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Indenes 1-alkyl— from

Figure 2.7 contains plots of repetitive injection GC/MS chromatographic peak areas (integrated total ion current) as a function of sample temperature for benzene and styrene as well as selected products representing alkyl aromatics (ethyl benzene), indanes (methyl indane) and indenes (indene) evolved from PS-catalyst samples. The plots show that benzene is by far the most abundant volatile product. All of the PS-catalyst samples produce alkyl benzenes and indanes, however samples containing HZSM-5 catalyst generate significantly lower relative yields of these products. [Pg.54]

Takahashi T, Kuzuba Y, Kong E, Nakajima K, Xi Z (2005) Formation of indene derivatives from bis(cyclopentadienyl)titanacyclopentadienes with alkyl group migratitm via carhon-carbon bond cleavage. J Am Chem Soc 127 17188... [Pg.82]

Such copolymers of oxygen have been prepared from styrene, a-methylstyrene, indene, ketenes, butadiene, isoprene, l,l-diphen5iethylene, methyl methacrjiate, methyl acrylate, acrylonitrile, and vinyl chloride (44,66,109). 1,3-Dienes, such as butadiene, yield randomly distributed 1,2- and 1,4-copolymers. Oxygen pressure and olefin stmcture are important factors in these reactions for example, other products, eg, carbonyl compounds, epoxides, etc, can form at low oxygen pressures. Polymers possessing dialkyl peroxide moieties in the polymer backbone have also been prepared by base-catalyzed condensations of di(hydroxy-/ f2 -alkyl) peroxides with dibasic acid chlorides or bis(chloroformates) (110). [Pg.110]

AlClj Alkylation Process. The first step in the AIQ. process is the chlorination of / -paraffins to form primary monochloroparaffin. Then in the second step, the monochloroparaffin is alkylated with benzene in the presence of AIQ. catalyst (75,76). Considerable amounts of indane (2,3-dihydro-lH-indene [496-11-7]) and tetralin (1,2,3,4-tetrahydronaphthalene [119-64-2]) derivatives are formed as by-products because of the dichlorination of paraffins in the first step (77). Only a few industrial plants built during the early 1960s use this technology to produce LAB from linear paraffins. The C q—CC olefins also can be alkylated with benzene using this catalyst system. [Pg.51]

Ethyltoluene is manufactured by aluminum chloride-cataly2ed alkylation similar to that used for ethylbenzene production. All three isomers are formed. A typical analysis of the reactor effluent is shown in Table 9. After the unconverted toluene and light by-products are removed, the mixture of ethyltoluene isomers and polyethyltoluenes is fractionated to recover the meta and para isomers (bp 161.3 and 162.0°C, respectively) as the overhead product, which typically contains 0.2% or less ortho isomer (bp 165.1°C). This isomer separation is difficult but essential because (9-ethyltoluene undergoes ring closure to form indan and indene in the subsequent dehydrogenation process. These compounds are even more difficult to remove from vinyltoluene, and their presence in the monomer results in inferior polymers. The o-ethyltoluene and polyethyltoluenes are recovered and recycled to the reactor for isomerization and transalkylation to produce more ethyltoluenes. Fina uses a zeoHte-catalyzed vapor-phase alkylation process to produce ethyltoluenes. [Pg.489]

The highly aromatic resins are often used as coumarone/indene resin substitutes. A range of soft aromatic resins is available, produced from the alkylation of xylene and other aromatic hydrocarbons with dicyclopentadiene. These are excellent softeners for a wide range of rubbers. In common with other aromatic materials derived from petroleum sources, some of the resins used within the rubber industry are deemed to be carcinogenic. [Pg.160]

The intermediate vinylketene complexes can undergo several other types or reaction, depending primarily on the substitution pattern, the metal and the solvent used (Figure 2.27). More than 15 different types of product have been obtained from the reaction of aryl(alkoxy)carbene chromium complexes with alkynes [333,334]. In addition to the formation of indenes [337], some arylcarbene complexes yield cyclobutenones [338], lactones, or furans [91] (e.g. Entry 4, Table 2.19) upon reaction with alkynes. Cyclobutenones can also be obtained by reaction of alkoxy(alkyl)carbene complexes with alkynes [339]. [Pg.52]

Bromine-atom atomic resonance absorption spectrometry (ARAS) has been applied to measure the thermal decomposition rate constants of CF3Br in Kr over the temperature range 1222-1624 K. The results were found to be consistent with recently published theory. The formation of cyclopent[a]indene and acenaphthylene from alkyl esters of biphenyl-mono- and -di-carboxylic acids has been observed in flash vacuum pyrolyses at 1000-1100 °C. The kinetics and mechanisms of free-radical generation in the ternary system containing styrene epoxide, / -TsOH, and i-PrOH have been examined in both the presence and absence of O2. ... [Pg.130]

