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Benzophenone, preparation solubility

Iodoform reaction. To 0 5 ml. of acetone add 3 ml. of 10% KI solution and 10 ml. of freshly prepared sodium hypochlorite solution and mix well. A pale yellow precipitate of iodofonn is rapidly formed without heating. Acetophenone similarly gives iodoform, but the mixture must be shaken vigorously on account of the limited solubility of acetophenone in water. Benzophenone does not give iodoform. [Pg.346]

Poly(phenylquinoxaline—arnide—imides) are thermally stable up to 430°C and are soluble in polar organic solvents (17). Transparent films of these materials exhibit electrical insulating properties. Quinoxaline—imide copolymer films prepared by polycondensation of 6,6 -meth5lene bis(2-methyl-3,l-benzoxazine-4-one) and 3,3, 4,4 -benzophenone tetracarboxyUc dianhydride and 4,4 -oxydianiline exhibit good chemical etching properties (18). The polymers are soluble, but stable only up to 200—300°C. [Pg.532]

Two polymers have been prepared with the benzophenone tetracarboxylic dianhydride (BTDA) and either bis-l,3-(4-aminophenoxy)-benzene or bis-l,3-(4-aminophenoxy)-2-cyano-benzene (Fig. 5.6). Both polymers are soluble in NMP and their Tg values are respectively 191 and 243°C.59... [Pg.276]

Preparative photolysis of AETSAPPE (0.25 M aqueous solution) at 254 nm (Rayonet reactor) resulted in the formation of the disulfide product 2-amino(2-hydroxy-3-(phenyl ether) propyl) ether disulfide (AHPEPED) as the primary photoproduct Photolysis of AETSAPPE at 254 nm (isolated line of medium pressure mercury lamp) resulted in rapid initial loss of starting material accompanied by formation (analyzed by HPLC) of AHPEPED (Figure 12a and 12b) (Scheme IV). Similar results were obtained for photolysis- at 280 nm. Quantum yields for disappearance of AETSAPPE and formation of AHPEPED at 254 nm and 280 nm are given in Table I. The photolytic decomposition of AETSAPPE in water was also accomplished by sensitization ( x =366 nm) with (4-benzoylbenzyl) trimethylammonium chloride (BTC), a water soluble benzophenone type triplet sensitizer. The quantum yield for the sensitized disappearance (Table I) is comparable to the results for direct photolysis (unfortunately, due to experimental complications we did not measure the quantum yield for AHPEPED formation). These results indicate that direct photolysis of AETSAPPE probably proceeds from a triplet state. [Pg.296]

Fully imidized soluble polyimides have ben prepared using monomers derived from diphenylindane and aromatic dianhydrides. Technical polymers (XU218, for instance), prepared from 1,1,3-trimethyl-diaminophenylindane and benzophenone-tetracarboxylic acid dianhydride, have been marketed over the last decade. Despite the partially aliphatic nature of polyimides containing the indane group, they show considerable retention of the thermal stability, with Tg values over 300 °C [107-110]. [Pg.45]

Aromatic blsmalelmldes were much less effective (Table 3), partly because of low solubility In the polystyrene solutions and partly because the rates of photoaddltlon were much lower than those of the aliphatic blsmalelmldes. Not unexpectedly (In view of the results shown In Table 2), the blsmalelmlde prepared from o,o -dlmethylbenzldlne (o-tolldlne) was least effective. Only In the case of 4,4 -blsmalelmldodlphenylsulfone did photosensitizer (benzophenone) noticeably shorten gelation... [Pg.70]

Disodium tetracarbonylferrate (Collman s reagent) is prepared by the reduction of Fe(CO)5 with sodium naphthalene in THF or sodium benzophenone ketyl in dioxane. Though it can be isolated as a white precipitate, it is usually used in THF or dioxane solution without isolation because of its highly air-sensitive and pyrophoric character. It is reported that the solubility of Na2[Fe(CO)4] is 7 x 10 M in THF and that it can be stored for moderate periods in an inert atmosphere in the dark [36]. X-ray crystallography of Na2[Fe(CO)4] (Fig. 10.2) shows that the C—Fe—C bond angle opposite to the sodium cations is significantly distorted (129.7°) [37]. However, this distortion is reduced for the potassium analogue [38]. [Pg.166]

