Pyrene, substituted

Energies for various possible arenium ions and regioisomeric benzylic cations were computed at the DFT B3LYP/6-31G(d) level or by AMI for comparison with the experimental results. These findings provided further evidence in support of the stability sequence 1-pyrenyl > 4-pyrenyl > 2-pyrenyl in a-pyrene-substituted carbocations as models for the intermediates arising from BaP-epoxide ring opening (Fig. 10). 

Horner-Wadsworth-Emmons procedures are also commonplace in synthetic materials chemistry, recent examples including donor-acceptor substituted molecules with bicyclo-spacers, which require napthalene-, anthracene-, and pyrene-substituted phosphonates, (112), (113) and (114) respectively, well-defined, electroactive PPE/PPV copolymers through the condensation of dialdehydes and bisphosphonate (115), ° and triphenylamine-substituted PPV. ° ... 

Detailed NMR data are available for a series of regioisomeric oc-pyrene-substituted secondary and tertiary carbocations (Figs 25 and 26)27 as well as for... 

Fig. 25. H NMR data for regioisomeric a-pyrene-substituted secondary and tertiary carbocations (<5 H values for the corresponding neutral pyrenes in parentheses).

Azomethane imines undergo an analogous photoinduced cyclization to give diaziridines. The dihydroisoquinoline derivative (99), for example, is converted on irradiation in cyclohexane or benzene into the diaziridine (100) the transformation is thermally reversible. In contrast, the pyrazolidinone azomethine imines (101) undergo photoreversible conversion into the diaziridines (102), providing in this way a useful reversible photochromic system. The analogous photoisomerization of a pyrene-substituted pyrazolidinone azomethinimine has... 

A pyrene derivative was also used as an anchor to immobilize a ruthenium alkylidene complex onto SWCNTs [94]. The immobilization of the Ru complex was performed by two different paths (1) adsorption of pyrene derivative precursor onto the sidewall of nanotubes by ti-ti interactions, followed by cross-metathesis with the ruthenium alkylidene complex, and (2) adsorption onto the sidewall of SWCNTs of the pyrene-substituted ruthenium alkylidene prepared previously. 

Furthermore, like styrylpyrene (5b), pyrene-substituted imine (12) undergoes mutual isomerization between Z and E isomers via the triplet excited state, and the quantum yield for the Z -> E isomerization increases with Z-isomer concentration by way of the dual mechanism. 

Keyes-Baig C, Duhamel J, Wettig S (2011) Characterization of the behavior of a pyrene substituted Gemini surfactant in water by fluorescence. Langmuir 27 3361-3371... 

Primary candidates for the mutagens (and carcinogens ) responsible for activity in the basic fractions include quinoline, substituted quinolines, alkyl pyridines, acridines, aza-arenes, naphthylamines, and aromatic amines in the neutral fractions, potential hazards may be benzanthracenes, dibenzanthracenes, substituted anthracenes, benzopyrenes, benzofluorenes, pyrene, substituted pyrenes, and chrysenes. 

Almgren, M. Swamp, S. Fluorescence stopped-flow study of the interaction of alkylpyridinium salts and pyrene-substituted fatty acids with lecithin vesicles. Chem. Phys. Lipids 1982,31,13-22. 

Eujihira, M. Nishiyama, K. Hamaguchi, Y Tatsu, Y. Eluorescence microscopic study of change in pyrene cluster size in mixed monolayers of pyrene-substituted and normal fatty acids with chain-length matching. Chem. Lett. 1987, 253-256. 

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