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以2,6-二氯吡啶为起始原料, 经肼基化、还原、硝化、Nietzki-Dietschy环合4步反应得到5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物。 结合反应机理讨论了还原、硝化、Nietzki-Dietschy环合反应的影响因素,获得了合成5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的最佳工艺条件,目标产物的总收率为59.2%。 用1H NMR、MS和IR谱对5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的结构进行了表征。 相似文献
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以2,6-二氯吡啶为起始原料,经肼基化、还原、硝化、Nietzki-Dietschy环合4步反应得到5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物.结合反应机理讨论了还原、硝化、Nietzki-Dietschy环合反应的影响因素,获得了合成-.氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的最佳工艺条件,目标产物的总收率为59.2%.用1H NMR、MS和IR谱对5-氨基-6-硝基-[1,2,5]噁二唑并[3,4-b]吡啶-1-氧化物的结构进行了表征. 相似文献
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3-氨基-4-氧代氰基呋咱捕获与表征 总被引:1,自引:0,他引:1
3,4-双(4-氨基呋咱-3-基)氧化呋咱由活性中间体3-氨基-4-氧代氰基呋咱分子间发生二聚获得,但3-氨基-4-氧代氰基呋咱不稳定,无法通过分离、纯化及光谱鉴定证实其存在.采用4种不同的烯烃与3-氨基-4-氧代氰基呋咱发生1,3-偶极环加成反应得到3-(4-氨基呋咱-3-基)-5-氰基-Δ2-异噁唑啉、3-(4-氨基呋咱-3-基)-5-乙酰氧基-Δ2-异噁唑啉、3-(4-氨基呋咱-3-基)-5-正丁基-Δ2-异噁唑啉及3-(4-氨基呋咱-3-基)-环己烷并-Δ2-异噁唑啉4种Δ2-异噁唑啉衍生物;采用苯甲酰氯为捕获剂,与3-氨基-4-氧代氰基呋咱反应获得了3-氨基-4-(N-苯甲酸基氨基羰基)呋咱化合物;通过红外光谱、核磁共振光谱、质谱、元素分析表征了5种新化合物的结构,提供了活性中间体3-氨基-4-氧代氰基呋咱存在的间接证据. 相似文献
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3,4-双取代氧化呋咱衍生物的合成、结构表征及热性能研究 总被引:1,自引:0,他引:1
以自制的偕氯肟基化合物为原料, 通过脱氯化氢、分子间二聚环化及硝化等反应合成了自行设计的8种目标化合物--3,4-二苯基氧化呋咱(1)、3,4-二(吡啶-2 -基)氧化呋咱(2)、3,4-二(吡啶-3 -基)氧化呋咱(3)、3,4-二(吡啶-4 -基)氧化呋咱(4)、3,4-二(吡嗪-2 -基)氧化呋咱(5)、3,4-二(4 -甲氧基苯-1 -基)氧化呋咱(6)、3,4-二(4 -氯苯-1 -基)氧化呋咱(7)及3,4-二(3 ,5 -二硝基苯-1 -基)氧化呋咱(8). 利用红外光谱、核磁共振、质谱、元素分析等手段对8种目标化合物进行了结构表征. 初步考察了不同取代基对二聚反应的影响, 发现取代基的吸电子能力越强, 越有利于形成氧化氰中间体结构, 目标产物收率越高|以化合物5为例, 探讨了反应温度、缚酸剂、缚酸剂浓度、反应介质等对二聚反应的影响, 确定适宜的反应条件为: 反应温度2~10 ℃, 缚酸剂选择3%~5%浓度的Na2CO3或KHCO3, 反应介质为低沸点溶剂, 在此反应条件下, 化合物的收率分别为64.7%, 71.3%, 70.0%, 71.1%, 75.6%, 58.1%, 59.4%, 42.7%|利用差示扫描量热法(DSC)研究了目标化合物的热稳定性, 其中苯基取代衍生物的热稳定性较氮杂环衍生物好. 相似文献
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以3,4-双(4’-硝基呋咱-3’-基)氧化呋咱为原料,设计并合成了新型双呋咱并[3,4-b∶3’,4’-f]氧化呋咱并[3″,4″-d]氧杂环庚三烯(1),收率50.1%,其结构经13C NMR,15N NMR,IR,MS和元素分析表征。最佳的反应条件为:以无水碳酸钠为催化剂,乙腈(含水量0.04%)为溶剂,于80℃反应3.5 h。用B3LYP方法在6-31G**基组水平上对1的结构进行了计算,得到了稳定的几何构型和键级。在振动分析的基础上求得体系在不同温度下的热力学性质,得到了温度对热力学性能影响的关系式。1的性能研究表明,1的m.p.92℃~94℃,爆速8 256m.s-1(1.85 g.cm-3),摩擦感度0%(90°摆角),撞击感度12%(10 kg,25 cm),特性落高H50=57.5 cm(5 kg)。 相似文献
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ZHOU Yan-shui WANG Bo-zhou WANG Xi-jie ZHOU Cheng NING Yan-li LIAN Peng LI Jian-kang ZHANG Ye-gao 《合成化学》2012,20(2)
以3,4-双(4′-硝基呋咱-3′-基)氧化呋咱为原料,设计并合成了新型双呋咱并[3,4-b∶3′,4′-f]氧化呋咱并[3″,4″-d]氧杂环庚三烯(1),收率50.1%,其结构经13C NMR,15N NMR,IR,MS和元素分析表征.最佳的反应条件为:以无水碳酸钠为催化剂,乙腈(含水量0.04%)为溶剂,于80℃反应3.5h.用B3LYP方法在6-31G**基组水平上对1的结构进行了计算,得到了稳定的几何构型和键级.在振动分析的基础上求得体系在不同温度下的热力学性质,得到了温度对热力学性能影响的关系式.1的性能研究表明,1的m.p.92℃~94℃,爆速8 256m·s-1(1.85 g·cm-3),摩擦感度0%(90°摆角),撞击感度12%(10 kg,25 cm),特性落高H50 =57.5 cm(5 kg). 相似文献
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利用L-脯氨酸催化的5-氯水杨醛(1)与6-甲基-4-羟基吡喃酮(2)的缩合反应及硫酸铜催化下与1,3-二甲基-5-氨基吡唑(3)的串联反应,合成得到了10-氯-1,3-二甲基-5-(2-氧代丙基)色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(4)和10-氯-5-二乙氧基甲基-1,3-二甲基色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(5).化合物5的结构通过单晶X射线衍射法确定:晶体属于三斜晶系,空间群P-1;相对分子质量Mr=803.68;晶胞参数a=1.03160(10)nm,b=1.42900(13)nm,c=1.44268(15)nm;V=1.9448(3)nm~3;Z=2;晶胞密度Dc=1.372g/cm~3;吸收系数μ=0.228mm-1;单胞中电子的数目F(000)=840.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R=0.0681,w R=0.2051.在晶体结构中色烯环与吡啶环及吡唑环近似于共平面. 相似文献
