Showing papers on "Fluorene published in 1973"
TL;DR: Fluorene interacts with cytochrome P450 from phenobarbital-pretreated rats by formation of an enzyme-substrate complex and it is concluded that the active oxygen can abstract a proton from CH-acidic compounds.
28 citations
TL;DR: In this article, the relative yields of the cis -and α-neopentallyl isomers apparently depend on the steric bulk as well as the strength of the acid, and the degree of rearrangement observed from a series of ketones also is a function of the size of the ketone.
15 citations
9 citations
Patent•
31 Oct 1973TL;DR: In this paper, a composition of matter characterized by the structural formula: where R1 is hydrogen or methyl and R2, R3 and R4 are hydrogen, halogen or aliphatic groups containing 1 to 4 carbon atoms.
Abstract: Disclosed is a composition of matter characterized by the structural formula: WHEREIN R1 is hydrogen or methyl and R2, R3 and R4 are hydrogen, halogen or aliphatic groups containing 1 to 4 carbon atoms. Also disclosed are vinyl polymers of the above material.
8 citations
Patent•
15 Jun 1973
TL;DR: Bis-basic substituted aromatic polycyclic compounds of the following structure are useful in treating conditions of delayed hypersensitivity: ##SPC1## Wherein [W] represents an aromatic poly-cyclic nucleus selected from fluoranthene, fluorene, fluoren-9-ol, or anthraquinone; as mentioned in this paper represents a straight or branched alkylene chain of from 1 to 6 carbon atoms.
Abstract: Bis-basic substituted aromatic polycyclic compounds of the following structure are useful in treating conditions of delayed hypersensitivity: ##SPC1## Wherein [W] represents an aromatic polycyclic nucleus selected from fluoranthene, fluorene, fluoren-9-ol, fluoren-9-one, dibenzofuran, dibenzothiophene, carbazole, N-(lower)alkyl carbazole, xanthene, xanthone, thioxanthene, phenoxathiin, or anthraquinone; Y represents carbonyloxy, carbonylthio, oxygen, divalent sulfur or carbonyl with the provisos that when Y is carbonyloxy or carbonylthio, [W] is other than thioxanthene, phenoxathiin or anthraquinone, when Y is oxygen or divalent sulfur, [W] is other than thioxanthene or phenoxathiin, and when Y is carbonyl, [W] is other than fluoren-9-ol or anthraquinone; A represents a straight or branched alkylene chain of from 1 to 6 carbon atoms with the proviso that when Y is carbonyloxy or carbonylthio, A contains at least 2 straight chain carbon atoms, that is, an ethylene radical; R represents hydrogen, a straight or branched lower alkyl group of from 1 to 4 carbon atoms, phenyl or benzyl; and pharmaceutically useful acid addition salts.
7 citations
7 citations
TL;DR: The fluore-9-methanol esters of the 5′-phosphates of oligon nucleotides are soluble in organic solvents, and the protected oligonucleotides can be isolated by solvent extraction from the reaction mixture.
Abstract: The fluore-9-methanol esters of the 5′-phosphates of oligonucleotides are soluble in organic solvents, and the protected oligonucleotides can be isolated by solvent extraction from the reaction mixture.
6 citations
TL;DR: In this article, time resolved fluorescence spectroscopy measurements were used to investigate energy transfer in anthracene and tetracene doped fluorene crystals, and the results were consistent with both the recently proposed generalized random walk model for energy transfer and the combined exciton diffusion.
6 citations
TL;DR: The metalation of fluorene by means of the Et2Mg-HMPA system was investigated in this article, and it was demonstrated by the kinetic and NMR studies that the active species of metalation in such a case was not Et 2 Mg but the Et 2Mg−HMPA complex, in which two molecules of HMPA are coordinated to Et 2 mg.
Abstract: The metalation of fluorene by means of the Et2Mg–HMPA system was investigated. The reaction scarcely occurred at all when the mole ratio of HMPA: Et2Mg fell below 1:1, but it proceeded easily when the ratio was over 1:1, and a solvent-separated ion pair of magnesium fluorenide was formed. When the ratio was 2:1, the order of reaction was unity in both fluorene and Et2Mg. It was demonstrated by the kinetic and NMR studies that the active species of metalation in such a case was not Et2Mg but the Et2Mg–HMPA complex, in which two molecules of HMPA are coordinated to Et2Mg.
6 citations
6 citations
Patent•
18 Dec 1973
TL;DR: A silver halide photographic emulsion for direct positives, containing a fluorene compound having at least one nitro group as a substituent, was proposed in this paper.
Abstract: A silver halide photographic emulsion for direct positives, containing a fluorene compound having at least one nitro group as a substituent.
Patent•
15 Jun 1973
TL;DR: In this paper, Bis-basic substituted aromatic polycyclic compounds of the following structure are useful in treating conditions of delayed hypersensitivity were used in the treatment of drug hypersensitivity.
