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1.
The decomposition of various symmetric and unsymmetric azo-initiators (1,1-dichloro-1,1-diphenyl-1,1-azoethane, 2,2-dichloro-2,2-azopropane, 1,1-dichloro-1,1-azocyclohexane, 2,2-diacetoxy-2,2-azopropane, 1,1-diacetoxy-1,1-diphenyl-1,1-azoethane, 1,1-diacetoxy-1,1-azocyclohexane, 2,2-dipropionoxy-2,2-azopropane, 2,2-dicapronoxy-2,2-azopropane, 4,4-dimethyl-1,4-azobutyrolactone, azoisobutyronitrile, 2-t-butylazo-2-cyanobutan, 2-t-bytylazo-1-cyanocyclohexan) in solution was studied in dependence of temperature. Volumetry and differential-scanning-calorimetry (DSC) were used to determine decomposition rates; first order kinetics was found in all cases.
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2.
A convenient method has been developed for the synthesis of 5-methyl-2-desoxyuridines. Chlorination of 5-O-benzoyl-5-methyluridines with a mixture of Ph3P and CCl4 in DMF affords the 2-desoxy-2-chloro-derivatives, which are then reduced with tributyltin hydride. The crystalline 5-O-benzoyl-5-methyl-2-desoxyuridines were obtained in overall yields of 40–60%. In a similar way, 5-O-benzoyluridine has given 5-O-benzoyl-2-desoxyuridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 246–248, February, 1989.  相似文献   

3.
Summary The dynamic mechanical properties of nylon 66 films and fibers have been examined, as a function of annealing and drawing, with a Vibron viscoelastometer. It is found that the transition is little affected by annealing treatments, but increase in orientation causes the transition to move to a higher temperature. Experiments, with X-ray diffraction of samples at elevated temperatures, lead to the conclusion that the triclinic to hexagonal phase change does not contribute significantly to the transition. Samples cut parallel and perpendicular to the drawing direction of nylon 66 film, have been used to show that the curves of dynamic tensile modulus versus temperature, for the parallel and perpendicular directions, cross in the neighborhood of the transition. This observation is discussed in relation to the suggestion that the transition is the glass transition in nylon 66.
Zusammenfassung Die dynamisch-mechanischen Eigenschaften von Filmen und Fasern aus Nylon 66 wurden als Funktion der Temperung und Verstreckung mit einem Virbon-Viskoelastometer untersucht. Die -Umwandlung wird wenig durch die Temperung beeinflußt, aber erhöhte Orientierung läßt siezu höheren Temperaturen verlagern. Messungen der Röntgenstreuung bei erhöhten Temperaturen führen zu dem Schluß, daß der Übergang triklin/hexagonal nicht wesentlich zu der -Umwandlung beiträgt. Proben aus verstrecktem Nylon-66-Film, parallel und senkrecht zur Streckrichtung geschnitten, zeigen, daß die Kurven des dynamischenE-Moduls gegen die Temperatur für beide Orientierungen sich in der Nachbarschaft der -Umwandlung überkreuzen. Diese Beobachtung wird hinsichtlich der Vermutung diskutiert, daß die -Umwandlung den Glasübergang in Nylon 66 darstellt.


