Showing papers on "Fluorenone published in 1977"
TL;DR: In this article, photoinitiated free radical polymerisations are outlined with reference to the requirements for useful photocurable films and coatings, and details of photoinitiation of methyl methacrylate polymerisation by various amine-fluorenone combinations are presented.
Abstract: General features of photoinitiated free radical polymerisations are outlined with reference to the requirements for useful photocurable films and coatings. Initiation via charge transfer processes, including exciplex formation, is reviewed and details of photoinitiation of methyl methacrylate polymerisation by various amine-fluorenone combinations are presented. Results for polymerisations photoinitiated by small molecule fluorenones and copolymers derived from 2-vinyl fluorenone are compared in an attempt to establish detailed reaction mechanisms.
68 citations
TL;DR: In this paper, the 1H and 13C spectra of fluorene, fluorenone, phenanthrene and their 4-methyl and 4-5-dimethyl derivatives have been examined.
Abstract: The 1H and 13C spectra of fluorene, fluorenone, phenanthrene and their 4-methyl and 4,5-dimethyl derivatives have been examined. To complete the analyses for fluorenone and 4-methylfluorenone, 1H spectra were recorded at 270 MHz. The results from the 1H spectra permitted unequivocal assignments for the protonated aryl carbons by selective proton decoupling. A consistent set of assignments for the quaternary carbons was obtained through consideration of the dominant relaxation processes operative at these centres. This series of compounds was examined to investigate the shielding effects produced by the close approach of methyl groups separated by five bonds for comparison with the contrasting trends found for methyl carbons separated by three and four bonds. The results indicate that the relative orientation of the methyl groups is an extremely critical factor governing their shieldings and those of neighboring centres.
44 citations
Patent•
13 May 1977
TL;DR: The photoinitiators are a mixture of an aromatic carbonyl compound A which is derived from benzophenone, fluorenone, anthraquinone, xanthene, thioxanthone or acridone as discussed by the authors.
Abstract: Photopolymerizable coating compositions contain, as the binder, olefinically unsaturated compounds having a boiling point above 50° C, together with from 0.5 to 15% by weight of photoinitiators, based on the binder. The photoinitiators are a mixture of an aromatic carbonyl compound A, which is a derivative of benzoin or benzil, which has at least one carbon-oxygen single bond in the α-position relative to the carbonyl group, an aromatic carbonyl compound B which is derived from benzophenone, fluorenone, anthraquinone, xanthene, thioxanthone or acridone, and an amine C of the general formula ##STR1## where R', R" and R"' are H, alkyl of 1 to 10 carbon atoms, cycloalkyl of 3 to 10 carbon atoms, aryl, hydroxyalkyl of 1 to 8 carbon atoms or alkoxyalkyl of 2 to 4 carbon atoms, but at most 2 substituents are H and at most 2 substituents are aromatic. These coating compositions may be used for finishing various substrates, as fillers or as printing inks.
26 citations
TL;DR: In this article, the energy and quantum efficiency for fluorenone fluorescence in the crystalline state and in polymeric matrices were measured as a function of external pressure over the range 0 −140 kbar.
Abstract: The energy and the quantum efficiency for fluorenone fluorescence in the crystalline state and in polymeric matrices was measured as a function of external pressure over the range 0–140 kbar. The application of high pressure induces changes in the quantum yield, which ranges from 0.001 at low pressure to a maximum of ∼0.1 at high pressure in hydrocarbon plastics. These results are interpreted as arising from the decrease in the energy of the lowest ππ excited singlet state relative to other relevant states as the external pressure is increased.
12 citations
TL;DR: The dilithium salts PhCR(O-Li+)2, formed by the reaction of organolithium derivatives with lithium carboxylates, are stable in ether heated under reflux for 96 h when R = phenyl, 4-tolyl, or 4- or 2-methoxyphenyl, but decompose to give lithium benzoate and RLi if R = 2,6-dimethoxyl, 2-thienyl, or 2 -furyl as mentioned in this paper.
