共查询到20条相似文献,搜索用时 62 毫秒
1.
Yellow 9-methyldipyrrinones can be converted readily and in high yields to symmetric linear tetrapyrroles, blue biliverdinoids, which are cleaved in half, smoothly at room temperature to afford yellow 9-H dipyrrinones, and 9-CHO dipyrrinones as their violet to orange colored adducts with the carbon acid used for the scission: thiobarbituric acid (TBA), N,N′-diethylthiobarbituric acid, barbituric acid, N,N′-dimethylbarbituric acid, and Meldrum's acid. The adducts, usually only of passing interest, are formally Knövenagel condensation products of a 9-CHO dipyrrinone with TBA and other carbon acids of this work, and a reverse Knövenagel reaction of such adducts leads to 9-CHO dipyrrinones. Under a set of improved reaction conditions the sequence thus efficiently converts 9-CH3 dipyrrinones to 9-H and 9-CHO dipyrrinones. 相似文献
2.
A simple method for the preparation of 9-alkyl- and 9-arylthio-phenanthrenes from 9-bromophenanthrene and a thiol is described. 相似文献
3.
Conclusions The previously unknown 9-vinyl- and 9-ethynyl-o- and m-carboranes were obtained by the reaction of vinyl- and ethynylmagnesium halides with 9-iodo-o- and 9-iodo-m-carboranes, catalyzed by palladium complexes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 888–892, April, 1985. 相似文献
4.
Walter Fischer 《Helvetica chimica acta》1991,74(5):1119-1126
By aromatic nucleophilic substitution followed by intramolecular acylation, 9-oxo-9H-thioxanthene- and 9-oxo-9H-xanthene-dicarboximides were prepared from nitro- or chlorophthalimides and the dianions of thiosalicylic and salicylic acids (Scheme). The 9-oxo-9H-thioxanthene-3,4-dicarboximides were converted to 9-oxo-9H-thioxanthene-3,4-dicarboxylic-acid derivatives such as anhydride, esters, and further imides. Some of these derivatives proved to be excellent photosensitizers with special properties such as liquid aggregation form, H2O solubility, solubility in lipophilic organic solvents and polymers, or bathochromic shifts of the absorption wavelengths. 相似文献
5.
The synthesis of 9-mesityl-9,10-dihydro-9-boraanthracene is described. Proton abstraction with organolithium reagents gave the title anion, which was converted with various electrophiles into derivatives substituted at C-10. UV spectra indicated the absence of intramolecular coordination of oxygen-containing substituents at C-10 to the Lewis acidic boron centre. The preparation and some properties of the fulvenoid 9-mesityl-10-methylene-9,10-dihydro-9-bora-anthracene and its reaction with tert-butyllithium are reported. 相似文献
6.
Evangelos Kalatzis Zoi Konga Konstantina Geronikolou 《Journal of heterocyclic chemistry》1996,33(3):961-965
In methanol-water mixtures containing sodium or potassium hydroxide (up to 2.00M) the demethoxylation of 9-methoxyacridine to 9-acridone is of first order in both the free form of 9-methoxyacridine and the hydroxyl ion. The rate of the reaction is increased with an increase in the concentration of water. Sodium perchlorate has a small retarding effect on the reaction. In methanol-water mixtures containing perchloric or hydrochloric acid (up to 3.45M) the demethoxylation is of first order with respect to the protonated form of 9-methoxyacridine. The rate of the reaction decreases with an increase in the concentration of the acid or of sodium perchlorate, but when the concentration of water is increased (≈?1.7 to 50M) and that of the acid is not changed, it reaches a maximum value in mixtures containing 8 to 10M-water. The dechlorination of 9-chloroacridine to 9-methoxyacridine in methanol containing sodium hydroxide or methoxide (up to 0.31 M) is of first order in both the 9-chloroacridine and the hydroxyl or methoxyl ions. 相似文献
7.
