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1.
A facile and operationally simple route to diastereomerically pure, natural-like 3-azabicyclo[3.3.1]non-6-enes via microwave-assisted, BF3·OEt2-promoted aza-Prins reaction has been developed. Complexity-generating transformations based on these products involving reactive functionalities introduced during the aza-Prins step have been developed. 相似文献
2.
Yu. M. Atroshchenko N. K. Melekhina I. V. Shakhkel’dyan I. E. Yakunina A. N. Shchukin E. V. Shuvalova V. A. Subbotin 《Russian Journal of Organic Chemistry》2006,42(8):1220-1224
The electrophilic chlorine addition to 3-substituted 1,5-dinitro-3-azabicyclo[3.3.1]-non-6-enes in the tetrachloromethane is accompanied at an intramolecular 3,7-cyclization giving 6-chloro-3-R-1,5-dinitro-3-azoniatricyclo[3.3.1.03,7]nonane chlorides. The reaction of the tricyclic quaternary ammonium salts with sodium methoxide leads to the formation of dealkylated and dehydrohalogenated products, 3-substituted 8-chloro-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes, bicyclic products with a halogen atom in an allyl position with respect to the double bond. 相似文献
3.
I. E. Yakunina A. N. Shchukin M. V. Kopyshev I. V. Shakhkel’dyan A. N. Shumskii A. A. Yakovenko K. A. Lysenko Yu. M. Atroshchenko 《Russian Journal of Organic Chemistry》2011,47(6):877-880
Reduction of 6-substituted 1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes gives either saturated 1,5-diamino-3-azabicyclo[3.3.1]nonane
or unsaturated 1,5-diamino-3-azabicyclo[3.3.1]non-6-enes, depending on the conditions and nature of substituent in the substrate. 相似文献
4.
5.
I. V. Shakhkeldyan Yu. M. Atroshchenko N. K. Melekhina I. E. Yakunina K. I. Kobrakov A. N. Shumsky 《Chemistry of Heterocyclic Compounds》2008,44(6):690-699
The electrophilic addition of bromine to 3-substituted 1,5-dinitro-3-azabicyclo[3.3.1]non-6-ene in carbon tetrachloride is
accompanied by intramolecular 3,7-cyclization with the formation of 6-bromo-3-R-1,5-dinitro-3-azonia-tricyclo[3.3.103,7]nonane tribromides. In the bromination of 1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes containing substituents at the double
bond, molecular complexes of halogen with the substrate were obtained.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 862–873, June, 2008. 相似文献
6.
Iurenkov M. V. Potapova T. V. Baranin S. V. Bubnov Yu. N. 《Russian Chemical Bulletin》2021,70(10):1987-1993
Russian Chemical Bulletin - An efficient synthesis of 7-substituted 3-azabicyclo[3.3.1]non-6-enes from available 3-borabicyclo[3.3.1]non-6-enes, the products of allylboron-acetylene condensation,... 相似文献
7.
A series of 2-aryl-3-oxa-1-azaspiro[4.4]non-1-enes was prepared by cyclization of the corresponding β-acylamino alcohols (V) with thionyl chloride. Structure proofs for the β-acylamino alcohols and the spiro compounds are given. Infrared and p.m.r. data are reported. 相似文献
8.
A. P. Molchanov A. V. Stepakov R. R. Kostikov 《Russian Journal of Organic Chemistry》2005,41(1):75-86
Halogenation of 1-substituted 7-aryl-2,3,7-triazabicyclo[3.3.0]oct-2-ene-6,8-diones gives different products, depending on the substituent in position 1 (R1): when R1 = Ar, 6-chloro-3-azabicyclo[3.1.0]hexanes are formed, while compounds with R1 = H or Me give rise to 2- or 4-chloro-2,3,7-triazabicyclo[3.3.0]oct-2-ene-6,8-diones whose thermolysis leads to formation of the corresponding 6-chloro-3-azabicyclo[3.1.0]hexanes. Chlorination of 7-aryl-1,2,7-triazaspiro[4.4]non-1-ene-6,8-diones yields 3-chloro-1,2,7-triazaspiro[4.4]non-1-ene-6,8-diones, and thermolysis of the latter affords 1-chloro-5-azaspiro[2.4]heptanes.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 78–88.Original Russian Text Copyright © 2005 by Molchanov, Stepakov, Kostikov. 相似文献
9.
A two-step synthesis of rare 2-azabicyclo[2.2.2]octanes is described. N-propargyl amides obtained via Cu(I)-catalyzed three-component coupling, underwent radical-mediated cascade cyclization to afford 5,6-aryl-fused 2-azabicyclo[2.2.2]octanes with arylidene functionality on the two-carbon bridge in 43–62% yields. Phenylidene and 1-naphtylidene derivatives were obtained exclusively as Z diastereomers, whereas electron rich groups in the arylidene substituent afforded product mixtures favoring the Z diastereomer by 2.3:1 M ratio. 相似文献
10.
