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1.
2.
Airat M. Gimazetdinov Salavat S. Gataullin Ivan S. Bushmarinov Mansur S. Miftakhov 《Tetrahedron》2012,68(29):5754-5758
Diastereomeric amides produced via the cleavage of easily available (±)-7,7-dichloro-4-exo-trimethylsilylbicyclo[3.2.0]hept-2-en-6-one by treatment with (+)-α-methylbenzylamine were transformed into bicyclic lactam-aminals, which can easily be separated by column chromatography on SiO2. The latter products lead to enantiomeric (3a,6a)-4-hydroxy-3,3a,4,6a-tetrahydro-1H-cyclopenta[c]furan-1-ones after the removal of the chiral auxiliary and epoxidation. 相似文献
3.
The condensation reaction between 5-amino-4,6-dichloro-2-methylprimidine and 1-acetyl-2-imidazolin-2-one using POCl3 as solvent gave 4,6-dichloro-2-methyl-5-(1-acetyl-tetra-hydro-imidazo-2-ylidene)-aminopyrimidine predominantly and 4,6-dichloro-2-methyl-5-{1-1-(2-oxo-tetrahydro-imidazolyl)]-acetene}-aminopyrimidine as by-product. No 4,6-dichloro-2-methyl-5-(1-acetyl-2-imidazolin-2-yl)-aminopyrimidine was found. The result indicated an esterifi-cation-addition-elimination mechanism. 相似文献
4.
I. A. Abronin L. G. Gorb V. G. Dryuk V. I. Sheremet Z. F. Solomko M. M. Kremlev 《Chemistry of Heterocyclic Compounds》1981,17(9):954-956
The results of the chlorination of 4-methyl-8-methoxy-2,3-dihydro-1H,1,5-benzodiazepin-2-ones are compared with the results of quantum-chemical calculations of 4-methyl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones with various substituents in the benzene ring in the case of homolytic halogenation. The chlorination of 4-methyl-8-methoxy-2,3-dihydro-1H-1,5-benzodiazepin-2-one (I) with N-chlorosuccinimide leads to 3-chloro- and 3,3-dichloro-4-methyl-8-methoxy-2,3-dihydro-1H-1,5-benzodiazepin-2-ones, whereas chlorination with sulfuryl chloride leads to 4-chloromethyl and 3,3-dichloro-4-methyl derivatives. The IR, PMR, and mass spectra of the synthesized compounds are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1272–1274, September, 1981. 相似文献
5.
Fillmore Freeman Behrooz Entezam Timothy S. Welch 《Journal of organometallic chemistry》2005,690(18):4103-4113
Second-order Møller-Plesset theory (MP2) and density functional theory (B3LYP) with the 6-311G(d,p) and 6-311+G(d,p) basis sets have been used to calculate the equilibrium geometries and relative energies of the chair, twist, and boat conformations of 4-chloro-4-silathiacyclohexane 1-oxide and 4,4-dichloro-4-silathiacyclohexane 1-oxide. The chair conformers of the axial sulfoxides are lower in energy than the chair conformers of the corresponding equatorial sulfoxides. MP2/6-311+G(d,p) predicted the chair conformer of axial trans-4-chloro-4-silathiacyclohexane 1-oxide (4a) to be 6.12, 0.44, and 0.45 kcal/mol, respectively, more stable than the corresponding 1,4-twist (4b), 2,5-twist (4c) and 1,4-boat (4d) conformers and 6.93 kcal/mol more stable than the 2,5-boat transition state ([4e]‡). Structures 4c and 4d are stabilized by intramolecular coordination of the sulfinyl oxygen with silicon that results in trigonal bipyramidal geometry at silicon. The 1,4-boat conformer (7d) of axial 4,4-dichloro-4-silathiacyclohexane 1-oxide is also stabilized by transannular coordination of the sulfinyl oxygen with silicon. The energy difference (Erel = 4.23 kcal/mol) between the chair conformer (7a) and 7d is larger than that between 4a and 4d. The relatively lower stability of the 1,4-boat conformer (7d) of axial 4,4-dichloro-4-silathiacyclohexane 1-oxide (7a) may be due to repulsive interactions of the axial halogen and sulfinyl oxygen atoms. The relative energies and structures of the conformers and transition states of cis- and trans-4-chloro-4-silathiacyclohexane 1-oxide and 4,4-dichloro-4-silathiacyclohexane 1-oxide are discussed in terms of hyperconjugative interactions, orbital interactions, nonbonded interactions, and intramolecular sulfinyl oxygen-silicon coordination. 相似文献
6.
