Pyrene 3-aldehyde

The first finished procedure was a report in a classical paper on pyrene by an I. G. Farbenindustrie group on the preparation of pyrene-3-aldehyde. N-Methyl-formanilide (135 g.) was mixed with 100 ml. of o-dichlorobenzene (to promote... 

The relative energies of the excited states may be such that intersystem crossing may not be favorable. For example, 3- and 4-pyrene-aldehyde, 2-naphthaldehyde, 9-anthraldehyde, 3-acenaphthaldehyde,... 

The results reported here and in earlier publications in this series suggest that cavity size and limitations to molecular motion play a dominant role in the photochemistry and photophysics of alkyl aryl ketones included in zeolites. In the case of Silicalite the size and polarity of various substituted 8-phenylpropiophenones seem to determine the efficiency of inclusion and ultimately of luminescence. The same factors, relating to size and mobility can be expected to play an important role in the use of zeolites as catalysts for other reactions, whether these are photochemical or thermal processes. In this sense studies with 8-phenylpropiophenones may lead to considerable information on adsorption sites and on the freedom (or lack of it) of molecular motion as well as on the accessibility of these sites to other reactants. Recent work from Turro s laboratory has shown that pyrene aldehyde can be used to probe the nature of inclusion sites in various zeolites (27) dibenzyl-ketones were also used as probes on porous silica (28). 

The above picture is reinforced by results obtained from a related technique. During the last 20 years the use of fluorescent probes to study micellization and aggregation phenomena has become widespread, because of the sensitivity and simphcity of the basic method. In essence, this method is based on the fact that selected fluorescence probes, e.g., pyrene, pyrene aldehyde, and so forth, exhibit different fluorescence characteristics in aqueous ( polar ) and nonaqueous ( nonpolar ) environments (33). Probes are generally (but not always) chosen that are sparingly soluble in water so that if aggregates of surfactant form they will tend to distribute toward the latter and the overall fluorescence characteristics of the solution will change (34,35). Typically, measured fluorescence characteristics will be of the form shown in Figure 9. 

For example, in the case of pyrene (the most widely used fluorescent dye) the measured parameter is /1//3, the ratio of intensity of the first (372 nm) and third (385 nm) fluorescence peaks for pyrene aldehyde it is the wavelength of maximum absorption (36,37). In the presence of interacting polymer the plot is displaced to lower surfactant concentration this implies that a surfactant aggregation process, formally akin to micelli-... 

Investigation of the gelatin-SDS system by Greener et al. (see above) included fluorescence measurements in which pyrene aldehyde was the probe. The characteristic sigmoidal response referred to earlier (Fig. 9) was obtained, but the fluorescence data also showed that ... 

Pyrene-1-aldehyde [3029-19-4] M 230.3, m 125-126 . Recrystd three times from aqueous EtOH. 

Herner HA, JE Trosko, SJ Masten (2001) The epigenic toxicity of pyrene and related ozonation byproducts containing an aldehyde functional group. Environ Sci Technol 35 3576-3583. 

Figure 15.15 An aldehyde derivative of pyrene can be used to couple a hydrophilic amino-PEG-carboxylate spacer by reductive amination. The resultant derivative then can be used to coat a carbon nanotube through pyrene ring adsorption and result in a water-soluble derivative containing terminal carboxylates for coupling amine-containing ligands.

This aldehyde synthesis is applicable to compounds of the aromatic series having a labile hydrogen atom (phenyl ethers,1 naphthols,2 dialkylanilines,3-4 naphthostyril,2 anthrones 2) and to certain hydrocarbons of requisite reactivity (anthracene,5-6 7 1,2-benzanthracene,6 3,4-benzpyrene,3 7 pyrene,8 styrene,9 and a, a-diarylethylenes 9). With polynuclear hydrocarbons the best results are secured by the use of a solvent such as o-dichloro-benzene. 9-Anthraldehyde has also been prepared by the action of hydrogen cyanide and aluminum chloride on anthracene in chlorobenzene.10... 

Pyridylamine, see 2-Aminopyridine a-Pyridylamine, see 2-Aminopyridine p-Pyrine, see Pyrene Pyrinex, see Chlorpyrifos Pyroacetic acid, see Acetone Pyroacetic ether, see Acetone Pyrobenzol, see Benzene Pyrobenzole, see Benzene Pyrofax, see Butane Pyroligneous acid, see Acetic acid Pyromucic aldehyde, see Furfural Pyropentylene, see Cyclopentadiene Pyrophosphoric acid, tetraethyl ester, see Tetraethyl pyrophosphate... 

Figure 2. Unconvoluted anisotropy decays of 1-pyrene car ox-aldehyde in sulfonate micelles (a) sulfonate A (5 x 10 M)/ heptane (7 ns), (b) Sulfonate B (5 x 10 M /heptane (28 ns). The cmc of sulfonate A is less than 10 °M, while that of sulfonate B is "infinitely" dilute.

Diamino-2,l>3-benzothiadiazole 201 undergoes cyclization on reaction with selected aromatic aldehydes <2004T2953>. Thus, reactions with pyrene-l-carboxaldehyde or naphthalene-1-carboxaldehyde in refluxing toluene produce the corresponding imidazoles 202 in moderate yields, whereas reactions with /i-(Ar,Ar-dimethylamino)benz-aldehyde and /i-[Ar,Ar-di(4-methylphenyl)amino]benzaldehyde under similar conditions gave the corresponding 5-imino derivatives 203 (Scheme 13). 

To keep the probe specifically at the primary amine side chains, we have used pyrenecarboxaldehyde and attached it covalently to polyethylenimine by reduction with sodium borohydride of the Schiff base formed between the probe aldehyde and the polymer primary amine. Such reductive alkylation has been used widely with primary amines of enzymes.43,44 For three different adducts to the polymer, the extent of coupling with pyrene, expressed relative to units of monomer residues,... 

Many polycyclic aromatic amines and aldehydes are commercially available, but their supply is very limited. Preparation of these starting materials is necessary for studying the (3-lactam formation reaction [93]. Nitro compounds are the precursors for the amines. An important task was to prepare polycyclic aromatic nitro compounds, particularly those of chrysene, phenanthrene, pyrene, and dibenzofluorene in good yield. Nitration of these hydrocarbons with concentrated nitric acid in sulfuric acid is a widely used reaction for this purpose. Our research culminated in facile synthesis of polyaromatic nitro derivative 9 starting from polyaromatic hydrocarbons (PAHs) 8 through the use of bismuth nitrate impregnated with clay (Scheme 1) ([94, 95] for some examples of bismuth nitrate-catalyzed reactions... 

In the case of pyrene, there are two sextets and two fixed double bonds similar to the phenanthrenic double bond. In agreement with this argument and with the result for phenanthrene, co-ozonolysis of pyrene with formaldehyde or acetyl cyanide afforded the expected normal ozonide 114 and the cross-ozonide 115 with an aldehydic group. In a separate co-ozonolysis of 115 with vinyl acetate, diozonides 116 were prepared. No cross-ozonide was obtained in the presence of benzoyl cyanide, which afforded only the normal mono-ozonide 114 (Scheme 36 and Table 15). 

Under the Schmidt reaction conditions, the lactol (152) of 4-formyl-5-phenanthroic acid gives 1 -aza-pyren-2(lW)-one (153) and phenathrene-4,5-dicarboximide (154)." The compound (153) may be formed by attack of hydrazoic acid at the latent aldehyde site in preference to the carboxy site (see Section 4.4.4.2). Phenanthrene-4,5-dicarboxylic acid (155), obtained by oxidation of (152), similarly affords... 

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