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1.
Russian Chemical Bulletin - 1,3-Dimethoxy- 1,3-dimethyl- 1,3-diphenyl- and 1,3-dimethoxy- 1,3-tetraphenyldisiloxanes were synthesized. Their structures were confirmed by IR and NMR spectroscopy.... 相似文献
2.
We present the first synthesis and characterization of a 1,3-dihydro-1,3-azaborine, a long-sought BN isostere of benzene. 1,3-Dihydro-1,3-azaborine is a stable structural motif with considerable aromatic character as evidenced by structural analysis and its reaction chemistry. Single crystal X-ray analysis indicates bonding consistent with significant electron delocalization. 1,3-Dihydro-1,3-azaborines also undergo nucleophilic substitutions at boron and electrophilic aromatic substitution reactions. In view of the versatility and impact of aromatic compounds in the biomedical field and in materials science, the present study further expands the available chemical space of arenes via BN/CC isosterism. 相似文献
3.
Kazem Shiroodi R Dudnik AS Gevorgyan V 《Journal of the American Chemical Society》2012,134(16):6928-6931
A double migratory cascade reaction of α-halogen-substituted propargylic phosphates to produce highly functionalized 1,3-dienes has been developed. This transformation features 1,3-phosphatyloxy group migration followed by 1,3-shifts of bromine and chlorine as well as the unprecedented 1,3-migration of iodine. The reaction is stereodivergent: (Z)-1,3-dienes are formed in the presence of a copper catalyst, whereas gold-catalyzed reactions exhibit inverted stereoselectivity, producing the corresponding E products. 相似文献
4.
The photochemical behavior of 2-halo-substituted 1,3-diarylpropan-1,3-dione strongly depends on the nature of the halogen atom bonded and the presence of electron-donor groups on the phenyl ring. In the case of 2-chloro-1,3-diphenylpropan-1,3-dione and 1-(3,5-dimethoxyphenyl)-3-phenylpropan-1,3-dione, cyclization to flavones was the sole reaction pathway, whereas in the case of 2-chloro-1,3-di(4-methoxyphenyl)propan-1,3-dione, only products derived from alpha-cleavage were observed. 2-Fluoro derivatives of 1,3-diarylpropan-1,3-diones were photostable; on the other hand, 2-chloro-2-fluoro derivates resulted in 3-fluoroflavones. 相似文献
5.
The title compound 2 was prepared by thermal dehydration of 1,3-diferrocenyl-1,3-diphenyl-propenol (24) with 70% yield.24 was accessible from 1,3-diferrocenyl-propanedione-1,3 (25) in two steps with 10% overall yield: Treatment of25 with phenyllithium gave 1,3-diferrocenyl-3-phenyl-propenone (8) which after repeated reaction with phenyllithium afforded24.Partial optical resolution of2 was achieved by chromatography on triacetyl cellulose in ethanol, whereby both (+)- and (–)-2 were obtained with different enantiomeric purities as could be deduced from the CD-spectra with -values of +0.18 and –1.64, resp., at 480 nm.Attempts to prepare 1,3-diferrocenyl-allene and 1,3-diferrocenyl-1-phenyl-allene failed. In this context several 1,3-diferrocenyl-propenols,-propenones,-propenes,-propanones,-propanes and-butadienes were obtained.
62. Mitt.:M. Benedikt undK. Schlögl, Mh. Chem.109, 805 (1978). 相似文献
6.
1,3-Dihalo-1,3-dioximino-2-propanones (Hal=Cl or Br), which had been difficult to prepare or unreported, were obtained by the nitrosation of 1,3-dihalo- and 1,3-dihalo-1-oximino-2-propanones by nitrosylsulfuric acid in concentrated H2SO4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 506–509, February, 1991. 相似文献
7.
J. Thorbjørnsrud O.H. Ellestad P. Klaboe T. Torgrimsen 《Journal of Molecular Structure》1973,15(1):61-76
The infrared and Raman spectra of 1,3-dichloro-, 1,3-bromochloro-, 1,3-dibromo- and 1,3-diiodopropane were recorded as liquids and in the crystalline state at low temperatures. Crystals of 1,3-dibromo- and 1,3-diiodopropane formed under ca. 20 kbar pressure at ambient temperature were studied by infrared technique.No evidence was found for the GG1 conformer (parallel C-halogen bonds), but the other three staggered conformers (GG, AA, and AG) (four for 1,3-bromo-chloropropane) were observed in the liquid. In all the stable low temperature crystals the GG conformers were present, at high pressure 1,3-dibromopropane crystallized in GG and 1,3-diiodopropane in the AA conformation. The C-halogen stretching vibrations have been interpreted in detail. A complete list of fundamentals have been proposed for the GG conformers in each compound, for 1,3-diiodopropane the additional AA fundamentals have been assigned whereas some AG bands were interpreted for each compound. 相似文献
8.