N. S. Prostakov A. V. Varlamov B. N. Anisimov N. M. Mikhailova G. A. Vasil'ev P. I. Zakharov M. A. Galiullin 《Chemistry of Heterocyclic Compounds》1978,14(9):997-1003
A number of tertiary aza-9-fluorenols were obtained from 4- and 2-azafluofenones and were subjected to dehydration in order to synthesize the previously unknown 9-methyleneazafluorenes. The corresponding 9-methyleneazafluorenes and their polymers were obtained simultaneously in relatively stable form from both pyridine-ring-substituted and -unsubstituted 4-aza-9-fluorenols and from 1,3-diphenyl-2-aza-9-fluorenol. On the basis of an analysis of the mass spectrum of the polymer obtained from 9-methylene-4-azafluorene it was concluded that it is evidently isolated in the form of two dimers — dispiro [bis (4-aza-9-fluorene)-1, 3-cyclobutane] and the analogous product of dispiro addition with a 1,2-substituted cyclobutane ring. Condensation of the corresponding azafluorenes with benzaldehyde gave their 9-benzylidene derivatives in the form of geometrical isomers, the structures of which were established on the basis of the PMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1234–1240, September, 1978. 相似文献
8.
Packing calculations by the atom-atom interaction method are reported for 9-methoxyanthracene (9MeOA) as a guest in host crystalline 9-cyanoanthracene (9CNA). The lower-energy local packing has approximately parallel anthracene nuclei, and substituents in head-to-head (“cis”) registry, in agreement with the structure found experimentally for the photochemical 9MeOA-9CNA complex. Electronic excitation of a host 9CNA adjacent to the guest 9MeOA causes an impulsive, short-lived, displacement of 9CNA*, giving dynamic preformation of either (9CNA)2 excimer, or 9CNA-9MeOA exciplex. Over longer times, the structural response to excitation is followed by calculations including the successive relaxation of neighbour molecules, converging to an equilibrium structure for the locally excited crystal. 相似文献
9.
Les sécrétions de 4 espèces de Dipterocarpus Viêt-Namiens ont fourni un triterpène tétracyclique, identifié au diptérocarpol de van Itallie et à l'hydroxy-dammarénone-II (I) de Mills. Le diptérocarpol est dégradé (chaîne latérale) et modifié (cycle A) en un analogue de la testostérone (XXX). Sa stéréochimie est discutée. 相似文献
10.
9-Trimethylsilylphenanthrene and 9-trimethylsilyl-9,10-dihydroanthracene were synthesized, the latter being photosensitive and oxidizable in exposure to air. When pulverized, the latter electrically charged negative. 相似文献
11.
12.
The regio- and stereo-selective introduction of a difluoromethylene group in an allylic position is described. The key step is the treatment of 1,1-difluoro-1-alken-3-acetates with Grignard reagents in the presence of copper and lithium salts.
Résumé
Nous décrivons ici une méthode régio- et stéréo-sélective permettant l'introduction du groupement difluorométhylène en position allylique. L'étape principale est la réaction des 3-acétoxy-1,1-difluoro-1-alcènes avec les réactifs de Grignard en présence de sels de cuivre et de lithium. 相似文献
13.
14.
9-Benzoylanthracene and 9-anthryl styryl ketone disproportionate to anthracene and the corresponding 9,10-diacylanthracene when warmed in carbon disulphide or nitrobenzene with an excess of aluminium chloride. The reactions are co-catalysed by hydrogen chloride. Comparison is made with other 9-anthryl ketones and with 1-naphthyl styryl ketone, which undergo different reactions under similar conditions. The results are interpreted in terms of steric requirements. 相似文献
15.
