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1.
A series of previously unreported aldehydes has been prepared by the formylation reaction of dipyrrolo[1,2-a;2':,1'-c]pyrazines and their 5,6-dihydro analogs by DMF and phosphorus oxychloride.  相似文献   
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New examples of the ortho effect in bisphenol A derivatives including interaction of the hydrogen of the ortho-hydroxy group with the neighbouring aromatic ring have been observed. The characteristic ions [M ? PhOH]+middot; (m/z = 134) and [M ? CH3 ? PhOH]+ (m/z = 119) were shown to form through the hydrogen transfer from hydroxy and isopropyl groups, respectively. The spectra of cyclic derivatives having ortho-hydroxy functions show [M ? 43]+, [M ? C8H9O]+, m/z = 147, m/z = 135 and [M ? C9H10O]+ ions. The proposed mechanims of the corresponding transformations were supported by mass spectra of deuterated analogues, methyl and trimethyl silyl ethers.  相似文献   
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Procedures were developed for preparation of optically active dendrones and dendrimers with terminal 1,2-hydroxylimino, 1,2-hydroxylamino and oxazolidinyl groups containing ether bonds in the branches and ester bonds in the backbone of the macromolecule. The compounds described may serve as chiral ligands for asymmetric metallocomplex catclysis.  相似文献   
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The amidation and alkaline hydrolysis of diazirine-3,3-dicarboxylic acid esters, which proceed with retention of the diazirine ring, were studied. The higher stability of diazirine-3,3-dicarboxylic acid esters as compared with their spirocyclic analogs is explained by the conformational lability of the C=O groups. The UV and mass spectra of the diazirines are discussed.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 901–906, July, 1981.  相似文献   
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Conclusions N-chloro-N-alkoxy-N-tert-alkylamines react exclusively with CN and SCN and partially with Et and AcO to give nucleophilic substitution products at the nitrogen atom. These compounds react with AcO and water to give nitroso compounds, with EtS and Ph3 P to give azoxy compounds, and with AgF and AgNO3 to give products of more complex transformations.For communication 14, see ref. [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2320–2326, October, 1981.  相似文献   
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We have synthesized nitro derivatives of pyrrolo[1,2-a]pyrazines using a nitrating mixture and acetyl nitrate. We have obtained the products of oxidation of the side chain of 1,6-substituted pyrrolo[1,2-a]-pyrazines. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1579–1586, October, 2005.  相似文献   
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