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Naphthalene trimers

Scheme IV, the loss of one H atom from the naphthalene trimer leads to a molecule containing a 19-carbon conjugated system and a single sp3 carbon atom. The free radical is stabilized by delocalization of the unpaired electron over the 19-carbon atom network. Loss of an additional H atom results in a fully condensed aromatic hydrocarbon containing 20 carbon atoms. Scheme IV, the loss of one H atom from the naphthalene trimer leads to a molecule containing a 19-carbon conjugated system and a single sp3 carbon atom. The free radical is stabilized by delocalization of the unpaired electron over the 19-carbon atom network. Loss of an additional H atom results in a fully condensed aromatic hydrocarbon containing 20 carbon atoms.
Kim, W., Schaeffer, M.W., Lee, S., Chung, J.S., and Felker, P.M. (1999) Intermolecular vibrations of naphthalene trimer by ionization-detected stimulated Raman spectroscopy. J. Chem. Phys.,... [Pg.193]

In a study by Sato et al. [62], the primaries dissolved in the melted PS or the solvent where the low mass transfer rate lead to significant secondary products. Ohtani et al. [61] avoided secondary products by employing hehum carrier. They reported monomer, dimer, and trimer of styrene. Flash pyrolysis of PS in a fluidized bed under atmospheric conditions rendered liquid products, mainly containing styrene monomer, toluene, ethyl benzene, and naphthalene [33]. [Pg.618]

The nx)st imponam ring system of organic chemistry is (he benzene nng. either as a separate entity or in polynuclear hydrocarbons such as naphthalene, anthracene, and phenanthrene. Inorganic chemistry has two (at (east) analogues ofbenzene borazincs. and trimeric cyclophosphazene compounds. [Pg.918]

The 1,2- and 1,4-addition reactions have been observed also for alkyl-substituted aromatics, but the yields are often low, in particular for benzene derivatives, owing to competing side-chain substitution reactions. Examples include the addition of MeOH to methyl-substituted benzenes [38-42], naphthalenes [43], and anthracenes [43,44]. In a similar fashion, the anodic oxidation of 1,3-dienes in MeOH [45,46] results in mixtures of 1,2- and 1,4-addition products accompanied by substitution products and methoxy-containing dimers and trimers [46]. Styrenes are oxidized in MeOH to the 1,2-addition product together with products formed by dimerization-addition [47,48]. Oxidation of allenes results in most cases in complicated product mixtures resulting from single and double addition reactions [49-52]. [Pg.476]

Jew and Park have also utilized the dimerization effect, as observed in the development of Sharpless asymmetric dihydroxylation, where ligands with two independent cinchona alkaloid units attached to heterocyclic spacers led to a considerable increase in both the enantioselectivity and scope of the substrates, to design dimeric and trimeric cinchona alkaloid-derived phase-transfer catalysts 12 [12] and 13 [13]. These authors investigated the ideal aromatic spacer for optimal dimeric catalysts, and found that the catalyst 14 with a 2,7-bis(bromomethyl) naphthalene spacer and two cinchona alkaloid units exhibited remarkable catalytic and chiral efficiency (Scheme 11.3) [14]. [Pg.386]

As in perchlorophenylacetylene, the initial step is the formation of an open-chain diradicaloid species. The formation of the products is accounted for in a straightforward fashion by the intermediacy of the cisoid and the transoid conformations of the diradicaloid structure, which by cyclization would yield the naphthalene and the fulvene respectively. Note that in perchlorophenylacetylene the transoid species should be inactive. Because of extreme overcrowding, no trimers are formed here. [Pg.344]

CyD dimers and trimers have been developed to improve the binding ability for specific applications. Although the dimer linked with a short alkyl chain 1 showed higher affinity for ditopic guest molecules like p-toluidino-6-naphthalene sulfonate... [Pg.41]