From a mechanistic point of view, it can be envisaged that this reaction proceeds via the desired benzylated pentanedione intermediate 14f. The subsequent intramolecular Friedel-Crafts alkylation of the electron-rich arene results in the quaternary benzyl alcohol II, which readily eliminates water to give the highly substituted indene 16 (Scheme 14). [Pg.125]

A bismuth-catalyzed alkylation of warfarins has not been described, although a bismuth-mediated synthesis of the coumarin core structure 21 starting from phenols 19 and ethyl acetoacetate 20 is known (Scheme 17) [51]. The synthesis of coumarins proceeds in the same way as the above-described indene synthesis. The initial reaction of phenol 19 and ethyl acetoacetate 20 leads to the ester. [Pg.126]

Consumption of the DSBPD results from further oxidation of the >NO radical (Reaction 12) but may also occur by hydrogen abstraction from the alkyl group leading to imine formation (5) or by disproportionation reactions yielding quinonoid structures (9). The existence of this reaction system may therefore be transitory. However, the main chain is long, and the effect of 7.5 X 10"3M DSBPD lasts almost throughout the oxidation of 0.15M indene-thiophenol (see Figure 3). [Pg.219]

About half of the 1-methylnaphthalene formed from n-pentylbenzene and 2-phenylpentane isomerizes to 2-methylnaphthalene over platinum on silica-alumina (while over platinum on silica less than 3% of the methylnaphthalene isomerizes to 2-methylnaphthalene). Alkylindan (and alkyl-indene) isomerization is also considerable over platinum on silica-alumina (13, 14). [Pg.307]

Titanium complexes derived from ethylene-bridged 2-indenyl ligands (Scheme 650) have been prepared by reductive dehydroxy coupling of 2-(hydroxymethyl)indenes with low-valent titanium compounds. Alkyl substitution of the indene ring at C(3) improves the regioselectivity of the reductive coupling.1671... [Pg.612]

Xanthenyliumsodium (from sodamide and xanthene) reacts with aziridines to give a mixture of 9-mono- (271) or 9,9-di-substituted xanthenes (272).Addition of perchloric acid to unsymmetric allenes such as the 9-xanthylidene derivative (273) (prepared by a new route from 9,9-dichloroxanthene and an alkene) gave a red xanthylium salt (274), which was converted into a colourless spiro-indene (275) on heating.Full details have now been published of the properties and of the reactions of 9-diazoxanthene (276) and 9-xanthylidene (278) with methyl acrylate, substituted styrenes, several ketones, and alkyl-benzenes. The kinetics of the reaction with styrenes were studied and the conversion of (276) into (278) was achieved by photolysis of the tosylhydrazone (277) at —25 °C. [Pg.316]

Free-radical Reactions.—number of further publications have appeared concerning the free-radical insertion of fluoro-olefins into C—H bonds (see Voi. 2, p. 122). Perokide-initiated reaction of toluene, and other alkyl benzenes having benzylic hydrogens, with hexafluoropropene yields mainly the adduct (89) and some of the indane (90) arising from cyclization of the initially formed radical, with subsequent dehydrogenation. The indane (90) yields the corresponding indene with ethanolic... [Pg.81]

Calix[n]arenes 1-3 were used as inverse PT catalysts in the alkylation of active methylene compounds with alkyl halides in aqueous NaOH solutions,and in aldol-type eondensation and Michael addition reactions. In the aikylation of phenylacetone with octyl bromide, the IPTC procedure enhanced the alkylation versus hydrolysis and C versus O alkylation selectivities with respect to those observed xmder classical PTC reactions in the presence of tetrabutylammonium bromide (TBAB) or hexadecyltributylammonium bromide (HTPB). Moreover, the aqueous catalyst solution was easily separated from the organic phase eontaining the products, and no organic solvent was required. In the case of the aldol-type condensation of benzaldehyde with indene or acetophenone in aqueous NaOH (Fig. 9), IPTC reaetions eatalyzed by I were compared with those conducted in aqueous micelles in the presence of cetyltrimethylammonium bromide (CTAB) as the sufactant. Although selectivities and yields were similar, the IPTC proeedure avoided the formation of emulsions, thus faciUtating product separation and catalyst recovery. In the light of the results obtained, water-soluble calix[ ]arenes 1-3 were proposed... [Pg.1046]


See other pages where Indenes 1-alkyl— from is mentioned: [Pg.627]    [Pg.64]    [Pg.132]    [Pg.93]    [Pg.184]    [Pg.260]    [Pg.260]    [Pg.427]    [Pg.421]    [Pg.492]    [Pg.4262]    [Pg.72]    [Pg.54]    [Pg.59]    [Pg.308]    [Pg.110]    [Pg.489]    [Pg.260]    [Pg.707]    [Pg.353]    [Pg.909]    [Pg.495]    [Pg.111]    [Pg.434]    [Pg.219]    [Pg.491]    [Pg.4261]    [Pg.308]    [Pg.19]    [Pg.265]    [Pg.934]    [Pg.1305]   


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Inden

Indene

Indenes 1- alkylation

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