3- methylindene

G-9 Aromatic Petroleum Resins. Feedstocks typically used for aromatic petroleum resin synthesis boil in the approximate range of 100—300°C at atmospheric pressure, with most boiling in the 130—200°C range. The C-9 designation actually includes styrene (C-8) through C-10 hydrocarbons (eg, methylindene). Many of the polymerizable monomers identified in Table 1 for coumarone—indene type cmdes from coal tar are also present in aromatic fractions from cracked petroleum distillates. Therefore, the technology developed for the polymerization of coal-tar cmdes is also appHcable to petroleum-derived aromatic feedstocks. In addition to availabiHty, aromatic petroleum resins offer several advantages over coumarone—indene resins. These include improved color and odor, as weU as uv and thermal stabiHty (46). 

The main impurity in cmde 78°C coal-tar naphthalene is sulfur which is present in the form of thionaphthene (1—3%). Methyl- and dimethylnaphthalenes also are present (1—2%) with lesser amounts of indene, methylindenes, tar acids, and tar bases. 

According to the submitter, acidification of the combined sodium bicarbonate washings with 10% hydrochloric acid yields a colorless precipitate of 6,7-dimethoxy-3-methylindene-2-car-boxylic acid, which is collected by filtration, washed, and dried yield, 3.4-3.Q g. (14-16%) m.p. 216-218°. 

The 5-methyl analog 2 gives the 3/7-indazole 3 and 3-methylindene in this reaction.123... 

The lithium-(-)-sparteine complex, generated by deprotonation of 1-methylindene, does not lose its configuration in diethyl ether solution even at room temperature80 presumably, the observed major diastcreonier is the thermodynamically determined product. Substitution with carbonyl compounds leads to 1-substituted (fl)-l-methyl-l//-indenes with >95% ee in high yields81. 

Polyphosphoric acid in cyclization of ethyl a-acetyl-/3-(2,3-dimethoxy-phenyl)propionate to 6,7-dimeth-oxy-3-methylindene-2-carboxyl-ate, 40, 43... 

Matsson (1985) determined the secondary /3-deuterium KIE for the base-catalysed stereospecific 1,3-prototropic rearrangement (37) of 1-methylindene... 

Table 32 Primary and secondary j3-deuterium KIEs for the rearrangement of 1-methylindene to 3-methylindene using the rigid amines [8]—[11] as catalysts in toluene and DMSO at 20°C. ...

An alternative to evaluating the KIE and the rate constants from the above equations is to apply nonlinear least-squares fitting to the complete kinetic set of a and t values. This latter procedure has the advantage that errors in the reaction model, e.g. an incorrect mechanism, or extraneous data points are more easily discovered. This method was applied by Bergson et al. (1977) and Matsson (1985) in the determination of both the primary deuterium and secondary a-deuterium KIEs in the 1-methylindene rearrangement to 3-methylindene (reaction (67)). For example, a secondary /3-deuterium KIE of 1.103 0.001 was determined very accurately in toluene at 20°C using this method (Bergson et al., 1977). 

Methylindene undergoes rapid rearrangement to 3-methylindene [13] via the conjugate base, when treated with aqueous sodium hydroxide and benzyltriethyl-ammonium chloride under reaction conditions similar to those described in 9.4.1. 

MethyUndanes, 20 281 Methylindene, cyclization, 28 298 Methylnaphthalene, cyclization, 28 298, 299 Methyl-N-phenylcarbamate synthesis, 41 226-227... 

The keto radical is reduced and further protonated. The function of yohimbine-H+ is to catalyze the tautomerization and to enantioselectively protonate the final carbanion. It is also concluded that the hydrophobic yohimbine is enriched near the hydrophobic cathode surface. Quantum chemical calculations demonstrate that si protonation of the intermediate anion by yohimbine-H+ to give the (i )-dihydroproduct is energetically favored [389, 390]. Similarly, 3-methylinden-l-one in the presence of strychnine yields 71% 3-methylindan-1-one with 35% ee (S -enantiomer). 

Results of a theoretical study of 1,3-prototropic rearrangement of 1-methylindene, catalysed by ammonia and MesN in water and in cyclohexane, have confirmed earlier predictions that the proton moves freely over the indene ring once it has been abstracted by the base. The relative rates of deprotonation, ion-pair collapse and ion-pair rearrangement have been estimated and discussed in each case. 

Pyrolysis of bis(2-ethylhexyl) phthalate in the presence of polyvinyl chloride at 600 °C produced the following compounds methylindene, naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, biphenyl, dimethylnaphthalene, acenaphthene, fluorene, methylacenaphthene, methylfluorene, phenanthrene, anthracene, methylphenanthrene, methylanthracene, methylpyrene or fluoranthene, and 17 unidentified compounds (Bove and Dalven, 1984). 

Methyl-A-hydroxythioacetimidate, see Methomyl Methylindene, see Bis(2-ethylhexyl) phthalate, Di-n-butyl phthalate... 

Platinum, the most studied metal, catalyzes both C5 and C6 cyclizations in parallel reactions. n-Butylbenzene, for example, gives methylindan and methylindenes,... 

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