É. K. Orlova V. A. Zagorevskii I. D. Tsvetkova 《Chemistry of Heterocyclic Compounds》1970,6(9):1088-1091
Reaction of 4, 4-dichloroflavine (I) with sulfurylchloride affords 2, 3, 3, 4, 4-pentachloroflavan (II). Hydrolysis of II gives 2-hydroxy-3, 3-dichloro-4-flavanone (III), while alcoholysis with aqueous alcohols yields 2-alkoxy-3,3-dichloro-4-flavanones (IVa, b). Treatment of III with SOCl2 gives 2,3,3-trlchloro-4-flavanone (V), which with caustic alkali or sodium ethoxide is converted into o-(1-phenyl-2, 2-dichlorovinyloxy)benzoic acid (VIc) or its ethyl ester (VIb), respectively.For Part XLII, see [7].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1167–1170, September, 1970. 相似文献
7.
V. Yu. Serykh I. B. Rozentsveig G. N. Rozentsveig K. A. Chernyshev 《Chemistry of Heterocyclic Compounds》2012,47(11):1339-1344
The C-amidoalkylation of p-cresol with 4-chloro-N-(2,2-dichloro-2-phenylethylidene)benzenesulfon-amide in the presence of H2SO4, oleum, or a mixture of H2SO4 and P4O10 was studied for the first time. It was shown that the reaction not only leads to the targeted 4-chloro-N-[2,2-dichloro-1-(2-hydroxy-5-methylphenyl)-2-phenylethyl]benzenesulfonamide but is also accompanied by unexpected formation
of the heterocyclic derivatives 4-chloro-N-(5-methyl-2-phenyl-1-benzofuran-3-yl)benzenesulfonamide and 5-methyl-3-phenyl-2-benzofuran-2(3H)-one. 相似文献
8.
Nabih S. Girgis Roland K. Robins Howard B. Cottam 《Journal of heterocyclic chemistry》1990,27(7):1989-1991
Nucleosides of pyrrolo[2,3-d]pyridazin-4(5H)-ones were prepared by the single-phase sodium salt glycosylation of appropriately functionalized pyrrole precursors. The glycosylation of the sodium salt of ethyl 4,5-dichloro-2-formyl-1H-pyrrole-3-carboxylate ( 4 ), or its azomethino derivative 7 , with 1-bromo-2,3,5-tri-O-benzoyl-D-ribofuranose in acetonitrile afforded the corresponding substituted pyrrole nucleosides ethyl 4,5-dichloro-2-formyl-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-1H-pyrrole-3-carboxylate ( 5 ) and ethyl 4,5-dichloro-2-phenylazomethino-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)-1H-pyrrole-3-carboxylate ( 8 ), respectively. The latter, upon treatment with hydrazine, afforded the annulated product 2,3-dichloro-1-β-D-ribofuranosyl-1H-pyrrolo[2,3-d]pyridazin-4(5H)-one ( 6 ), in good yield. The unsubstituted analog 1-β-D-ribofuranosyl-1H-pyrrolo[2,3-d]pyridazin-4(5H)-one ( 9 ), was obtained upon catalytic dehalogenation of 6 . This report represents the first example of the synthesis of nucleosides of pyrrolopyridazines. 相似文献
9.
G. Märkl H. Baier P. Hofmeister F. Kees C. Soper 《Journal of organometallic chemistry》1979,173(2):125-169
The 1(Z),4(Z)-1,5-dilithium-3R-3-methoxypenta-1,4-dienes, available by cleavage of 1,1-di-n-butyl-4R-4-methoxy-1-stannacyclohexane-2,5-dienes with n-BuLi in ether, react with dichlorosilanes (R′R″ SiCl2; R′, R″ = H, alkyl, aryl, alkoxy) to give 1R′,1R″,4R-4-methoxy-1-silacyclohexa-2,5-dienes.Claevage of the ether group with BBr3, BCl3 or PCl3 gives 6-chloro(bromo)-1-silacyclohexa-2,4-dienes or 1,5-dichloro-1-silacyclohexane-2,4-dienes, respectively.Ether cleavage of 4R-4-methoxy-1-silacyclohexa-2,5-dienes with sodium results in the formation of 4R-1-silacyclohexadienyl anions, which can be hydrolyzed to give 1-silacyclohexa-2,4-dienes which reach further with trichloromethylsilane to give 6-trimethylsilyl-1-silacyclohexa-2,4-dienes.Phase transfer-catalyzed conversion of 1-chlorosilacyclohexadienes into the fluoro derivatives as well as further substitution reactions of 1-chlorosilacyclohexadienes are described.The 1H NMR, 13C NMR, IR and mass spectra of the silacyclohexadienes are discussed. 相似文献
10.
