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Phenolates, supported

The Michael reaction involving addition to carbon-carbon double bonds containing an electron-withdrawing group is catalysed by base. A variety of heterogeneous bases which can be reused are known, including alumina, KF on alumina and phenolates supported on silica, the last having proved particularly effective for addition of /3-keto esters to enones (Scheme 1.7). [Pg.24]

Fig. 3 Bis(phenolate)-supported dimeric lithium and potassium L-lactide polymerization initiators [36-43]... Fig. 3 Bis(phenolate)-supported dimeric lithium and potassium L-lactide polymerization initiators [36-43]...
Fig. 27 Amino bis(phenolate)-supported zirconium and hafnium complexes and Al-fluorous complexes for isoselective lactide ROP... Fig. 27 Amino bis(phenolate)-supported zirconium and hafnium complexes and Al-fluorous complexes for isoselective lactide ROP...
In photodetachment studies we need not be concerned with the coulombic interaction that dominates the neutralization channel in MPI at times <10 ° s, but since the threshold for ionization of an anion is higher in the liquid than in the gas phase, we obtain once again information on the polarization energy of the ion in the liquid prior to photo-detachment. The laser photodetachment mechanism has been used with inorganic ions, such as Fe(CN)g or organic ions such as phenolate, supported in a wide range of aqueous or organic liquids. [Pg.542]

Cu(OAc)2 Solid-supported catalyst, good yields, good substrate scope, including orlho-substitution on phenol Supported Cu (1.5 equiv), ArB(OH)2 (3 equiv), EtjN (2.6equiv), 4A MS, CHjOj, rt, 24h 13]... [Pg.127]

Dihydropyrano[3,2-c]chromenes have recently attracted much attention as an important class of heterocycles having useful biological and pharmacological properties such pyran-annulated scaffolds are obtained from the reaction of 4-hydroxycoumarin (13) with aldehydes and C-H activated acids (e.g., malononitrile, ethyl 2-cyanoacetate, etc.). Recently, Khoobi et al. [95] developed an efficient protocol for the synthesis of dihydropyrano[3,2-c]chromenes 14 in aqueous medium in the presence of nanocatalyst, (2-aminomethyl)phenol, supported on HAp-encapsulated-Y-Fe203 ([Y-Fe203 Hap-Si(CH2)3-AMP]) under reflux condition (Scheme 7). "Qn-water" syntheses of such scaffolds were also reported earlier by Khurana et al. [81] and Shaabani et al. [86] (Scheme 7). [Pg.190]

The theory that the catalysed nitration proceeds through nitrosation was supported by the isolation of some />-nitrosophenol from the interrupted nitration of phenol, and from the observation that the ortho.-para ratio (9 91) of strongly catalysed nitration under aqueous conditions was very similar to the corresponding ratio of formation of nitrosophenols in the absence of nitric acid. ... [Pg.57]

Propylation of benzene with propylene, catalyzed by supported phosphoric acid (or related catalysts such as AlCl ), gives cumene [98-82-8] in another important industrial process. Cumene (qv), through the intermediacy of cumene hydroperoxide, is used in the manufacture of phenol (qv). Resorcinol similarly can be made from y -diisopropylbenzene (6). [Pg.551]

Starting from Benzene. In the direct oxidation of benzene [71-43-2] to phenol, formation of hydroquinone and catechol is observed (64). Ways to favor the formation of dihydroxybenzenes have been explored, hence CuCl in aqueous sulfuric acid medium catalyzes the hydroxylation of benzene to phenol (24%) and hydroquinone (8%) (65). The same effect can also be observed with Cu(II)—Cu(0) as a catalytic system (66). Efforts are now directed toward the use of Pd° on a support and Cu in aqueous acid and in the presence of a reducing agent such as CO, H2, or ethylene (67). Aromatic... [Pg.489]

Dehydrogenation. Before the large-scale availabiUty of acetone as a co-product of phenol (qv) in some processes, dehydrogenation of isopropyl alcohol to acetone (qv) was the most widely practiced production method. A wide variety of catalysts can be used in this endothermic (66.5 kj/mol (15.9 kcal/mol) at 327°C), vapor-phase process to achieve high (75—95 mol %) conversions. Operation at 300—500°C and moderate pressures (207 kPa (2.04 atm)) provides acetone in yields up to 90 mol %. The most useful catalysts contain Cu, Cr, Zn, and Ni, either alone, as oxides, or in combinations on inert supports (see Catalysts, supported) (13-16). [Pg.105]

