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Aromatization ionic

Halogenated derivatives of the same kind are much more radiation resistant for aromatic than for alicyclic compounds. The resulting order is aromatic > ionic > alicyclic. Even when the... [Pg.196]

Polyester polyols, 25 464 468 Polyester resin(s), 11 302 coating resins, 7 104-106 cyclopentadiene and dicyclopentadiene applications, 8 230 flammability of, 20 115-116 properties in powder coating, 7 43t standard test methods for, 20 11 It unreinforced, 10 187t weathering of, 20 116 Polyester resin-based powder coatings, organic titanium compounds in, 25 125 Polyester resin composites, 26 762-763 Polyester resin formulations ingredients of, 20 96t unsaturated, 15 511-512 Polyesters, 10 185-189, 497 12 655-656. See also Thermoplastic polyesters Unsaturated polyesters acid resistance of, 20 7-8 antioxidant applications, 3 121 aromatic ionic, 23 722 based on 1,4-cyclohexanedimethanol, 12 674-675... [Pg.729]

Composed of aromatic aminoacids Active dye ligands Aromatic ionic interactions... [Pg.575]

Shirota H, Fukazawa H, Fujisawa T, Wishart JF (2010) Heavy atom substitution effects in non-aromatic ionic hquids ultrafast dynamics and physical properties. J Phys Chem B 114(29) 9400-9412.doi 10.1021/jpl021104... [Pg.274]

Chem. Descrip. Proprietary aromatic Ionic Nature Nonionic Uses Carrier for polyester Features No-odor Properties Liq. 100% cone. [Pg.1572]

Shirota, H. Funston, A. M. Wishart, J. F. Castner, E. W., Jr., (2005). Ultrafast dynamics of pyrrolidinium cation ionic liquids. Journal of Chemical Physics, 122,184512/1-12 Shirota, H. Wishart, J. F. Castner, E. W., Jr. (2007). Intermolecular interactions and dynamics of room temperature ionic liquids that have silyl and siloxy-substituted imidazolium cations. Journal of Physical Chemistry B, 111, 4819-4829 Shirota, H. Nishikawa, K. Ishida, T. (2009). Atom substitution effects of [XFg]- in ionic liquids. 1. Experimental study. Journal of Physical Chemistry B, 113, 9831-9839 Shirota, H. Fujisawa, T. Fukazawa, H. Nishikawa, K. (2009). Ultrafast dynamics in aprotic molecular liquids a femtosecond Raman-induced Kerr effect spectroscopic study. Bulletin of the Chemical Society of Japan, 82,1347-1366 Shirota, H. Fukazawa, H. Fujisawa, T. Wishart, J. F. (2010). Heavy atom substitution effects in non-aromatic ionic liquids Ultrafast dynamics and physical properties. Journal of Physical Chemistry B, 114, 9400-9412... [Pg.222]

In the iavestigation of the decomposition reaction of aryldia2onium tetrafluoroborates ia nitroben2ene, it was found that ia addition to uoroben2ene, 3,3 -dinitrobiphenyl was formed (67). An ionic type of arylation reaction seems to take place. Decomposition of aryldia2onium tetrafluoro-, tetrachloro-, and tetrabromoborates ia aromatic solvents leads to electrophilic ring arylation (68). [Pg.556]

Aromatic and heterocycHc compounds are formylated by reaction with dialkyl- or alkylarylformamides in the presence of phosphoms oxychloride or phosgene (Vilsmeier aldehyde synthesis) (125). The Vilsmeier reaction is a Friedel-Crafts type formylation (126), since the intermediate cation formed by the interaction of phosphoms oxychloride with formamide is a typical electrophilic reagent. Ionic addition compounds of formamide with phosgene or phosphoms oxychloride are also known (127). [Pg.559]

Nitrations are highly exothermic, ie, ca 126 kj/mol (30 kcal/mol). However, the heat of reaction varies with the hydrocarbon that is nitrated. The mechanism of a nitration depends on the reactants and the operating conditions. The reactions usually are either ionic or free-radical. Ionic nitrations are commonly used for aromatics many heterocycHcs hydroxyl compounds, eg, simple alcohols, glycols, glycerol, and cellulose and amines. Nitration of paraffins, cycloparaffins, and olefins frequentiy involves a free-radical reaction. Aromatic compounds and other hydrocarbons sometimes can be nitrated by free-radical reactions, but generally such reactions are less successful. [Pg.32]