The solubility of PNI based on l,3-bis(l,8-dicarboxynaphthoyl)benzene dianhydride is almost identical to that of PNI prepared from 4,4 -bis(l,8-dicarboxynaphthoxy-4)benzophenone dianhydride. Contrary to the DNTA-based PNI [14], para isomeric... [Pg.35]

Dichloro(l,S-cyclooctadiene)platmum(II) may be prepared from hexa-chloroplatinic acid, or by heating bis(benzonitrile)dichloroplatinum(II) in 1,5-cyclooctadiene at 145°C for 5 min, or from potassium tetra chloroplatinate(2-). The complex [PtCl2(CgHi2)] has a very low solubility in the reaction mixture and must be finely ground to ensure complete reaction. The olefins 1,5-cyclooctadiene, bicyclo[2.2.1]hept-2-ene (2-norbomeneX and 1,3,5,7-cyclooctatetraene and all solvents should be dried and freshly distilled under nitrogen. In particular, peroxide-firee diethyl ether is first dried over sodium wire and then distilled under nitrogen from sodium-benzophenone. [Pg.127]

Liska reported preparation of water-soluble photoinitiators that contain carbohydrate residues as well as copolymerizable derivatives of the carbohydrate residues. These materials consist of alkylphenones, benzophenones and thioxanthones. To these compounds were attached carbohydrates like glucose, cellobiose, and 1-amino-1-deoxy-D-glucitol. In addition selected initiators were reacted with methacryloyl chloride to form polymerizable photoinitiators. The glucose modified photoinitiators were claimed to yield the best results with respect to compatibility with resins, reactivity and gel content. ... [Pg.70]

Two soluble polyimides were synthesized from aromatie diamine monomers eontaining benzophenone moieties, 3,3, 5,5 -tetramethyl-4,4 -diaminodiphenylmethane and 3,3, 5,5 -tetramethyl-4,4 -diamino-diphenyl ketone) and 3,3, 4,4 -benzophenone tetraearboxylie dianhydride. The polymers were reported to be photoerosslinkable and exhibited self-hypersensitizing properties. They preparation ean be illustrated as follows ... [Pg.232]

In addition to aromatic solvents, we have seen reactivity of active uranium prepared in 1-decene and TMEDA. The yields of TPE and TPA resulting from preparation and reaction of active uranium with benzophenone in 1-decene are only slightly lower than those in aromatic solvents, presumably due to solubility considerations. There was little difference in the proportion of TPA to TPE. It appears that decene does not serve as either a hydride source (allylic hydrogens) or a hydride sink (via hydrogenation of the double bond). The preparation and reaction of active uranium with benzophenone in TMEDA gave yields of TPE comparable to other aromatic solvents at that temperature ( 20%). Negligible amounts of TPA were seen, however. The presence of a large excess of a basic solvent could serve to reduce the amount of metal hydrides present. [Pg.417]


See other pages where Benzophenone, preparation solubility is mentioned: [Pg.161]    [Pg.46]    [Pg.193]    [Pg.588]    [Pg.236]    [Pg.83]    [Pg.441]    [Pg.332]    [Pg.459]    [Pg.198]    [Pg.43]    [Pg.302]    [Pg.418]    [Pg.84]    [Pg.49]    [Pg.413]    [Pg.206]    [Pg.336]    [Pg.161]    [Pg.158]    [Pg.158]    [Pg.161]    [Pg.194]    [Pg.1078]    [Pg.9]    [Pg.693]    [Pg.693]    [Pg.108]    [Pg.127]    [Pg.288]    [Pg.24]    [Pg.80]    [Pg.1078]    [Pg.5]    [Pg.35]   
See also in sourсe #XX -- [ Pg.192 ]




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Benzophenone preparation

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