A. A. Turmasova V. V. Konshin Dzh. N. Konshina 《Russian Journal of General Chemistry》2014,84(7):1273-1276
Reactions of 1,3-dihydroxyadamantane with 1,3-dicarbonyl compounds in the presence of 5 mol % of In(OTf)3 afforded a series of (1,3-adamantylene)bis-1,3-dicarbonyl compounds in yields of 25–83%. 相似文献
9.
Giorgio Abbiati Alessandro Contini Donatella Nava Elisabetta Rossi 《Tetrahedron》2009,65(24):4664-3418
The cycloaddition reactions of ‘all-carbon’ 1,3-diazabuta-1,3-dienes with a few conjugated and unconjugated alkynyl ketenes are described. The reactions provide some interesting azetidinones and dihydropyrimidinones bearing an alkynyl moiety. The regiochemistry of cycloadduct is related with the degree of conjugation of the alkynyl ketene. Moreover, two alternative approaches to ‘all-carbon’ 1,3-diazabuta-1,3-dienes are reported. 相似文献
10.
Carbon-13 nmr spectra of several 1,3-oxathiolane, 1,3-oxathiolane-3-oxide and 1,3-oxathiolane-3,3-dioxide derivatives are reported. Relationships between some stereochemical features and chemical shift are discussed. 相似文献
11.
Amii H Vranicar L Gornitzka H Bourissou D Bertrand G 《Journal of the American Chemical Society》2004,126(5):1344-1345
Despite through-space and through-bond B-B interactions, the stable 1,3-bora-2,4-diphosphoniocyclobutane-1,3-diyl displays some radical-type behavior, as illustrated by the spontaneous formation of the trans 1,3-adduct with trimethyltin hydride and a B-spiro derivative with bromotrichloromethane. 相似文献
12.
Ming-Chang P. Yeh Chi-Fen Jou Wei-Tzou Yeh Da-Yu Chiu N. Ravi Kumar Reddy 《Tetrahedron》2005,61(2):493-500
Intramolecular 1,3-dipolar cycloaddition of cyclo-1,3-diene- and -1,3,5-triene-tethered nitrile oxides gave tricyclic isoxazolines as a single stereoisomer in most cases. The relative stereochemistry of tricycle-fused isoxazolines resulting from 1,3-dipolar cycloaddition of cyclo-1,3-diene-tethered nitrile oxides is cis-cis, whereas from cyclohepta-1,3,5-triene-tethered nitrile oxides the cis-trans isomer predominates. 相似文献
13.
David Thomae Zhanjie Xu Serge Schneider Gilbert Kirsch Pierre Seck 《Tetrahedron》2009,65(15):2982-9357
In this work, we describe the synthesis of new 2,4,5-trisubstituted-1,3-thiazoles and 1,3-selenazole achieved by an easy one-pot four-step procedure. Expected compounds were obtained in good yield from dimethyl cyanodithioimidocarbonate, which was the common starting material for the preparation of all 1,3-thiazoles and 1,3-selenazoles. Chemical diversity was introduced on thiazole and selenazole rings by varying the amines and the activated halides used. 相似文献
14.
Alexander V. Stepakov Jörg Magull Galina L. Starova Rafael R. Kostikov 《Tetrahedron》2006,62(15):3610-3618
Treatment of substituted 1,3-dithiolanes and 1,3-oxathiolanes with methyl diazoacetate in the presence of Rh2(OAc)4 effects ring expansion to the corresponding substituted 1,4-dithiane-2-carboxylates and 1,4-oxathiane-3-carboxylates. The sulfur ylides initially generated in these reactions undergo Stevens rearrangement in competition with both [2,3]-C-C-sigmatropic rearrangement and intramolecular fragmentation. In the case of 2-styryl-substituted 1,3-oxathiolane and 1,3-dithiolane, ring expansion on one-, three- and four-carbons subsequently takes place. 相似文献
15.
