Indans, alkylated

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. 

Gumylphenol. -Cumylphenol (PGP) or 4-(1-methyl-l-phenylethyl)phenol is produced by the alkylation of phenol with a-methylstyrene under acid catalysis. a-Methylstyrene is a by-product from the production of phenol via the cumene oxidation process. The principal by-products from the production of 4-cumylphenol result from the dimerization and intramolecular alkylation of a-methylstyrene to yield substituted indanes. 4-Cumylphenol [599-64-4] is purified by either fractional distillation or crystallization from a suitable solvent. Purification by crystallization results in the easy separation of the substituted indanes from the product and yields a soHd material which is packaged in plastic or paper bags (20 kg net weight). Purification of 4-cumylphenol by fractional distillation yields a product which is almost totally free of any dicumylphenol. The molten product resulting from purification by distillation can be flaked to yield a soHd form however, the soHd form of 4-cumylphenol sinters severely over time. PGP is best stored and transported as a molten material. 

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. 

Fluonnation and skeletal transformation of fluorinated cycloalkanes occurs in the reaction with antimony pentafluoride at high temperature [777] In the case of perfluorinated benzocyclobutanes, an unexpected alicyclic ring cleavage has been observed Perfluorinated alkyl benzocyclobutanes, when treated with antimony pentafluoride, ean be converted to perfluorinated styrenes and then transformed to perfluorinated indans [77S, 779]... 

The acidity of benzylic protons of aromatics complexed to transition-metal groups was first disclosed by Trakanosky and Card with (indane)Cr(CO)3 [61]. Other cases are known with Cr(CO)3 [62], Mn(CO)3 [63], FeCp+ [64, 65], and Fe(arene)2+ [31, 66] but none reported the isolation of deprotonated methyl-substituted complexes. We found that deprotonation of the toluene complex gives an unstable red complex which could be characterized by 13C NMR ( Ch2 = 4.86 ppm vs TMS in CD5CD3) and alkylated by CH3I [58] Eq. (13) ... 

The catalytic system used in the Pacol process is either platinum or platinum/ rhenium-doped aluminum oxide which is partially poisoned with tin or sulfur and alkalinized with an alkali base. The latter modification of the catalyst system hinders the formation of large quantities of diolefins and aromatics. The activities of the UOP in the area of catalyst development led to the documentation of 29 patents between 1970 and 1987 (Table 6). Contact DeH-5, used between 1970 and 1982, already produced good results. The reaction product consisted of about 90% /z-monoolefins. On account of the not inconsiderable content of byproducts (4% diolefins and 3% aromatics) and the relatively short lifetime, the economics of the contact had to be improved. Each diolefin molecule binds in the alkylation two benzene molecules to form di-phenylalkanes or rearranges with the benzene to indane and tetralin derivatives the aromatics, formed during the dehydrogenation, also rearrange to form undesirable byproducts. 

After reaction, any solid residue was filtered off and the liquid product was separated by distillation into a bottoms product and a distillate that included unreacted Tetralin and low-boiling products from both the coal and the Tetralin. As tetralin breaks down under dissolution conditions to form mainly the tetralin isomer 1-methyl indan, naphthalene and alkyl benzenes (4) it was assumed that no compound with a higher boiling point than naphthalene was formed from the solvent, and the distillation to recover solvent was therefore continued until naphthalene stopped subliming. Some residual naphthalene remained in the bottoms product its mass, as determined from nmr and elemental analysis, was subtracted from the mass of bottoms product recovered and included in the amount of distillate recovered. It was assumed that all naphthalene present came from the Tetralin, not the coal. However, as the amount of tetralin reacted was 10 times the amount of coal this assumption appears reasonable. 

Tetralin has been shown to undergo thermal dehydrogenation to naphthalene and rearrangement to methyl indan in either the absence or presence of free radical acceptors [ 1, 2]. The presence of free radical acceptors usually accelerates the rearrangement reaction. Even with alkylated Tetralins>... 

