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41.
Dihydropyrimidines (DHPM) with a fused tetrazole ring have been synthesized via a smooth and efficient three-step protocol involving N,S-dimethylated and 2-hydrazinyl-dihydropyrimidine intermediates, respectively. The described protocol is applicable to electron rich and electron poor DHPM precursors as well. The insertion of tetrazole ring in monastrol type dihydropyrimidines makes it interesting for pharmacological investigations. 相似文献
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An efficient one-pot, convenient catalysis for the synthesis of 5-substituted-1H-tetrazoles is reported. The [3+2] cycloaddition involves various nitriles, sodium azide in refluxing DMF and AgNO3 as catalyst to give corresponding 5-substituted-1H-tetrazoles in good to excellent yields. It is expected that the reaction proceeds via in situ formation of a silver azide species, which participates in coordination of nitrile moiety followed by cycloaddition of azide ion to give tetrazole. 相似文献
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The [2+3] cycloaddition between various nitriles and sodium azide proceeds smoothly in the presence of zeolite and sulfated zirconia as effective catalysts, in water and DMF/MeOH, to give the corresponding 5-substituted 1H-tetrazoles in good to high yields. The reaction most probably proceeds through the in situ formation of catalyst azide species, followed by a successive [2+3] cycloaddition with the nitriles. This method has the advantages of high yields, simple methodology and easy work-up. The catalyst can be recovered by simple filtration and reused with good yields. 相似文献
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M. Pagacz-KostrzewaJ. Krupa A. Olbert-MajkutM. Podruczna R. BroniszM. Wierzejewska 《Tetrahedron》2011,67(44):8572-8582
The most stable conformers of 2-(tetrazol-1-yl)-, 3-(tetrazol-1-yl)- and 2-(tetrazol-5-yl)pyridines undergo photolysis in Ar matrices at cryogenic temperatures to yield pyridin-2-ylcarbodiimide or pyridin-3-ylcarbodiimide. Spectroscopic evidence of carbon-to-nitrogen rearrangement in the case of the 2-(tetrazol-5-yl)pyridine molecule is provided. For the latter molecule a second pathway leads to the 1-cyclopenta-2,4-dienylketenimine formation. The experimental findings are supported by extensive B3LYP/6-311++G(2d,2p) calculations. 相似文献
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Anastasiya P. Mosalkova Dr. Sergei V. Voitekhovich Alexander S. Lyakhov Ludmila S. Ivashkevich Pavel N. Gaponik Oleg A. Ivashkevich 《无机化学与普通化学杂志》2012,638(1):103-110
Three novel 5‐R‐tetrazolato complexes (R = Me, Ph, 4‐Py), namely [Zn2(MeCN4)4(DMSO)2] ( 1 ), [Cu2(PhCN4)4(en)2] · 2DMSO ( 2 ), and [Cu(4‐PyCN4)2(DMSO)2] · 4DMSO ( 3 ), were isolated as unexpected products under attempts to prepare heterometallic tetrazolates using a direct synthesis strategy in the Cu0‐ZnO‐en‐RCN4H‐DMSO system (en = ethylenediamine). The prepared compounds were characterized by elemental, single‐crystal X‐ray, and thermal analyses, and IR spectroscopy. Variation of the 5‐substituent of the tetrazole ring causes different composition of complexes 1 – 3 and diverse coordination modes of 5‐R‐tetrazolato ligands. Complex 1 is a 3D coordination polymer due to N1, N4‐bridging of 5‐methyltetrazolato anions. Complex 2 , with en as a coligand, has a dinuclear structure with two copper atoms linked together by two 5‐phenyltetrazolato ligands by tetrazole N2, N3 bridges. Complex 3 represents a 2D coordination polymer, formed due to 5‐(4‐pyridyl)tetrazolato bridges between adjacent copper atoms (with the tetrazole and pyridine rings nitrogen atoms as coordination centers). DMSO molecules, included in all the compounds, are solvate and/or coordinated ones. 相似文献
47.
《Journal of Coordination Chemistry》2012,65(17):3101-3107
The synthesis, crystal structures, and luminescent properties of two new complexes containing tetrazolyl ligands are described. Refluxing a mixture of fipronil (fipronil = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-carbonitrile), sodium azide, and CuCl2 in ethanol and water gives complex 1, [M(L)2](H2O)2] ? 2H2O (HL = (±)-5-amino-1-[2,6-dichloro-4-(trifluoromethyl)phenyl]-4-[(trifluoromethyl)sulfinyl]-1H-pyrazole-3-tetrazole, M = Cu). Hydrothermal reaction of fipronil, sodium azide, and Cd(ClO4)2 in the presence of water and ethanol (Demko–Sharpless tetrazole synthesis) yields 2, [M(L)2](H2O)2] ? 2H2O (M = Cd). The metals in both complexes are six coordinate from two water molecules, two nitrogens from different tetrazolyl groups, and two nitrogens from pyrazolyl groups. Photoluminescence studies reveal that 2 exhibits strong blue fluorescent emission at λ max = 451 nm in solid state at room temperature. 相似文献
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Synergistic Catalytic Effect of a Series of Energetic Coordination Compounds based on Tetrazole‐1‐acetic Acid on Thermal Decomposition of HMX 下载免费PDF全文
A series of energetic coordination compounds [Co(tza)2}n ( 1 ), [Bi(tza)3]n ( 2 ), {[Cu4(tza)6(OH)2] · 4H2O}n ( 3 ), [Mn(tza)2]n ( 4 ), {[Bi(tza)(C2O4)(H2O)] · H2O}n ( 5 ) and [Fe3O(tza)6(H2O)3]NO3 ( 6 ) based on tetrazole‐1‐acetic acid (Htza) were synthesized though environmentally friendly methods. The coordination compounds were characterized by elemental analyses, IR spectroscopy, single‐crystal and powder X‐ray diffraction (PXRD), thermogravimetric analyses (TG), and differential scanning calorimetry (DSC). Their catalytic performances and the synergetic catalytic effects between 1 and 2 , 3 and 4 , 5 and 6 on the thermal decomposition of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX) were all investigated by DSC. The results revealed that compounds 1 – 6 are thermally stable energetic compounds and they all exhibit high catalytic action for HMX thermal decomposition. The catalytic effects of the compounds on HMX thermal decomposition are closely related to the oxides, which come from the decomposition of the compounds, but have no positive relationships with the heat releases of the compounds themselves. Moreover, the synergetic catalytic effects between 1 and 2 , 3 and 4 , 5 and 6 were observed. Their mixtures at different mass ratio have different synergetic catalytic effects, and the sequence of the biggest synergetic index (SI) in each system is copper‐manganese system (compounds 3 and 4 ) > iron‐bismuth system (compounds 5 and 6 ) > cobalt‐bismuth system (compounds 1 and 2 ), indicating that the synergistic catalytic effects are mainly related to the combination and the proportion of the compounds. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(13):3629-3632
This study presents the synthesis and characterization of the oxidation products of 3,6‐diazido‐1,2,4,5‐tetrazine ( 1 ) and 6‐amino‐[1,5‐b ]tetrazolo‐1,2,4,5‐tetrazine ( 2 ). 3,6‐Diazido‐1,2,4,5‐tetrazine‐1,4‐dioxide was produced from oxidation with peroxytrifluoroacetic acid, and more effectively using hypofluorous acid, and 2 can be oxidized to two different products, 6‐amino‐[1,5‐b]tetrazolo‐1,2,4,5‐tetrazine mono‐N‐oxide and di‐N‐oxide. These N‐oxide compounds display promising performance properties as energetic materials. 相似文献