Masahiko Okada Masaaki Uno Hiroshi Sumitomo 《Journal of polymer science. Part A, Polymer chemistry》1973,11(6):1237-1248
Copolymerization of 2-vinyl-1,3-dioxane with styrene and 1,3-dioxolane was carried out in methylene chloride at 0°C with triethyloxonium tetrafluoroborate as an initiator. Random copolymers were obtained from both of these monomer pairs, but attempted copolymerization of 2-vinyl-1,3-dioxane with 3,3-bis(chloromethyl)oxetane under similar conditions resulted in the homopolymer of the latter monomer. There were three structural units of 2-vinyl-1,3-dioxane in these copolymers as in its homopolymer: the “ester” unit, which was formed by vinyl addition with hydride shift followed by ring-opening rearrangement, the “vinyl” unit produced by ring-opening reaction, and the unit with a pendant 1,3-dioxane ring formed by simple vinyl addition. The fractions of the ester and vinyl units to the total 2-vinyl-1,3-dioxane units in the copolymer of 2-vinyl-1,3-dioxane with styrene decreased with decreasing 2-vinyl-1,3-dioxane content. On the contrary, the fraction of the vinyl unit in the copolymer of 2-vinyl-1,3-dioxane with 1,3-dioxolane increased slightly with decreasing 2-vinyl-1,3-dioxane content, while that of the ester unit decreased. The reactivities of the propagating species are discussed on the basis of these results. 相似文献
16.
V. O. Sinenko S. R. Slivchuk O. P. Mityukhin V. S. Brovarets 《Russian Journal of General Chemistry》2017,87(12):2766-2775
H-Lithiation and Br-lithiation reactions of 1,3-thiazole were studied in order to obtain new thiazole derivatives. Four isomeric chloromethyl derivatives of 1,3-thiazole containing a protected aldehyde group like 2-(1,3-dioxolan-2-yl)-5-(chloromethyl)-1,3-thiazole, 5-(1,3-dioxolan-2-yl)-2-(chloromethyl)-1,3-thiazole, 4-(1,3-dioxolan-2-yl)-2-(chloromethyl)-1,3-thiazole, and 2-(1,3-dioxolan-2-yl)-4-(chloromethyl)-1,3-thiazole were synthesized. Their nucleophilic substitution reactions with dimethylamine and sodium methylthiolate were studied. New aldehydes of 1,3-thiazole series of low-molecular weight were obtained. 相似文献
17.
R. F. Ambartsumova B. Tashkhodzhaev M. K. Makhmulov 《Chemistry of Heterocyclic Compounds》1997,33(4):475-480
Addition of 2-aryliminohexahydro-1,3-thiazepines to methyl acrylate occurs with participation of the endocyclic nitrogen atom.
Structures of the products have been established by IR and mass spectroscopy and x-ray diffraction. The previously described
2-benzylaminotetrahydro-1,3-thiazepine is in fact 2-benzyliminohexahydro-1,3-thiazepine.
For Communication 3 see [1].
Institute of Phytochemistry, Academy of Sciences, Republic of Uzbekistan, Tashkent 700170. Translated from Khimiya Geterotsiklicheskikh
Soedinenii, No. 4, 554–559, April, 1997. 相似文献
18.
A.N. Nesmeyanov E.V. Leonova N.S. Kochetkova A.I. Malkova A.G. Makarovskaya 《Journal of organometallic chemistry》1975,96(2):275-278
A method is described for the preparation of 1,3-diacetylferrocene, in which ethylferrocene is first acetylated with acetyl chloride in the presence of AlCl3 in methylene chloride to a mixture of isomeric acetylethylferrocenes. This mixture is then subjected to thin-layer chromatography, a mixture of the 1,1′- and 1,3-derivatives free from the 1,2-isomer being obtained. After oxidation of this mixture with MnO2 to a mixture of 1,1′- and 1,3-diacetylferrocenes, the isomers are separated by preparative thin-layer chromatography. 相似文献
19.
1-Aminopyrroles (4) are obtained by reaction of 1,2-diazabuta-1,3-dienes (1) and ynamines (2). This reaction represents one of the very rare examples of 1,3-cycloaddition processes of alkynes and hetero-1,3-dienes. 相似文献
20.
The reaction of 1,3-diphenylbarbituric and 1,3-diphenyl-2-thiobarbituric acids with diazotized sulfaniiimides gives 1,3-diphenylalloxan and 1,3-diphenyl-2-thioalloxan phenylhydrazones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1276–1279, September, 1971. 相似文献