I. A. Strakova A. Ya. Strakov M. V. Petrova L. G. Delyatitskaya 《Chemistry of Heterocyclic Compounds》2000,36(4):459-464
Reaction of the potassium salt of 2-formyldimedone with hydrochlorides of 4-chloro-, 3-chloro-, 2-chloro-, 2,4-dichloro-, and 2,4-difluorophenylhydrazines gave the corresponding 2-arylhydrazinomethylene-dimedones which cyclized in acid media to 1-substituted 6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazoles. Oxidation of the latter with selenious acid gave the corresponding 4,5-dioxo-4,5,6,7-tetrahydroindazoles which were further converted into 3-aryl-5,5-dimethyl-4,5-dihydro-3H-pyrazolo[4,3-a]phenazines and 2,6-diaryl-4,4-dimethyl-4,5-dihydro-1H(3H)-indazolo[4,5-g]imidazoles.Riga Technical University, Riga LV-1658, Latvia; e-mail: marina@osi.lv. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, 533–539, April, 2000. 相似文献
11.
The syntheses of 1, 2-annelated 1, 4-benzodiazepines (IV, Y = N) and 4, 1-benzoxazepines (IV, Y = 0) are described (Scheme 1). The key step is a nucleophilic aromatic substitution of 2-substituted piperazines (II, Z = N? CH3), piperidines (II, Z = CH2) or pyrrolidines (II, Z= (CH2)0) with activated aryl halides (I). 相似文献
12.
V. I. Potkin V. A. Knizhnikov A. A. Yanuchok R. V. Kaberdin 《Russian Journal of Organic Chemistry》2001,37(5):640-643
The reactions of 4-ethoxy-2-(2,3,3-trichloro-1-nitro-2-propenylidene)benzazetine with methyl- and phenyllithium at a ratio of 1:2 result in replacement of one chlorine atom and formation, respectively, of 4-ethoxy-2-(2,3-dichloro-3-methyl-1-nitro-2-propenylidene)benzazetine and 4-ethoxy-2-(2,3-dichloro-1-nitro-3-phenyl-2-propenylidene)benzazetine in 45 and 52% yield. With excess phenyllithium (reactant ratio 1:5), a mixture of products is formed due to replacement of one, two, and three chlorine atoms by phenyl groups. An analogous reaction with methyllithium is nonselective. 相似文献
13.
I. Strakova M. Petrova S. Belyakov A. Strakovs 《Chemistry of Heterocyclic Compounds》2003,39(12):1608-1616
The interaction of 3-formyl-4-coumarin with arylhydrazine hydrochlorides in the presence of sodium acetate gave the corresponding 3-arylhydrazonomethyl-4-chlorocoumarin, and with phenylhydrazine, 4-bromo- and 4-chlorophenylhydrazine hydrochlorides in the presence of two equivalents of triethylamine gave either 1-aryl- or 2-aryl[1]benzopyrano[4,3-c]pyrazol-4-ones depending on the reaction conditions. In reactions of 4-chloro-3-formylcoumarin with 2,4-dichloro-, 2,4-difluoro-, 2-hydroycarbonyl-, 4-nitro- and 3,5-di(trifluoromethyl)phenylhydrazine, 2-pyridyl- and 2-quinoxalylhydrazine in the presence of excess of triethylamine the 2-aryl[1]benzopyrano[4,3-c]pyrazol-4(2H)-ones were obtained exclusively. The structures of 1-phenyl- and 2-(2-pyridyl)[1]benzopyrano[4,3-c]pyrazolo-4(1H)ones were confirmed by X-ray crystallography. A simple method is proposed to distinguish between 1- and 2-substituted [1]benzopyrano[4,3-c]pyrazolo-4-ones on the basis of the 1H NMR chemical shifts of the C(3)-H proton in two solvents - DMSO-d6 and CDCl3. 相似文献
14.
Cédric KleinEtienne Baranoff Michael GrätzelMd. Khaja Nazeeruddin 《Tetrahedron letters》2011,52(5):584-587
Citrazinic acid is used as a convenient starting material for both tridentate 2,6-di(pyrazol-1-yl)-pyridine and tetradentate 6,6′-di(pyrazol-1-yl)-2,2′-bipyridine ligands containing carboxylic groups useful for further anchoring of sensitizer on TiO2 for dye-sensitized solar cells (DSCs). Using 2,6-dichloro-4-carboxypyridine, the synthesis of the terdentate ligands was improved compared to previously used 2,6-dibromo-4-carboxypyridine or 2,6-dichloro-4-ethylcarboxylate pyridine. Controlling the reaction conditions, it is possible to efficiently obtain the monosubstituted 2-chloro-6-pyrazol-1-yl-4-carboxypyridine, a key intermediate for the preparation of tetradentate 6,6′-di(pyrazol-1-yl)-4,4′-dicarboxy-2,2′-bipyridine ligand. 相似文献
15.