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Pawlas J Vedsø P Jakobsen P Huusfeldt PO Begtrup M 《The Journal of organic chemistry》2000,65(26):9001-9006
1-Hydroxypyrazolo[3,4-c]quinoline (22), 1-hydroxypyrazolo[4, 3-c]quinoline (21), 1-hydroxypyrazolo[3,4-c]isoquinoline (20), and 1-hydroxypyrazolo[4,3-c]isoquinoline (19) were prepared from 1-benzyloxypyrazole (6), establishing the pyridine B-ring in the terminal step. The pyridine ring of pyrazoloquinolines 14 and 18 was formed via cyclization of a formyl group at C-4 or C-5 and an amino group of a 2-aminophenyl substituent at C-5 or C-4 in 1-benzyloxypyrazole. The pyridine ring of pyrazoloisoquinolines 5 and 9 was created via cyclization of a formyl group in a 2-formylphenyl substituent at C-4 or C-5 with an iminophosphorane group installed at C-5 or C-4 of 1-benzyloxypyrazole by lithiation followed by reaction with tosyl azide and then with tributylphoshine utilizing the Staudinger/aza-Wittig protocol. The 2-aminophenyl and the 2-formylphenyl substituent were introduced at C-5 or C-4 by regioselective metalation followed by transmetalation to the pyrazolylzinc halide and subsequent palladium-catalyzed cross-coupling with 2-iodoaniline or 2-bromobenzaldehyde. The order of reactions and use of protecting groups in the individual sequences have been optimized. The 1-benzyloxy-substituted pyrazoloquinolines and isoquinolines thus obtained were debenzylated by strong acid to the corresponding 1-hydroxy-substituted pyrazoloquinolines and isoquinolines 19-22. 相似文献
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The reactions of heteropentalene mesomeric betaine 1 and nitrogen-rich mesoionic tetrazolium-5-amides 4, 11 and 16-18 with electron-deficient unsaturated compounds have been studied. Novel heterocyclic systems, tetrazolo[4,5-a][1,7]benzodiazonine inner salt 2 and 3-oxo-3,7-dihydro-2H-pyrazolo[3,4-b]pyridine 5, have been synthesized by the reactions of dimethyl acetylenedicarboxylate with 1 and tetrazolium-5-anilide 4, respectively, and fully characterized by X-ray crystallography. It has been found that the reactions of other tetrazolium-5-amides are also initiated by the nucleophilic addition of the electron-rich amide nitrogen to the electron-deficient unsaturated compounds. 相似文献
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Synthesis of linear and cyclic compounds containing the 3,4-bis(furazan-3-yl)furoxan fragment 总被引:1,自引:0,他引:1
A. I. Stepanov A. A. Astrat’ev D. V. Dashko N. P. Spiridonova S. F. Mel’nikova I. V. Tselinskii 《Russian Chemical Bulletin》2012,61(5):1024-1040
Some chemical transformations of 3,4-bis(4-aminofurazan-3-yl)furoxan (1) and 3,4-bis-(4-nitrofurazan-3-yl)furoxan (2) were considered. Compounds 1 and 2 are valuable synthons for the preparation of linear and cyclic compounds containing the 3,4-bis(furazan-3-yl)furoxan fragment. The reaction of compound 2 with a series of N- and O-nucleophiles afforded novel heterocyclic systems: 7-R-7H-difurazano[3,4-b:3′,4′-f]furoxano[3″,4″-d]azepine and difurazano[3,4-b:3′,4′-f]furoxano[3″,4″-d]oxepin. 相似文献
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V. G. Andrianov I. B. Starchenkov A. F. Mishnev 《Chemistry of Heterocyclic Compounds》1997,33(8):977-981