AcOEt, AI2O3, 75-80°, 24 h, 45-69% yield. This method is selective for primary alcohols. Phenols do not react under these conditions. The use of Si02 NaHS04 as a solid support was also found to be effective. [Pg.89]

In lithium-ion battery applications, it is important to reduce the cost of electrode materials as much as possible. In this section, we will discuss hard carbons with high capacity for lithium, prepared from phenolic resins. It is also our goal, to collect further evidence supporting the model in Fig. 24. [Pg.375]

The mechanism of this reaction has been studied by several groups [133,174-177]. The consensus is that interaction of ester with the phenolic resole leads to a quinone methide at relatively low temperature. The quinone methide then reacts rapidly leading to cure. Scheme 11 shows the mechanism that we believe is operative. This mechanism is also supported by the work of Lemon, Murray, and Conner. It is challenged by Pizzi et al. Murray has made the most complete study available in the literature [133]. Ester accelerators include cyclic esters (such as y-butyrolactone and propylene carbonate), aliphatic esters (especially methyl formate and triacetin), aromatic esters (phthalates) and phenolic-resin esters [178]. Carbamates give analogous results but may raise toxicity concerns not usually seen with esters. [Pg.916]

The decrease in rate was proportional to the concentration of dioxane in the reaction mixture. An equivalent concentration of p-xylene (whose dielectric constant is similar to that of dioxane) produced a smaller decrease, consistent with simple dilution of the reactants. It was, therefore, hypothesized that dioxane forms an H-bonded molecular complex with phenol, the complexed form of the phenol being unreactive. The data could be accounted for with a 2 1 stoichiometry (phe-nokdioxane). This argument was supported by experiments with tetrahydrofuran, which also decreased the rate, but which required a 1 1 stoichiometry to describe the rate data. [Pg.404]

The allcylation of a number of aromatic compounds through the use of a chloroa-luminate(III) ionic liquid on a solid support has been investigated by Holderich and co-workers [87, 88]. Here the allcylation of aromatic compounds such as benzene, toluene, naphthalene, and phenol with dodecene was performed using the ionic liquid [BMIM]C1/A1C13 supported on silica, alumina, and zirconia. With benzene, monoalkylated dodecylbenzenes were obtained (Scheme 5.1-56). [Pg.201]

To support a polystyrene onto the upper rim of ca-lix[4]arene (phenolic-O- of calix[4]arene) and 25,26,27-tribenzoyloxy-28-hydroxy, calix[4]arene was treated with chloromethylated polystyrene in the presence of K2CO3 (Scheme 7). Polymeric calix[4]arene (3a) thus obtained was hydrolyzed in the benzoyl groups prior to use for the extraction process. [Pg.345]

There is a difference in the behavior of benzenediolatoborate and naphthalenedio-latoborate solutions on the one hand, and lithium bis[2,2 -biphenyldiolato(2-)-0,0 ] borate (point 5 in fig. 8) lithium bis[ sali-cylato (2-) Jborate (point 6) or benzene-diolatoborate/phenolate mixed solutions on the other (Fig.8). This can be tentatively explained by the assumption of different decomposition mechanisms due to different structures, which entail the formation of soluble colored quinones from benzenediolatoborate anions and lithium-ion conducting films from solutions of the latter compounds (points 5 and 6) [80], The assumption of a different mechanism and the formation of a lithium-ion conducting, electronically insulating film is supported by... [Pg.477]


See other pages where Phenolates, supported is mentioned: [Pg.457]    [Pg.393]    [Pg.330]    [Pg.191]    [Pg.197]    [Pg.457]    [Pg.393]    [Pg.330]    [Pg.191]    [Pg.197]    [Pg.671]    [Pg.679]    [Pg.64]    [Pg.41]    [Pg.290]    [Pg.291]    [Pg.404]    [Pg.405]    [Pg.54]    [Pg.208]    [Pg.151]    [Pg.228]    [Pg.330]    [Pg.40]    [Pg.174]    [Pg.28]    [Pg.898]    [Pg.900]    [Pg.903]    [Pg.917]    [Pg.930]    [Pg.197]    [Pg.226]    [Pg.19]    [Pg.339]    [Pg.515]   
See also in sourсe #XX -- [ Pg.92 ]




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