Pseudo cumene

Occasionally you might come across a compound called pseudo-cumene, which is a benzene ring connected to three methyl groups. This compound is an isomer of cumene known as 1,2,4-trimethyl benzene. Pseudo-cumene is a starting material for the manufacture of trimilletic anhydride, an important ingredient in alkyd resin paints and high temperature aerospace poiyimide resins. 

Composition of the volatile aromatic hydrocarbons obtained on HZSM5 shows the following changes with time on stream (Table 3). In the early product (38 minutes from start) m-xylene, p-xylene, pseudo-cumene and durene are the... 

Dimethylbenzylazide 1 -Azide-pseudo cumene or 1 -Azido-1,2,4-trimethyl benzene,... 

Difficulties met in separating chemical individuals from higher fractions of light oil and lower fractions of middle oil stimulated attempts at the direct nitration of solvent-naphtha, the name given to a mixture of isomers comprising xylenes, ethylbenzene, pseudo-cumene (1,2,4-trimethylbenzene), ethyltoluene and mesitylene. 

Pseudo-cumene, 1-2-4-Tri-methyl benzene, unsymmetrical. Hemelithene, 1-2-3-Tri-methyl benzene, vicinal. 

Pseudo-cumene, 1-2-4-Tri-methyl Benzene.—The second hydrocarbon, isomeric with mesitylene, and therefore tri-methyl benzene, is known as pseudo-cumene. It occurs also in coal tar, and resembles mesitylene in its properties. Its boiling point is 169°. Its structure is proven to be 1-2-4-tri-methyl benzene from the following reactions. 

Pseudo-cumene from Brom para-Xylene and Brom meta-Xylene. Bl om para-xylene, as will be recalled from the discussion of the constitution of para-xylene, exists only in one form as no isomeric compounds are possible. This substance, by means of Fittig s synthesis, yields pseudo-cumene, the constitution of which, therefore, can only be I-3-4-tri-methyl benzene. 

Dimethyibenzylazide 1 Azido-pseudo cumene or 1 Azido-l,2,4-trimethylbenzene,... 

There are several isomeres of this substance, among which are pseudo cumene, or trimethylrbenzme, CJH, (CH,) and metitylene, or methyl-ethyl-benzene, (OU,)(0,IU conet nding to a seriea of derivatives. 

In the di-substituted benzene series o- and m-xylene give the expected products. However, p-xylene undergoes isomerisation to furnish 2,4-dimethylbenzaldehyde. The tri-substituted benzene series i.e. mesitylene and pseudo-cumene yield normal formylation products. Tetralin and di-isopropyltetralin in the naphthalene series are reported to undergo Gattermann-Koch formylation whereas naphthalene itself is formylated in the modified reaction using HF and BF3 as catalyst. 

D. P. Roelofsen (Technological University, Delft, Netherlands) In your adsorption experiments, you tried to reach equilibrium by working at 100°C. In view of the earlier paper presented by Satterfield and Katzer which showed a very slow counterdiffusion of molecules such as 1-methyl-naphthalene and cumene, I would imagine that the counterdiffusion of your 2,6- and 2,7-DMN would be even slower. This could well mean that you reach a pseudo-equilibrium in which the ratio 2,6 2,7 isomer is kinetically determined. In L sieve, one then would expect that 2,6-DMN, which is the more linear of the two, would be preferred by the onedimensional channel system, in agreement with your data. With X and Y sieves, one can imagine that the nonlinear 2,7-DMN has just the right... 

SwnmaiT of the Cumene Decompo.sition 680 Reforming Catalysts 681 Rate Laws Derived from the Pseudo-Steady-State Hypothesis 684 Tempertnure Dependence of the Rate Law... 

The catalytic cracking of cumene to propylene and benzene was studied at 800°F using a fiuidized bed 3 inches in diameter [7]. The silica-alumina catalyst had 13% AI2O3 and a BET surface of 490 m /g. The 100-to 200-mesh fraction of the catalyst was used after fiuidizing for several hours to remove fines. The predicted equilibrium conversion was 0.77, and in many of the fixed bed tests this value was almost reached. With a porous-plate distributor and 8-inch initial bed height, the conversion was 62% at 0.1 ft/sec and 50% at 0.2 ft/sec. Treating the reaction as pseudo-first-order, Nf was estimated to be 8.4 for 0.1 ft/sec and 4.2 for 0.2 ft/sec. 

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