The corresponding 7-substituted furazano[3,4-b]tetrazolo[1,2-d]pyrazines were obtained by nucleophilic substitution of the azido group in 7-azidofurazano[3,4-b]tetrazolo[1,2-d]pyrazine. It was shown that these compounds exist in the tetrazole form in the crystalline state; in solutions, a tautomeric equilibrium is observed between the azide and tetrazole forms. Further reaction with nucleophiles leads to the production of 5,6-disubstituted furazano[3,4-b]pyrazines.For Communication 1, see [2].Latvian Institute of Organic Synthesis. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1120–1124, August, 1997. 相似文献
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3-Diazopyrazolo[3,4-b] pyridine was synthesized and its transformations were investigated. With reactive methylene compounds the corresponding hydrazones are formed and they can be cyclized into condensed 1,2,4-triazine derivatives. With amines of thiols the diazo compound forms triazenes or diazosulfides. From hydrazines tetrazenes are formed first and they give upon fragmentation a mixture of N-N or C-N bond fission products. The diazo compound undergoes cycloaddition, reacting as a 1,2-dipole. 3-Azidopyrazolo [3,4-b] pyridine was prepared and converted into the tetrazolo isomer, whereas the 3-amino compound was used for the synthesis of some pyridopyrazolopyrimidines. 相似文献
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Reaction of β-aminocrotonamide ( 1 ) with succinic anhydride gave β-succinaminocrotonamide ( 3a ), which was treated with base to cyclize to 3,4-dihydro-6-methyl-4-oxo-2-pyrimidinepropanoic acid ( 4a ). Similarly, pyrimidinepentanoic acid derivative 4b was prepared from compound 1 and glutaric anhydride. Reaction of compound 1 with glutarate, adipate, and phthalate gave the corresponding pyrimidines 4b, 4c and 4d , while reaction of compound 1 with malonate gave 2-hydroxypyridine derivative 11 and dimethylpyrimidinone 4e . Reaction of dimethyl fumarate with compound 1 in the presence of methoxide gave a poor yield of pyrrolo[3,4-c]pyridine derivative 13 . 相似文献
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5-Cyano-3,4-dihydro-6-phenyl-2-substitutedpyrimidin-4-ones 1a-c reacted with phosphorus oxychloride to give the corresponding 4-chloropyrimidine derivatives IIa-c . Compounds IIa-c reacted with aniline and hydrazine to yield the 4-anilino, IIIa,e , and 4-hydrazino, IIIb-d derivatives. The 4-hydrazino analogues IIIb,c could be converted into the triazolo[4,3-c] and tetrazolo[4,5-c]pyrimidines IV and V by the action of carbon disulphide and nitrous acid, respectively. The reaction of IIb,c with phenylhydrazine afforded directly the 5-amino-4,6-diphenyl-6H-2-substitutedpyrazolo[3,4-d]pyrimidines VIa,b . The 4-chloro derivative IIa reacted with antrhanilic acid to form the 5-cyano-2,4-diphenyl-6-(o-carboxyphenylamino)pyrimidine VIII , which could be cyclised into the 4-cyano-1,3-diphenyl-10H-pyrimido[6,1-b]quinazolin-10-one IX by heating with acetic anhydride. 相似文献
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Joze Kobe D. E. O'Brien R. K. Robins Thomas Novinson 《Journal of heterocyclic chemistry》1974,11(6):991-996
