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1.
我们用CNDO/Ⅱ方法UI对四甲基乙烯,偏甲基乙氧基乙烯,三甲基乙烯和丙烯睛等四个烯烃分子作了量子化学计算,它们的几何参数均采用pople标准数据。 相似文献
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The photocycloaddition of 8-methoxypsoralen to cyclothexene and to heptene-1 was found to give 3,4-dihydrobicyclo (4,2,0) octano (7",8":3,4) 8-methoxypsoralen (4) and a mixture of 3, 4-dihydro-(1-n-pentyl) cyclobutano-(2", 3":3,4) 8-methoxypsoralen (5) and the isomer 6 respectively. Stern-Volmer plot and quenching studies indicate that the reaction proceeds via psoralen triplet excited state. 相似文献
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在溴和8-甲氧基呋喃并[3′,2′∶6,7]香豆素(1,8-MOP)及NBS与1的反应中发现,溴首先在C_5取代,其次加到C_(4′,5′)双键上,最后加到C_(3,4)双键上,得到新化合物3,4,5,4′,5′-五溴-3,4,4′,5′-四氢-8-MOP(4).比较了1和香豆素对NBS反应的活性,发现NBS对香豆素不发生加成反应.这是由于1中的甲氧基和呋哺环使其对亲电试剂的反应活性比香豆素高,并由~(13)C核磁共振谱的C_3化学位移及这两个化合物中各双键的可极化率得到证实.4与二乙胺和吡啶的消除反应分别得到新化合物5和6. 相似文献
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我们曾研究了8-甲氧基呋喃并[3′,2′∶6,7]香豆素(8-MOP)与环己烯的光环合加成反应.本文进一步研究了8-MOP与2,3-二氢-γ-吡喃的光环合加成反应,并将上述两个反应的产物分离、鉴定,研究了其立体化学. 相似文献
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I. D. Bystryakova N. M. Smirnova T. S. Safonova 《Chemistry of Heterocyclic Compounds》1993,29(6):687-690
The reaction of 1,3-dimethyl-5-chloro-6-nitropyrido[2,3-d]pyrimidine-2,4-dione with CH-acids yielded 5-substituted pyridol[2,3-d]pyrimidines which were used in the synthesis of pyrrolo(2,34,5)pyrido[2,3-d]pyrimidines.For Communication 7, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 800–803, June, 1993. 相似文献
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《Tetrahedron letters》1988,29(51):6681-6684
The title compound (4) was synthesized by two sequential Friedlaender condensations between pentacyclic bis(ketoester) 2 and o-aminobenzaldehyde. The dihedral angle between the two quinoline rings in 4 is 76.4°; the nonbonded NXXXN interatomic distance in 4 is 4.32 Å. 相似文献
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M. A. Kukaniev S. Sh. Shukurov U. Norov Yu. Khodzhiboev 《Russian Chemical Bulletin》1999,48(2):364-366
2-R-5-Imino-6H-1,3,4-thiadiazolo[3,2-a]pyrimidin-7-ones react with aromatic and heterocyclic aldehydes in the presence of Et3N to give condensation products on the methylene group, which react with carbon disulfide to yield the corresponding 2,6-disubstituted
8-thioxo-9,9a-dihydro-1,3,4-thiadiazolo[3′,2′∶1,2]pyrimidino[5,6-d]1,3-thiazin-5-ones.
Deceased.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 366–368, February, 1999. 相似文献
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Timokhina L. V. Sokol’nikova O. V. Kanitskaya L. V. Voronkov M. G. 《Russian Journal of Organic Chemistry》2009,45(3):466-467
Russian Journal of Organic Chemistry - 相似文献
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以1,4-萘醌为原料,合成了含硫的醌构稠杂环化合物苯并[b]萘并[2′,3′∶5,6][1,4]二噻英并[2,3-i]噻蒽-5,7,9,14,16,18-六酮(4),其结构经1HNMR和IR确证。采用波长为800nm,脉宽为80fs的Ti∶Sapphire飞秒激光,运用双光束简并四波混频法测定了4的三阶非线性光学性能,结果表明,4的三阶非线性光学极化率χ(3),非线性折射率n2,分子二阶超极化率γ和响应时间分别为2.89×10-13esu,5.31×10-12esu,3.14×10-31esu和101fs。并分析了4的分子结构对其三阶非线性光学性能的影响。 相似文献
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Russian Journal of Organic Chemistry - 6′,7′-Dimethoxy-N-methyl-2′,3′-dihydro-1′H-spiro[cyclopentane-1,4′-isoquinoline]-1′-carboxamide reacted with... 相似文献
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A. Sh. Oganisyan A. S. Noravyan M. Zh. Grigoryan Arzh Sh. Oganisyan 《Chemistry of Heterocyclic Compounds》1999,35(9):1094-1096
New derivatives of pyrano[3,45,6]pyrido[2,3-d]pyrimidines were synthesized from ethyl 2-amino-7,7-dimethyl-7,8-dihydro-5H-pyrano[4,3-b]pyridine-3-carboxylate.A. L. Mndzhoyan Institute of Fine Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Erevan. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1239–1241, September, 1999. 相似文献
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The reaction of 8-hydroxy-1,3-dimethyl-4H-cyclohepta[c]furan-4-one with the ethoxymethylene derivatives of malononitrile or
ethyl cyanoacetate in the presence of KOH gave noncyclic cyanovinyl derivatives as their potassium salts rather than the expected
α-pyrone derivatives. They are smoothly cyclized to the target α-pyrones by refluxing with acid. The corresponding 3-benzamido-2H-pyran-2-ones
can be obtained in a single vessel from the 2-aryl-4-ethoxymethylene-4H-1,3-oxazol-5-ones using the same scheme.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1632–1638, November, 2008. 相似文献
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L. G. Levkovskaya I. E. Mamaeva L. A. Serochkina T. S. Safonova 《Chemistry of Heterocyclic Compounds》1993,29(4):480-483
Representatives of new heterocyclic systems were obtained — pyrido[3,25,6][1,4]thiazino[3,4-c]- and pyrimido[5,45,6][1,4]thiazino[3,4-c][1,2, 4]triazines. Hydrazides of N-(pyrid-3-yl)- and N-(pyrimid-5-yl)oxamic acids were isolated and characterized. Their acylation products were investigated.For communication 45, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 559–562, April, 1993. 相似文献
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本文阐明了1,3-环己二烯(1,3-CHD)与二苯并[a,j]蒽(DBA[a,j])在溶液中进行光环化加成反应时的光化学行为,并应用反应部位节点结构相关原理,提出了该反应是按对称性允许的协同过程进行的机理。我们首次观察到n4s+n4s光加成产物可以重排成n4s+n2s的光加成产物,在这个重排过程中,三线态双自由基是一个可能的中间体。 相似文献
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A. Sh. Oganisyan A. S. Noravyan G. M. Avetisyan 《Chemistry of Heterocyclic Compounds》1998,34(6):700-701
Methods for the synthesis of 2,4-dithioxo-6,6-dimethyl-5,6-dihydro-8H-pyrano(thiopyrano)[4,34,5]thieno[2,3-d]pyrimidines have been developed.For Communication 10 see [1].A. L. Mndzhoyan Institute of Technical Organic Chemistry, National Academy of Sciences of the Republic of Armenia, Erevan 375014. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 803–804, June, 1998. 相似文献