With 5 figures and 2 tables  相似文献   

4.
The electronic structure of the configurational isomers of 3-3-, 3-5- and 5-5-bis-oxadiazole, and of trans-,-di-(3-3)-, -(3-5)- and -(5-5)-diazolyl-ethylene, was studied by using the ASMO, SCF, CI procedure developed by Pariser, Parr and Pople. The total -electron energy is taken as the measure for ranging the various isomers and their different configurations in a given order of stability.Predictions based on charge distributions and bond orders are in agreement with the chemical behaviour of the known 3-3 and 5-5 isomers, and are therefore regarded as reliable also for the 3-5 compounds, not described in the literature so far.The calculated value of the lowest singlet transition energy agrees with the observed spectra, with a scatter of ±0.20 eV depending on the particular procedure chosen for calculating the pqand (App) integrals. The calculated second singlet transition is found to depend on the procedure chosen for those integrals to such an extent as to make the prediction unreliable.
Zusammenfassung Die Elektronenstruktur der Konfigurationsisomere von 3,3-, 3,5- und 5,5-bis-Oxadiazol und trans-,-di-3,3-, -3,5- und -5,5-Diazolyläthylen wurde mit Hilfe der ASMO-SCF-CI-Methode studiert. Die totale -Elektronenenergie wurde als Maß für die Stabilität der verschiedenen Isomere und ihrer Konfigurationen gewählt.Voraussagen, die auf Ladungsverteilungen und Bindungsordnungen basieren, sind in Übereinstimmung mit dem chemischen Verhalten der bekannten 3,3- und 5,5-Isomere und wurden deshalb auch als zuverlässig für die 3,5-Verbindungen angesehen, die bis jetzt in der Literatur nicht beschrieben sind.Der berechnete Wert für die niedrigste Singulett-Anregungsenergie stimmt mit den beobachteten Spektren bis auf ±0,2 eV überein, abhängig von der Berechnungsart für die pqund (App). Die Anregungsenergie für den zweiten Singulettübergang läßt sich in diesem Rahmen nicht vorhersagen.

Résumé La structure électronique des isomères configurationales des 3-3-, 3-5- et 5-5-bis-oxadiazole, et des trans---di-(3-3)-, -(3-5)- et -(5-5)-diazolyl-ethylène a été étudiée par la méthode ASMO, SCF, CI sélon la forme développée par Pariser, Parr et Pople. L'énergie totale des électrons a été prise comme étalon pour classifier les isomères et leurs differentes configurations sélon un ordre de stabilité.Les déductions que l'on peut tirer de la distribution des charges et des ordres de liaison sont en accord avec les observations chimiques des isomères connus, 3-3 et 5-5; par conséquent on peut considérer raisonables les prédictions que ont été faites sur les isomères 3-5, qui ne sont pas décrites dans la literature jusqu'ici.La valeur calculée pour la première transition de singulet est en bon accord avec le spectre d'absorption observé, l'incertitude due à la procedure choisie pour les integrales pqet (App) étant ±0.20 eV. La deuxième transition de singulet apparait dépendre presque entièrement de la choix faite pour les dites integrales.
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5.
Acetovanillon and the known flavonoids irisolidone, irigenin, irisolone, tectorigenin and dihydroquercetin-7.3-dimethylether were detected in the rhizomes of Iris germanica. Also a few unknown compounds could be isolated and their structure elucidated; 9-methoxy-7-(3.4.5-trimethoxyphenyl)-8H-1.3-dioxolo[4.5-g] [1]-benzopyran-8-on (=5.3.4.5-tetramethoxy-6.7-methylenedioxyisoflavone (III A); 9-methoxy-7-(3.4-dimethoxyphenyl)-8H-1.3-dioxolo[4.5-g] [1]-benzopyran-8-on (=5.3.4-trimethoxy-6.7-methylenedioxyisoflavone(III B); 9-hydroxy-7-(p-hydroxyphenyl)-8H-1.3-dioxolo[4.5-g] [1]-benzopyran-8-on (=5.4-dihydroxy-6.7-methylenedioxyiosoflavone (IX); 5.7-dihydroxy-3-(3-hydroxy-4-methoxyphenyl)-6-methoxy-4H-1-benzopyran-4-on (=5.7.3-trihydroxy-6.4-dimethoxyisoflavone (XI B); 5.7-dihydroxy-3-(4-hydroxy-3-methoxyphenyl)-6-methoxy-4H-1-benzopyran-4-on (=5.7.4-trihydroxy-6.3-dimethoxyisoflavone (XI C).The structure determination was effected by combined spectroscopical and chemical methods.

Herrn Prof. Dr.F. Hecht mit den besten Wünschen zum 70. Geburtstag gewidmet.  相似文献   

6.
Zusammenfassung Es wird über die Reaktion verschieden methylsubstituierter 4-Hydroxychalkone mittels Chinonimidchlorid berichtet und gezeigt, daß die Ausbeute an 2,6-Dimethylphenol-indophenol bei der Spaltung von 4,4-Dihydroxy-3,5,3-trimethylchalkon (VII) am RingB dreimal so groß ist als beim 4,4-Dihydroxy-3,3,5-trimethylchalkon (III) am RingA.
The reaction between several methyl-4-hydroxy-chalkones and p-benzoquinone-monochloroimine has been studied. It has been shown that the yield of 2.6-dimethylphenol-indophenol from the cleavage of 4.4-dihydroxy-3.5.3-trimethyl-chalkon (VII) at ringB is three times the yield resulting from the cleavage of 4.4-dihydroxy-3.3.5-trimethylchalkon (III) at ringA.