Abstract: WHEREIN (W) represents an aromatic polycyclic nucleus selected from fluoranthene, fluorene, fluoren-9-ol, fluoren-9-one, dibenzofuran, dibenzothiophene, carbazole, xanthene, xanthone, thioxanthene, phenoxathiin, or anthraquinone; Y represents carbonyloxy, carbonylthio, oxygen, divalent sulfur or carbonyl with the provisos that when Y is carbonyloxy or carbonylthio, (W) is other than thioxanthene, phenoxathiin or anthraquinone, when Y is oxygen or divalent sulfur, (W) is other than thioxanthene or phenoxathiin, and when Y is carbonyl, (W) is other than fluoren9-ol or anthraquinone; A represents a straight or branched alkylene chain of from one to six carbon atoms with the proviso that when Y is carbonyloxy or carbonylthio, A contains at least two straight chain carbon atoms, that is, an ethylene radical; and pharmaceutically useful acid addition salts. Bis-basic substituted aromatic polycyclic compounds of the following structure are useful in treating conditions of delayed hypersensitivity:
TL;DR: In this paper, delayed fluorescence measurements of pyrene-d10 doped fluorene crystals have been examined as a function of temperature in order to study the correlation between exciton density and electronic triplet spin lattice relaxation.
TL;DR: In this article, the hydrodynamic properties of solutions of polyimide from the dianhydride of 3,4,3′,4′-tetracarboxydiphenyl oxide and 9,9-bis-(4-aminophenyl)fluorene have been investigated and the parameters of the equations relating [ν] to S0andMw have been determined.
Abstract: The hydrodynamic properties of solutions of a polyimide from the dianhydride of 3,4,3′,4′-tetracarboxydiphenyl oxide and 9,9-bis-(4-aminophenyl)fluorene have been investigated and the parameters of the equations relating [ν] to S0andMw have been determined. It was found that beginning at Mw=400 × 103 the behaviour of the polymer molecules in solution is in accord with the theories of non-free-draining Gaussian coils. The length of the Kuhn segment characterizing the chain rigidity is A = 20–21 A.
TL;DR: In this paper, it was shown that the properties of mixed polyimides are dependent mainly on the chemical structure of the acidic component of the mixture, i.e., their solubility in organic solvents and softening point.
Abstract: Mixed polyimides from the dianhydrides of pyromellitic acid, 3,3′,4,4′-diphenyltetracarboxylic acid, 3,3′,4,4′-tetracarboxydiphenyl oxide and 3,3′,4,4′-benzophenonetetracarboxylic acid, reacted with the following diamines: 9,9-bis(4-aminophenyl)fluorene, 9,9-bis(4-aminophenyl)anthrone, 3,3-bis(4-aminophenyl)phthalide and 4,4′-diaminodiphenyl oxide, have been synthesized and studied. It is shown that in this series of capolyimides their properties (solubility in organic solvents and softening point) are dependent mainly on the chemical structure of the acidic component. It was found that heat treatment of films of mixed polyimides containing 3,3′,4,4′-benzophenonetetracarboxylic acid radicals increases their strength characteristics considerably.
TL;DR: In this article, a mixture of 9, 9dichlorofluorene and each diamine in the mole ratio 2: 1.1 was heated with stirring in chlorobenzene or o-Dichlorobenzenes either in the presence or wifhout zinc chloride to give the corresponding pigment.
Abstract: New pigments were obtained by the condensation of 9, 9-dichlorofluorene with aromatic or heterocyclic diamines.9, 9-Dichloroflorene was prepared by oxidation of fluorene with sodiqm bich ma e followed by chlorination of the oxidation product with phosphorous pentachloride. A mixture of 9, 9dichlorefluorene and each diamine in the mole ratio 2: 1.1 was heated with stirring in chlorobenzene or o-dichlorobenzene either in the presence or wifhout zinc chloride to give the corresponding pigment. The synthesized pigments are considered to have the symmetrical structures in which two mol of fuorene are combined with one mol. of the diamine through azomethine bonds, and show certain characteristic properties depending on the diamines employed. Their color is greenish yellow to brownish yellow except for the pigment derived from m-xyly ene diamine. The substituent effects on their color are found in the pigments derived from benzidines, while the conjugation effects are observed in the pigments derived from diaminoanthraquinones. Their solubility depends on their chemical structures; the pigments derived from P-phenylene diamine, 1, 4-diaminoanthraquinone and benzidines are slightly solub1e in several organic solvents, while those derived from heterocycl ic diamines-C 1, 5- and 2, 6-diaminoanthraquinoneS are praetieally insoluble in most organic solvents.It is noted that the diamihes play a small part on the light. fastness of, the synthesized pigments, because most of the pigments have good fastness except for. the pigpaent derived from 4, 6-diamino-5-nitropyri midine.
TL;DR: The contact ion pairs of the anthracene anion-radicals containing the cations of the alkali metals (Li+, Na+, K+) are more reactive in the reaction with fluorene than are the ion pairs that are separated by a solvent as mentioned in this paper.
Abstract: The contact ion pairs of the anthracene anion-radicals containing the cations of the alkali metals (Li+, Na+, K+) are more reactive in the reaction with fluorene than are the ion pairs that are separated by a solvent.
TL;DR: The metalation of fluorene by means of the Et2Mg-HMPA system was investigated in this paper, and it was demonstrated by the kinetic and NMR studies that the active species of metalation in such a case was not Et 2 Mg but the Et 2Mg−HMPA complex, in which two molecules of HMPA are coordinated to Et 2 mg.
Abstract: The metalation of fluorene by means of the Et2Mg–HMPA system was investigated. The reaction scarcely occurred at all when the mole ratio of HMPA: Et2Mg fell below 1:1, but it proceeded easily when the ratio was over 1:1, and a solvent-separated ion pair of magnesium fluorenide was formed. When the ratio was 2:1, the order of reaction was unity in both fluorene and Et2Mg. It was demonstrated by the kinetic and NMR studies that the active species of metalation in such a case was not Et2Mg but the Et2Mg–HMPA complex, in which two molecules of HMPA are coordinated to Et2Mg.