = 91.68(3)o, V = 1754.4(6) 3, Z = 4, Dc = 1.671 g/cm3, μ(Mo Ka) = 0.71073 mm-1, F(000) = 888, R = 0.0384 and w R = 0.0778. Weak π-π interactions occur between the isothiazole rings and phenyl rings of adjacent molecules to form a one-dimensional chain and stabilize the crystal structure. Bioassay indicates that the title compound has good activity against the fungi and TMV tested. 相似文献
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In this paper, we consider strong/classical solutions to the 3D compressible Hall-magnetohydrodynamic system. First, we prove the existence of local strong solutions with positive density. Then the existence of global small solutions with small initial data is proved. Optimal time decay rate is also established. 相似文献
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《结构化学》2020,39(9):1689-1693
Hydrothermal reaction of Cu(NO_3)_2·3 H_2O and 4-(4-carboxyphenoxy)isophthalic acid(H_3cpia) results in a two-dimensional coordination polymer based on paddle-wheel-like dinuclear clusters, namely [C_(60)H_(54)Cu_4O_(39)]_n(1). Complex 1 is of triclinic system, space group P1 with a = 10.7318(18), b = 12.267(2), c = 14.528(2) ?, α = 113.560(2)o, β = 96.156(3)o, γ = 103.552(3)o, V = 1660.5(5) ?~3, Z = 1, S = 1.057, F(000) = 842, R = 0.0517 and wR = 0.1426(I 2σ(I)). In this structure, tricarboxylate liagnds are partial deprotonation and potenial proton carriers. Strong antiferromagnetic interaction between Cu~(Ⅱ) ions exists within the Cu_2 cluster and complex 1 exhibits relatively high proton conductivity(σ 1.23 × 10~(-5) S×cm~(-1)) at 76% relative humidity(RH). 相似文献
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设X是维数大于2的Banach空间,映射δ:B(X)→B(X)是2-局部Lie三重导子,则对所有A∈B(X)有δ(A)=[A,T]+φ(A),这里T∈B(X),φ是从B(X)到FI的齐次映射且满足对所有A,B∈B(X)有φ(A+B)=φ(A),其中B是交换子的和. 相似文献
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《Tetrahedron letters》2019,60(24):1620-1623
5-Aryloxazolidines react with active methylene compounds in the presence of catalytic magnesium ethoxide to give methylene-linked 1,3-dicarbonyl compounds, while the similar reaction with 2-oxindoles results in 3-methyl derivatives. 相似文献