Herrn Prof. Dr.H. Bretschneider zum 60. Geburtstag gewidmet.  相似文献   

7.
Summary 7-(3,3-Dimethylallyloxy)-6-methoxycoumarin and two new coumarins — ramosin and ramosinin — have been isolated from the epigeal part ofHaplophyllum ramosissimum.On the basis of IR, PMR, and mass spectroscopy and chemical reactions, the structure of 8-(3,3-dimethylallyl)-7-(3,3-dimethylallyloxy)coumarin (II) has been proposed for ramosin and that of 3-(1,1-dimethylallyl)-8-(3,3-dimethylallyl)-7-methoxycoumarin (III) for ramosinin.Leningrad Sanitary-Hygienic Medical Institute. Institute of Chemistry, Academy of Sciences of the Turkmen SSR, Ashkhabad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 15–17, January–February, 1979.  相似文献   

8.
Summary In the bromination of 3,5-dialkyl-4-ethylphenols in aqueous acetic acid: at 0° p-quinobromides are formed; and at 40° the corresponding 3,5-dialkyl-4-hydroxyacetophenones are formed.The acetylation of sterically hindered 2,6-dialkylphenols leads to the formation of 3, 5-dialkyl-4-hydroxy-acetophenones in high yield.The author thanks N. M. Émanuél for his constant interest to the work.  相似文献   

9.
Several N-substituted 3-phthalimidopiperidine-2,6-diones and 3-(3phthalimido-2,5-dioxopyrrolid-1-yl)piperidine-2,6-dione have been synthesized.  相似文献   

10.
Zusammenfassung Cyclohexanon bzw. Cyclopentanon sowie ihre durch Aldolreaktion entstehenden Dimeren reagieren mit Harnstoff im sauren Medium zu 5,6,7,8-Tetrahydrospiro[cyclohexan-1,4(1H)-chinazolin]-3(2H)-onen (2) bzw. zum Dihydrospiro-(cyclopentan-1,4(1H)-5H-cyclopenta[d]pyrimidin)-2(3H)-on (10). Substituierte Harnsotoffe geben Gemische der isomeren 5,6,7,8-Tetrahydro- und 4a,5,6,7-Tetrahydroverbindungen (2, 3) bzw. 6,7-Dihydro-tH- und 5,6-Dihydro-4aH-verbindungen (10, 11). Charakteristisch für2 (3),10 (11) ist die Reaktivität der Kernstellen 8 bzw. 7 gegenüber elektrophilen Agentien (2f-v, 3f-j, 9 a-i, 10 d-f). Äthylmalonsäurebis-trichlorphenylester bzw. Formaldehyd und prim. Amine führen2 in ein partiell hydriertes 1H-Pyrido[3,2,1-ij]chinazolintrion (6) bzw. 1H-Pyrimido[5,6,1-ij]chinazolinon (7) über. Die 1-Alkylverbindungen (2) geben mit Formaldehyd und primären Aminen Hexahydro-8a-hydroxy-4a,8-propanospiro-(cyclohexan-1,4(1H)-pyrido[4,3-d]pyrimidin)-2(3H)-one (8).
Heterocycles, XXV: tetrahydrospiro [cyclohexane-1,4(1H)-quinazoline]-2(3H)-ones
Cyclohexanone and cyclopentanone, resp., as well as their dimers (formed by aldol reaction) react with urea in the presence of acids to 5,6,7,8-tetrahydrospiro[cyclohexane-1,4-(1H)-quinazoline]-3(2H)-ones (2) and to the dihydrospiro-(cyclopentane-1,4(2H)-5H-cyclopenta[d]pyrimidine)-2(3H)-one (10), resp. Substituted ureas give the isomeric 5,6,7,8-tetrahydro- and 4a,5,6,7-tetrahydro compounds (2, 3), and 6,7-dihydro-5H- and 5,6-dihydro-4aH-compounds (10, 11), resp. Characteristic for2 (3),10 (11) is the reactivity of the nuclear places 8 and 7 with electrophilic agents (2f-v, 3f-j, 9a-i, 10d-f). Ethylmalonic acid bistrichlorophenylester resp. formaldehyde and primary amines react with2 to the partially-hydrogenated 1H-pyrido[3,2,1-ij]-quinazolinetrione (6) and 1H-pyrimido[5,6,1-ij]-quinazolinone (7), resp. The 1-alkyl compounds (2) give with formaldehyde and primary amines hexahydro-8a-hydroxy-4a, 8-propanospiro(cyclohexane-1,4-(1H)-pyrido[4,3-d]pyrimidine)-2(3H)-ones (8).
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11.
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1].  相似文献   