Unsymmetrical 9-chloro-9-phosphafluorenes (dibenzophospholes) and 9-chloro-9-arsafluorenes (dibenzoarsoles) have been obtained by simple thermolysis of m-terphenyldichlorophosphines and -arsines in close to quantitative yields. The reaction temperatures are about 200 degrees C for the phosphines and 140 degrees C for the arsine, and the reactions are complete within 5 min. Alternatively, these compounds can be synthesized through an AlCl3-catalyzed Friedel-Crafts type ring-closure reaction at low temperatures, but this method suffers from difficult workup procedures. The P(As)-Cl functionality is readily alkylated. Methylation of m-xylyl derivative 4 afforded 1-(3,5-dimethylphenyl)-6,8,9-trimethyl-9-phosphafluorene, 11. The latter compound formed the complexes 11 x Fe(CO)4, 12, and 11 x RuCl2(eta(6)-p-cymene), 13, indicating its good donor properties. The new compounds have been characterized by 1H, 13C{1H}, and 31P{1H} NMR spectroscopy; mass spectrometry; and single-crystal X-ray crystallography in the case of 11, 12, and 13. 相似文献
16.
V. D. Filimonov V. A. Anfinogenov E. E. Sirotkina 《Chemistry of Heterocyclic Compounds》1979,15(4):404-408
A number of 9-alkenylcarbazoles were obtained in good yields by elimination of alcohols from 9-(l-alkoxyalkyl)carbazoles by heat treatment and under the influence of catalysts. The method makes it possible to obtain both pure trans isomers and mixtures of cis-trans isomers of disubstituted 9-alkenylcarbazoles. The trans isomers of N-propenyl derivatives of pyrrolidone and caprolactam were similarly obtained. The fact of the catalysis of the electrophilic addition of alcohols to 9-alkenylcarbazoles by carbon tetrachloride was observed.See [1] for communication 4.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 497–502, April, 1979. 相似文献
17.
Mingwu Yu Xiguang Liu Qingsong Jiang Hongguang Du 《Phosphorus, sulfur, and silicon and the related elements》2018,193(7):451-458
An expeditious and convenient method to synthesize 9-allenylpurines via cesium carbonate catalyzed isomerization of 9-alkynylpurines has been successfully developed. The reactions proceeded rapidly under the base conditions and formed the desired products in good to excellent yields. The method was suitable with a broad substrate scope and proceeded well even on a multgram-scale. The obtained 9-allenylpurines were successfully applied to prepare various potential bioactive 9-acyclic nucleosides with high regioselectivity promoted by AgNO3. 相似文献
18.
Maria Rosaria Del Giudice Anna Borioni Carlo Mustazza Franco Gatta 《Journal of heterocyclic chemistry》1997,34(6):1661-1667
This paper describes the synthesis of 9-amino-2- and 4-hydroxy- and 2,4-dihydroxy-1,2,3,4-tetrahydro-acridines 2 and of 9-aminomethyl-1,2,3,4-tetrahydro- and 1,2,3,4,5,6,7,8-octahydroacridines 3 starting from the corresponding 9-carboxamido derivatives. A new synthetical pathway to 9-amino-2-hydroxyacri-dine 9 is also reported. 相似文献
19.
Structure of 6,11-dichloro-9-dimethylthio-7,8-dicarba-nido-undecaborane [6,11-Cl2-9-SMe2-7,8-C2B9H9]
O. N. Kazheva D. A. Rudakov G. V. Shilov O. A. D’yachenko V. I. Potkin 《Journal of Structural Chemistry》2013,54(2):349-354
A technique is proposed for directed synthesis of 6,11-dichloro-9-dimethylthio-7,8-dicarba-nido-undecaborane [6,11-Cl2-9-SMe2-7,8-C2B9H9]. Single-crystal X-ray diffraction is used to identify the molecular and crystal structure of the compound. 相似文献
20.
Eugene B. Grant Jesse M. Weiss Shawn Branum Stuart Hayden Sigmond Johnson Deodialsingh Guiadeen William V. Murray Mark J. Macielag 《Tetrahedron letters》2005,46(16):2731-2735
A short, concise synthesis of a novel series of (9S)-9-alkyl-9-hydroxyerythromycin A derivatives and their corresponding ketolides, is described. The key chemical transformation is a stereoselective addition of organomagnesium or organolithium agents to the 9-position of the suitably protected macrolide templates 8 and 13. 相似文献