Instructions for the conversion of polynuclear arenes (coronene, anthracene, decacyclene, naphthacene, naphthalene, pentacene, ovalene, 9,10-benzphenanthrene, 1,2-benzanthracene, 1,3,6,8-tetraphenylpyrene) into the corresponding perfluoro-alicyclic compounds and of 1,4-dichlorobenzene into perfluorocyclohexane by LaMar controlled-concentration direct-flow fluorination at room temperature and atmospheric pressure are now available in the patent literature, and precise details of the use of the method, in conjunction with a cryogenic reactor, to convert neopentane into perfluoroneopentane in low yield (10% after g.l.c. isolation) are also to hand. jhe results of kinetic studies on the direct fluorination of methane, [ H2]methane, halogenomethanes, and olefins are likewise in print. Treatment of the perfluoropropene dimers (CFsjsCiCF-CFs-CFs and trans-(CF3)2CF-CF -CF CFa with fluorine at —78 °C yields perfluoro-(2-methylpentane) quantitatively, while fluorination of a mixture of the trimers [(CFsjaCFlaC .CF-CFs and... [Pg.3]

Haneline. M.R. Tsunoda. M. Gabbai, F.P. tt-Complexa-tion of biphenyl, naphthalene, and triphenylene to trimeric perfluoro-orr/io-phenylene mercury. Formation of extended binary stacks with unusual luminescent properties. J. Am. Chem. Soc. 2002. 124. 3737-3742. [Pg.75]

Furan isocyanates FI, MFI, FMI and MFMI were found to give mixtures of polymers (Scheme 6.16) and cyclic trimers (Scheme 6.17) when activated with classical anionic initiators like nBuLi and sodium naphthalene. [Pg.126]

Trifluoromethylphosphinic acid is dimeric (13.2a), while the corresponding chloro compound exists as a cyclic trimer (13.2b). Phenylphosphinic acid, Ph(H)P(0)0H, is trimeric in naphthalene, and some phosphonic acids RP(OH)2 are hexameric whereas phosphinic acids of type RjPlOlOH are dimeric. The esters (RO)PO(OH)2 and (RO)2PO(OH) (R = 2-ethylhexyl or n-octyl) are, according to molecular weight data, extensively polymeric and dimeric, respectively. In acetic add solution they are monomeric because of stronger solute-solvent interaction which accounts for all the H bonding. [Pg.1248]

The zinc enamine EtZn(Bu NHCH=CHNEtBu ), obtained from Et2Zn and Bu N=CHCH=NBu , forms dimeric zinc-aldolates on reaction with aldehydes. The dimeric zinc-aldolate fromp-HCOCsHtN forms a coordination polymer with Vi equivalent Et2Zn. The X-ray structure of the polymer, in which the pyridine nitrogens are coordinated to bridging Et2Zn units, shows the monomeric zinc-aldolate units to have a distorted boat conformation. The synthesis and characterisation of trimeric [1-EtZnNH-naphthalene.THF]3 (7) and [EtZnP(cyclohexyl)2]j.THF (8), have been described (7) contains 4-coordinate Zn and a cyclic Zn N3 core while in (8), which has a cyclic Zn3 3 ccrystal structure of (2-IZn-l,3-xylene)-1 S-crown-4 has also been reported. ... [Pg.17]


See other pages where Naphthalene trimers is mentioned: [Pg.31]    [Pg.444]    [Pg.356]    [Pg.138]    [Pg.56]    [Pg.234]    [Pg.193]    [Pg.194]    [Pg.172]    [Pg.403]    [Pg.148]    [Pg.54]    [Pg.308]    [Pg.444]    [Pg.392]    [Pg.49]    [Pg.248]    [Pg.139]    [Pg.172]    [Pg.18]    [Pg.266]    [Pg.49]    [Pg.276]    [Pg.280]    [Pg.200]    [Pg.200]    [Pg.268]    [Pg.101]    [Pg.7872]    [Pg.260]    [Pg.146]   


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