12.
1,2,5-Trimethyl-4-(9-fluorenylidene)piperidine, which is formed by condensation of fluorene with 1,2,5-trimethyl-4-piperidone, is converted catalytically to 9(2,5-dimethyl-4-pyridyl)fluorene, from which 2-methylpyrido[4,5-a]fluoranthene and its demethylated analog were obtained by catalytic dehydrocyclization. Oxidation of 9-(2,5-dimethy1-4-pyridyl)fluorene gave 9-(2,5-dimethyl-4-pyridyl)9-fluorenol and fluorene-9-spiro-4-(6-oxo-2-carboxypyrido[4,5-c]-4-6-dihydrofuran). 6-Methyl-2-phenyl-7-(9-fluorenyl)indolizine was synthesized by the Chichibabin method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1090, August, 1978.  相似文献   

13.
It has been shown that the reaction of monomethinecyanines containing 4-benzopyrylium residues with quaternary salts of derivatives of 2-[(1, 5, 5-trimethylcyclohex-1-en-3-ylidene)-methyl]benzothiazole leads to the scission of the pyrylium ring and the addition of the quaternary salt to the position of scission. The reaction gives tetracarbocyanines containing an o-hydroxyphenyl or an o-acetoxyphenyl substituent in the polymethine chain in addition to a hydrocarbon ring.  相似文献   

14.
By the condensation of -halogenomethyl derivatives of pyrroles with -unsubstituted pyrroles the synthesis of the following unsymmetrical dipyrrolylmethanes has been effected: 5-benzyloxycarbonyl-5-ethoxycarbonyl-3, 3-di(-methoxycarbonylethyl)-4,4-dimethyl-2,2-dipyrrolylmethane (IIIa), 5-benzyloxycarbonyl-5-ethoxycarbonyl-3-(-methoxycarbonylethyl)-4, 4-diniethyl-3-n-propyl-2,2-dipyrrolylmethane(IIIb), 3-acetyl-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIIc), and 3-bromo-5-benzyloxycarbonyl-4-ethyl-5-methoxycarbonyl-3, 4-dimethyl-2,2-dipyrrolylmethane (IIId). Hydrogenation of the unsymmetrical dipyrrolylmethanes IIIa, b, c, and d has given the corresponding monocarboxylic acids IVa, b, c, and d. The formylation of the dipyrrolylmethanemonocarboxylic acid IVa has given 5-ethoxycarbonyl-5-formyl-3,3-di(-methoxycarbonylethyl)-4, 4-dimethyl-2,2-dipyrrolylmethane (V).For communication II, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp. 1045–1047, August, 1970.  相似文献   

15.
The electron and geometric structures of the cis and trans isomers of 3,3,4,4-tetrachloroazobenzene (3,3,4,4-TCAB) and the trans isomers of 3,3,5,5-TCAB and 3,3-dichloro-4,4-difluoroazobenzene were calculated by the MNDO method. It was established that the trans isomer, which has a planar structure, is most stable for 3,3,4,4-TCAB. Change in the position of the Cl atoms in the azobenzene, i.e., the transition from 3,3,4,4-TCAB to 3,3,5,5-TCAB, does not lead to appreciable change in the formation energy, the position of the electronic levels, the nature of the frontier orbitals, or the charge distribution in the molecules. This gives reason to suggest that the biological activity of 3,3,4,4-TCAB is due to the metabolism products and not to the action of the substrates themselves.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1797–1801, August, 1990.  相似文献   