6-Alkylidene-2,3-benzo-1,4-diaza-7-oxabicyclo[4.3.0]non-2-enes were prepared by cyclization of 1,3-bis(silyl enol ethers) with quinoxaline. 相似文献
11.
A versatile method for the synthesis of 4-substituted 6-methyl-3-oxabicyclo[3.3.1]non-6-ene-1-methanol derivatives has been developed using Prins-type cyclization reaction between aldehydes and O-protected/unprotected cyclohex-3-ene-1,1-dimethanol. Under optimized reaction conditions using hafnium triflate, various substrates, including functionalized benzaldehydes and heteroaromatic carbaldehydes, afforded cyclization products in high yields. 相似文献
12.
Yu Chuan Li Si Ping Pang Yong Zhong Yu 《中国化学快报》2007,18(5):516-518
The cyclization reaction of D-aspartic acid was studied, the carboxyl groups of D-aspartic acid were protected by benzyl alcohol to give compound D-dibenzyl aspartate. Then (4R)-benzyl azetidine-2-one-4-carboxylate and meso-3,6-disubstituted piperazine- 2,5-diones were synthesized via intramolecular cyclization and intermolecular cyclization of D-dibenzyl aspartate, respectively, and their structures were confirmed by 1H NMR and MS. Both cyclization reaction conditions were also investigated in detail. 相似文献
13.
E. G. Nikiforova M. A. Korolev I. V. Shakhkel''dyan M. D. Dutov Yu. D. Grudtsyn Yu. M. Atroshchenko S. A. Shevelev V. A. Subbotin 《Russian Journal of Organic Chemistry》2001,37(5):734-738
A number of 7-polyfluoroalkoxy-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes were synthesized by reduction of 3,5-dinitrophenyl polyfluoroalkyl ethers with sodium tetrahydridoborate, followed by the Mannich reaction with formaldehyde and primary amines. 相似文献
14.
Karapetyan V Mkrtchyan S Schmidt A Gütlein JP Villinger A Reinke H Jiao H Fischer C Langer P 《Organic & biomolecular chemistry》2008,6(16):2961-2968
A variety of functionalized 3,4-benzo-7-hydroxy-2,9-diazabicyclo[3.3.1]non-7-enes were prepared by one-pot cyclizations of 1,3-bis(silyl enol ethers) with quinazolines. The mechanism of the cyclization was studied by B3LYP/6-31G(d) density functional theory computations. The products could be functionalized by Suzuki cross-coupling reactions. The reaction of 1,3-bis(silyl enol ethers) with phthalazine afforded open-chain rather than cyclization products. 相似文献
15.
A novel procedure for the synthesis of various derivatives of 6H-chromeno [4, 3-b] quinolines from intramolecular Heck reaction of 2-chloro-3-(phenoxymethyl) quinolines is described in this study. Intramolecular cyclization of N-alkylated indoles was efficiently investigated as well. The reaction is catalyzed by bis (triphenylphosphine) palladium (II) dichloride in acetonitrile at 80 °C. 相似文献
16.
《Tetrahedron letters》1987,28(31):3619-3622
Base-catalysed rearrangement of a 2-alkynyl-tetrahydropyran generates an allenol ether intermediate which undergoes acid-catalysed cyclisation to the 1,6-dioxaspiro[4.5]dec-3-ene system. 相似文献
17.
18.
The new bicyclic systems 1,2-diazabicyclo[3,3,1]nonane and 1,9- diazabicyclo [4,3,0]nonane have been synthesized from 2- (and 3-) piperidineacetic acid via their nitroso-derivatives, and 3-oxo-1,2 diazabicyclo [3,3,1]nonane and 8-oxo-1,9-diazabicyclo[4,3, 0]nonane.For Part III, see [3]. 相似文献
19.
Leonardo Manzoni Laura Belvisi Eliana Di Carlo Carlo Scolastico 《Tetrahedron letters》2004,45(33):6311-6315
By a stereoselective alkylation approach a synthesis of eight enantiopure, sterically constrained Cα-tetrasubstituted azabicycloalkane amino acids was carried out. 相似文献
20.
Moyurima Borthakur 《Tetrahedron letters》2010,51(39):5160-8806
A fast solvent-less synthesis of 5-hydroxy-benzo[g]indole scaffolds is accomplished from Lewis acid-catalyzed one-pot reaction of naphthoquinone, ω-morpholinoacetophenone, and urea under microwave irradiation. The key step in the synthesis is the Michael addition followed by in situ aza cyclization reaction using urea as an environmentally benign source of ammonia. 相似文献