V. I. Potkin S. K. Petkevich R. V. Kaberdin P. V. Kurman 《Russian Journal of Organic Chemistry》2004,40(10):1508-1511
Reaction of 1,1,4,4-tetrachloro-3-buten-2-one with 3,5-dimethylpyrazole gave 1,1-dichloro- 4,4-bis-(3,5-dimethyl-1-pyrazolyl)-3-buten-2-one. Treatment of the latter with amines resulted in replacement of one pyrazole ring by the amine residue with formation of the corresponding 4-amino-1,1-dichloro-4-(3,5- dimethyl-1-pyrazolyl)-3-buten-2-ones.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 10, 2004, pp. 1557–1560.Original Russian Text Copyright © 2004 by Potkin, Petkevich, Kaberdin, Kurman. 相似文献
16.
Treatment of 1-alkyl-4,5-dichloro-3-nitropyridazin-6-one with C-nucleophiles and with ambident nucleophiles (2-azahetarylacetonitriles)
leads to a selective substitution of a chorine atom by the quaternary carbon atom of the carbanion formed from a substituted
acetonitrile. The pKa of the CH-acid 2-(1-alkyl-5-chloro-3-nitro-6-oxo-1,6-dihydro-4-pyridazinyl)malononitrile was determined by potentiometric
titration. Reaction of 2-(1-alkyl-5-chloro-3-nitro-6-oxo-1,6-dihydro-4-pyridazinyl)-2-hetarylacetonitriles with primary amines
gives 6,7-dihydro-1H-pyrrolo[2,3-d]pyridazin-7-ones.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 556–564, April, 2006. 相似文献
17.
Potkin V. I. Petkevich S. K. Kaberdin R. V. Tychinskaya L. Yu. 《Russian Journal of Organic Chemistry》2002,38(9):1271-1276
Reaction of 3,4,4-trichloro-1-(4-methylphenyl)-3-buten-1-one with amines results in replacement of the internal chlorine atom and is accompanied by prototropic allyl rearrangement leading to formation of the corresponding 3-amino-4,4-dichloro-1-(4-methylphenyl)-2-buten-1-ones. The reaction of the title compound with 2,4-dinitrophenylhydrazine yields 3,4,4-trichloro-1-(4-methylphenyl)-3-buten-1-one 2,4-dinitrophenylhydrazone and is not accompanied by allyl rearrangement. 相似文献
18.
Synthesis of the Silatetraphospholanes (tBuP)4SiMe2, (tBuP)4SiCl2, and (tBuP)4Si(Cl)SiCl3 Molecular and Crystal Structure of (tBuP)4SiCl2 The reaction of the diphosphide K2[(tBuP)4] 7 with the halogenosilanes Me2SiCl2, SiCl4 or Si2Cl6 in a molar ratio of 1:1 leads via a [4 + 1]-cyclocondensation reaction to the silatetraphospholanes (tBuP)4SiMe2 1,1-dimethyl-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholane, 1 , (tBuP)4SiCl2, 1,1-dichloro-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholane, 2 , and (tBuP)4Si(Cl)SiCl3, 1-chloro-1-trichlorsilyl-1-sila-2,3,4,5-tetra-t-butyl-2,3,4,5-tetraphospholane, 3 , respectively, with the 5-membered P4Si ring system. The reaction leading to 1 is accompanied with the formation of the by-product Me2(Cl)-Si–(tBuP)4–Si(Cl)Me2 1a (5:1), which has a chain structure. On warming to 100°C 1a decomposes to 1 and Me2SiCl2. The compounds 2 and 3 do not react further with an excess of 7 due to strong steric shielding of the ring Si atoms by the t-butyl groups. 1, 2 and 3 could be obtained in a pure form and characterized NMR spectroscopically; 2 was also characterized by a single crystal structure analysis. 1a was identified by NMR spectroscopy only. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(11):2004-2011
The reaction of Cu(Ac)2·4H2O with 2-[(3,5-dichloro-2-hydroxy-benzylidene)-amino]-2hydroxymethyl-propane-1,3-diol (H4L) and 4,4′-bipyridyl-N,N′-dioxide (4,4′-bipy-NO) in DMF under solvothermal conditions leads to the formation of a di-radical dinuclear copper complex [Cu2(4,4′-bipy-NO)(dcdmap)4] (1) (dcdmap is the anion of 2,4-dichloro-6dimethylaminomethyl-phenol, synthesized by an in situ reaction). Compound 1 was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 displays dominant anti-ferromagnetic interaction between oxyradicals and copper ion and oxyradical. 相似文献
20.
Chuanxiang Liu Yong Chen Yingxin Sun Fanhong Wu 《Research on Chemical Intermediates》2013,39(5):2087-2093
The crystal structure of 1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-6-ethyl-1H-pyrazolo[3,4-b]pyridine-3-carbonitrile was obtained and determined by X-ray crystallography. The reaction mechanism of 5-amino-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-1H-pyrazole-3-carbonitrile with unsaturated carbonyl compounds was further proposed. 相似文献