Most ionic nitrations are performed at 0—120°C. For nitrations of most aromatics, there are two Hquid phases an organic and an acid phase. Sufficient pressure, usually slightly above atmospheric, is provided to maintain the Hquid phases. A large interfacial area between the two phases is needed to expedite transfer of the reactants to the interface and of the products from the interface. The site of the main reactions is often at or close to the interface (2). To provide large interfacial areas, a mechanical agitator is frequently used. [Pg.32]

Ionic polymers are also formulated from TDI and MDI (43). Poly(urethane urea) and polyurea ionomers are obtained from divalent metal salts of /)-aminohen2oic acid, MPA, dialkylene glycol, and 2,4-TDI (44). In the case of polyureas, the glycol extender is omitted. If TDI is used in coatings apphcations, it is usually converted to a derivative to lower the vapor pressure. A typical TDI prepolymer is the adduct of TDI with trimethyl olpropane (Desmodur L). Carbodiimide-modified MDI offers advantages in polyester-based systems because of improved hydrolytic stabihty (45). Moisture cure systems based on aromatic isocyanates are also available. [Pg.350]

The interactions between solute and the pha.ses are exactly the same as those present in LC separations, namely, dispersive, polar and ionic interactions. At one extreme, the plate coating might be silica gel, which would offer predominately polar and induced polar interactions with the solute and, con.sequently, the separation order would follow that of the solute polarity. To confine the polar selectivity to the stationai y phase, the mobile phase might be -hexane which would offer only dispersive interactions to the solute. The separation of aromatic hydrocarbons by induced polar selectivity could be achieved, for example, with such a system. [Pg.443]

Studies of solvolysis of similar polyfluonnated polycyclic aromatic systems, such as 2,3-(tetrafluorobenzo)bicyclo[2 2 2]octadienes and related compounds, proved the ionic mechanism of this rearrangement [55, 36, 37] (equation 9) Possible nonclassical carbonium ion involvement has been discussed [5S, 39, 40, 41]... [Pg.915]

Trifluoromethanesulfonic (triflic) anhydride is commercially available or can be prepared easily by the reaction of triflic acid with phosphorus pentoxide [66] This moderately hygroscopic colorless liquid is a useful reagent for the preparation of various organic derivatives of triflic acid A large variety of organic ionic triflates can be prepared from triflic anhydride A recent example is the preparation of unusual oxo-bridged dicatiomc salts of different types [SS, 89, 90, 91, 92, 93] (equations 38-44) Stabilized dication ether salts of the Huckel aromatic system and some other systems (equations 38 and 39) can be prepared in one step by the... [Pg.956]

Silver(I) triflate is widely applied to the preparation of various derivatives of triflic acid, both covalent esters [66] and ionic salts For example, it can be used for the in situ generation of iodine([) triflate, a very effective lodinatmg reagent for aromatic and heteroaromatic compounds [130] (equations 65 and 66)... [Pg.965]

Cyclopentadienylsodium is ionic. Its anion is the aromatic cyclopentadienide ion, which contains six tt electrons. [Pg.609]

Many of the reactions of BF3 are of the Friedel-Crafts type though they are perhaps not strictly catalytic since BF3 is required in essentially equimolar quantities with the reactant. The mechanism is not always fully understood but it is generally agreed that in most cases ionic intermediates are produced by or promoted by the formation of a BX3 complex electrophilic attack of the substrate by the cation so produced completes the process. For example, in the Friedel-Crafts-type alkylation of aromatic hydrocarbons ... [Pg.199]


See other pages where Aromatization ionic is mentioned: [Pg.30]    [Pg.70]    [Pg.245]    [Pg.619]    [Pg.7989]    [Pg.2806]    [Pg.210]    [Pg.212]    [Pg.30]    [Pg.70]    [Pg.245]    [Pg.619]    [Pg.7989]    [Pg.2806]    [Pg.210]    [Pg.212]    [Pg.364]    [Pg.467]    [Pg.2593]    [Pg.146]    [Pg.1290]    [Pg.318]    [Pg.197]    [Pg.407]    [Pg.398]    [Pg.306]    [Pg.278]    [Pg.28]    [Pg.490]    [Pg.543]    [Pg.292]    [Pg.353]    [Pg.26]    [Pg.65]    [Pg.276]    [Pg.276]    [Pg.371]    [Pg.96]    [Pg.511]    [Pg.6]   
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