Group 13/15 compounds have a long-standing history in inorganic chemistry and have been known for almost two centuries. First reports on such compounds go back to 1809, when Gay Lussac synthesized F3B4—NH3,1 the historical prototype of a Lewis acid-base adduct, by reaction of BF3 and NH3. Since this initial study, numerous Lewis acid-base adducts of boranes, alanes, gallanes and indanes MX3, MF13 and MR3 (M = B, Al, Ga, In X = F, Cl, Br, I R = alkyl, aryl) of the type R3M <- ER 3 (E = N, P, As) (Type A) have been synthesized and... 

However, one of the most common mechanisms is undoubtedly proton transfer but whereas in alkene polymerizations this reaction leaves a terminal double bond, in arylene polymerizations these are generally not found. Instead the terminal group is usually a substituted indane formed by an internal Friedel-Crafts alkylation [8, 21, 23], e.g., for a-methyl styrene ... 

Alkylation of the 2-(l,2-dihydropyrid-2-yl)indane-l,3-diones (3) (Scheme 5.18) by traditional methods, using sodium hydride in apolar or dipolar solvents, leads to a mixture of the C2- and A-alkylated derivatives in moderate to low yield (Scheme 5.18). In contrast, two-phase alkylation results in almost complete regioselective N-alkylation in high yield [64],... 

It has been shown that, in the presence of lithium diethylamide at —70 °C, bromoben-zoic acids form arynes which may react with arylacetonitriles to yield, predominantly, 2-cyanobenzoic acids. The reaction of alkyl and aryl isocyanides with benzyne may yield benzamide derivatives, showing their ability to act as charge-reversed equivalents to isocyanates. The generation and cyclization of a benzyne-tethered alkyllithium have been reported, and lead to a convenient synthetic route for 4-substituted indans. ... 

Aromatics react with olefins very readily when potassium is used as a catalyst. However, potassium is less selective in catalyzing alkylation than sodium because an additional reaction yields indans, as reported by Schaap and Pines 24). Therefore, the products consist of mixtures of arylalkanes and indans the relative amount of each depends largely on the aromatic used (as shown in Table II). The degree of alkyl substitution of the o -carbon... 

Indan formation [Reactions (13)-(15)] represents an intramolecular alkylation of the aromatic ring by a carbanion. 

Electrophilic nitrations of aliphatic nitriles, carboxylic acids,carboxylic esters, ° and /3-diketones have been reported. The nitration of 2-alkyl-substituted indane-l,3-diones with nitric acid, followed by alkaline hydrolysis, is a standard laboratory route to primary nitroalkanes. ... 

Phenylalkenes also undergo intramolecular alkylation under Friedel-Crafts conditions to yield five- or six-membered cyclic products (indan or tetralin derivatives, respectively). This cyclialkylation145,146,175 may actually also be considered as an isomerization reaction. 

When cycloalkanes (cyclopentane, cyclohexane) alkylate benzene, cycloalkylben-zenes, as well as bicyclic compounds (indan and tetralin derivatives) and products of destructive alkylation, are formed.191192 Cyclohexane reacts with the highest selectivity in the presence of HF—SbF5 to yield 79% cyclohexylbenzene and 20—21% isomeric methylcyclopentylbenzenes.191... 

Benzocyclobutenes form a special class of cyclobutenes because the double bond is part of an aromatic ring. Perfluoro(3-alkyl-l,2-benzocyclobutenes) rearrange in the presence of anti-mony(V) fluoride to indanes via styrene intermediates.27-31 Thus, perfluorobenzocyclobutenes 34 give perfluoroindanes 35 in moderate yields.27... 

SE-Substitution has been found when a-bromoallylsilane 7 is treated with tert-alkyl chloride in the presence of TiCLt at —78°C to give 9440. The reaction with a-bromoethylbenzene under the same conditions yields the corresponding indane 96. Apparently, the intermediate 95 may further undergo an intramolecular Friedel-Crafts reaction under these conditions (equation 74)... 

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