16.
The results of X-ray crystallographic investigations of compounds containing a 2,2-bithienyl fragment are summarized and analyzed. The structural characteristics of unsubstituted bithiophene, 5-monosubstituted, 5,5-, 3,3-, 4,4-, and 3,4-disubstituted, and more highly substituted bithiophenes and also the structure of -conjugated oligothiophene derivatives are considered.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–760, June, 2000.  相似文献   

17.
3,4,3,4-Tetramethyldiphenyl ether readily forms 2,2-dihalo derivatives on bromination and iodination. Heating 2,2-diiodo-4,5,4,5-tetramethyldiphenyl ether with copper powder or oxidation, of 2,2-dilithio-4,5,4,5-tetramethyldiphenyl ether gives 2,3,7,8-tetramethyldibenzofuran, the structure of which was proved by alternative synthesis from 2,2-dinitroand 2,2-diamino-4,5,4,5-tetramethyldiphenyls.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1597–1599, December, 1972.  相似文献   

18.
New tricylic heterocyclic systems and their methyl derivatives are synthesized. They are 2-methylimidazo[5, 4-e]benzo-1, 2, 3-thiadiazole, 2-methylimidazo[5, 4-g]benzo-1, 2', 3-thiadiazole, 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole, and 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole. Quaternary salts of the 1, 2-dimethyl derivatives are used to prepare symmetrical and unsymmetrical trimethinecyanines and dimethinemerocyanines containing rhodanine groups. The absorption maxima of the dyes are displaced towards the long wavelength region compared with imidacarbocyanines. It is shown that when 1, 2-dimetnyl-5-aminobenzoimidazole is thiocyanated, the thiocyano group enters the benzoimidazole ring at position 4, and that 1, 2-dimethylimidazo[5, 4-e] benzo-1, 2, 3-thiadiazole is less basic than its isomer 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole.  相似文献   

19.
Zusammenfassung Das beim Erhitzen von Cyclohexanon und Harnstoff entstehende Produkt ist nicht als Cyclohexyliden-2-carbamylcyclohex-1-enylamin, sondern als 5, 6, 7, 8-Tetrahydrospiro-[cyclohexan-1,2(1H)-chinazolin]-4(3H)-on zu formulieren1. Analog gebaute Verbindungen bilden sich aus Cyclopentanon bzw. Cycloheptanon und Harnstoff. Die genannten Kondensate sind als cyclische -Carbamylenamine aufzufassen; charakteristisch sind die Reaktivität der zur NH-Gruppe/1, in peri-Stellung befindlichen CH2-Gruppe bzw. der Kernstelle 4a.
-Carbamoyl enamines: 5. 6. 7. 8-Yetrahydrospiro [cyclohexane-1,2 (1H)-quinazoline]-4 (3H)-one. (Heterocycles, XXIII)
The product obtained by heating cyclohexanone with urea has been found to be 5. 6. 7. 8-tetrahydrospiro[cyclohexane-1.2(1H)-quinazoline]-4(3H)-one, not cyclohexylidene-2-carbamoylcyclohex-1-enylamine, as was previously assumed1. Compounds with analogous structures were formed by heating cyclopentanone or cycloheptanone with urea. Characteristic features of this class of compounds, i.e. -carbamoyl enamines, are the enhanced reactivities of the nuclear 4 a-position and of the methylene group in the peri-position to NH-1.
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20.
Conclusions 1. Xanthalin has been shown to have the structure of 2, 2-dimethyl-3, 4,-diangeloyloxy-3, 4-dihydropyrano-5, 6:6, 7-coumarin on the basis of the preparation of a number of derivatives and cleavage products.2. The following products of the alkaline hydrolysis of xanthalin have been isolated and characterized for the first time: (±)-3, 4-dihydroxy-3, 4-dihydroxanthyletin (isokhellactone), C14H14O5, with mp 213–215° C and (–)-trans-3-hydroxy-4-methoxy-3, 4-dihydroxanthyletin (isomethylkhellactone, C15H16O5, with mp 136.5–138° C and [] D 20 –47.7 (ethanol).Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 14–19, 1970  相似文献   

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