Abstract: The dilithium salts PhCR(O–Li+)2, formed by the reaction of organolithium derivatives with lithium carboxylates, are stable in ether heated under reflux for 96 h when R = phenyl, 4-tolyl, or 4- or 2-methoxyphenyl, but decompose to give lithium benzoate and RLi when R = 2,6-dimethoxyphenyl, 2-thienyl, or 2-furyl. The dilithium salts react with water to give ketones; efficient methods for the synthesis of several substituted benzophenones, 2-benzoylthiophen, and 2-benzoylfuran are reported.Base-induced cleavage of aromatic ketones is formally the reverse of the above reactions. Fluorenone, 2-chlorobenzophenone, 2,6-dimethoxybenzophenone, and 2-benzoylthiophen are cleaved readily when treated with potassium t-butoxide (10 equiv.) and water (3 equiv.) in ether but are unaffected by the analogous reagent prepared with lithium t-butoxide.
10 citations
TL;DR: In this paper, the ESR and triple-resonance spectra of fluorenone ketyl and biphenylide sodium ion pairs in ethereal solutions were reported, and the temperature dependence of the hyperfine constants and their signs were determined by triple resonance.
6 citations
TL;DR: The iron-sulphur cluster (1) functions as an electron-transfer agent in the reduction of fluorenone with n-butyl-lithium to form bifluoren-9-yl-9,9′-diol and/or fluoren- 9-ol.
Abstract: The iron–sulphur cluster (1) functions as an electron-transfer agent in the reduction of fluorenone with n-butyl-lithium to form bifluoren-9-yl-9,9′-diol and/or fluoren-9-ol.
6 citations
5 citations
5 citations
TL;DR: Fluorenone diaryldithioketal (4) decomposes photochemically into free 9-arylthio fluorenyl radicals which dimerize under formation of 9.9′-bifluorenyl (6).
Abstract: Fluorenone diaryldithioketal (4) decomposes photochemically into free 9-arylthio fluorenyl radicals which dimerize under formation of 9.9′-bifluorenyl (6). The reaction behavior of both 4 and 6 under UV irradiation as well as under electron impact conditions can be compared.
4 citations
Patent•
23 May 1977TL;DR: In this article, the authors presented a polymerization method for electrophotographic imaging members and methods, which can be readily polymerized to polymers suitable for use in electrophotonography imaging.
Abstract: Disclosed are monomers of the formula: ##STR1## WHEREIN R is ##STR2## R' is hydrogen or methyl; R" is alkyl of 1-10 carbon atoms; X and Y are independently selected from the group consisting of NO 2 , halogen, cyano and --CF 3 ; Z is oxygen or dicyanomethylene; a and a' can range from 0-3; and n is 1-10. These monomers can be readily polymerized to polymers suitable for use in electrophotographic imaging members and methods.
Patent•
IBM1
TL;DR: In this article, an image is formed by exposing to a light pattern a plate comprising a substrate and only a single layer of a photoconductive, non-polymeric, film forming, pyrazoline, oxadiazoles or fluorenone organic compound which has a glass transition temperature below 200° C.
Abstract: An image is formed by exposing to a light pattern a plate comprising a substrate and only a single layer of a photoconductive, non-polymeric, film forming, pyrazoline, oxadiazoles or fluorenone organic compound which has a glass transition temperature below 200° C. and which has both a crystalline phase and an amorphous phase, and developing the plate by causing a selective change in phase between the light exposed and non-exposed areas.
TL;DR: In this article, 2-nitrofluorenone was obtained as the only product using cupric nitrate in the presence of acetic acid and acetic anhydride.
Abstract: Fluorenone was nitrated using cupric nitrate in the presence of acetic acid and acetic anhydride. Nitration was carried out under mild conditions; 2-nitrofluorenone was obtained as the only product.