The reaction of 4-hydrazino-7-phenylpyrazolo[1,5-a]-1,3,5-triazine ( 4 ) with nitrous acid gave 8-phenyltetrazolo[1,5-e]pyrazolo[1,5-a]-1,3,5-triazine ( 5b ), which was determined by pmr and ir spectra to be in equilibrium with 4-azido-7-phenylpyrazolo[1,5-a]-1,3,5-triazine ( 5a ). The equilibrium between the tetrazolo ( 5b ) and azido ( 5a ) forms was studied by pmr and an attempt was made to determine if substituents in the pyrazole nucleus could sufficiently stabilize the tricyclic tetrazolo form ( 5b ) over the bicyclic azido form ( 5a ). Thermal degradation of 5 (a ? b) in an aprotic solvent gave 4-amino-7-phenylpyrazolo[1,5-a]-1,3,5-triazine ( 7 ), indicating the probability of a nitrene mechanism involved in the decomposition. Heating 5 in aqueous base gave both 7 and the “hydroxy” analog, 7-phenylpyrazolo[1,5-a]-1,3,5-triazin-4(3H)one ( 6 ), further substantiating the existence of a nitrene intermediate with a competing nucleophilic displacement of the azido group by a hydroxyl group. Cyclization of 4 with diethoxymethylacetate (DEMA) gave 8-phenyl-s-triazolo[4,3-e]pyrazolo[1,5-a]-1,3,5-triazine ( 8 ), which underwent thermal rearrangement to 8-phenyl-s-triazolo[2,3-e]pyrazolo[1,5-a]-1,3,5-triazine ( 9 ). Acid catalyzed ring opening of 9 with formic acid gave 3-N-formamido-5-phenyl-2(2-s-triazolyl)pyrazole ( 10 ). The failure of 10 to recyclize to 9 with the resultant loss of water, supported the theory that the rearrangement of 8 to 9 might occur simply as a concerted, thermally induced “anhydrous” rearrangement rather than via a covalently hydrated intermediate or a Dimroth type mechanism (in the base catalyzed rearrangement). 相似文献
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L. V. Grishchuk E. I. Ivanov V. E. Kuz'min A. M. Turyanskaya R. Yu. Ivanova 《Chemistry of Heterocyclic Compounds》2003,39(3):340-343
The reaction of 4-aryl-2-hydrazino-3-nitro-6-R-quinolines with NaNO2 in AcOH gives the corresponding tetrazolo[1,5-a]quinolines. In contrast to tetrazolo[1,5-c]pyrimidines they cannot be converted to 6-R-4-phenyl[1,2,5]oxadiazolo[3,4-b]quinoline-3-oxides by heating in THF, toluene, or AcOH. Total energy quantum-chemical calculations using the MINDO/3 and MNDO methods show that [1,2,5]oxadiazolo[3,4-b]quinoline-3-oxides are significantly higher in energy (230-280 kcal/mol) than the mentioned tetrazolo[1,5-a]quinolines and hence their formation is unlikely. 相似文献
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Several tetrazolo[1,5-a]pyridines/2-azidopyridines undergo photochemical nitrogen elimination and ring expansion to 1,3-diazacyclohepta-1,2,4,6-tetraenes, as well as ring cleavage to cyanovinylketenimines, in low temperature Ar matrices. 6,8-Dichlorotetrazolo[1,5-a]pyridine/2-azido-3,5-dichloropridine undergoes ready exchange of the chlorine in position 8 (3) with ROH/RONa. 8-Chloro-6-trifluoromethyltetrazolo[1,5-a]pyridine undergoes solvolysis of the CF(3) group to afford 8-chloro-6-methoxycarbonyltetrazolo[1,5-a]pyridine. Several tetrazolopyridines/2-azidopyridines afford 1H- or 5H-1,3-diazepines in good yields on photolysis in the presence of alcohols or amines. 5-Chlorotetrazolo[1,5-a]pyridines/2-azido-6-chloropyridines and undergo a rearrangement to 1H- and 3H-3-cyanopyrroles and, respectively. The mechanism of this rearrangement was investigated by (15)N-labelling and takes place via transient 1,3-diazepines. The structures of 6,8-dichloro-tetrazolo[1,5-a]pyridine, 6-chloro-8-ethoxytetrazolo[1,5-a]pyridine, dipyrrolylmethane, and 2-isopropoxy-4-dimethylamino-5H-1,3-diazepine were determined by X-ray crystallography. In the latter case, this represents the first reported X-ray crystal structure of a 5H-1,3-diazepine. 相似文献