Isobutylbenzene

PROPERTIES RESEARCH GRADE PURE GRADE TECHNICAL GRADE 

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Alternatively the alkylated aromatic products may rearrange. -Butylbenzene [104-57-8] is readily isomerized to isobutylbenzene [538-93-2] and j Abutyl-benzene [135-98-8] under the catalytic effect of Friedel-Crafts catalysts. The tendency toward rearrangement depends on the alkylatiag ageat and the reaction conditions (catalyst, solvent, temperature, etc). 

Isobutylbenzene is first acetylated to give isobutylacetophenone. 4-i-butylacetophenone (40 g), sulfur (11 g) and morpholine (30 ml) were refluxed for 16 hours, cooled, acetic acid (170 ml) and concentrated hydrochloric acid (280 ml) were added and the mixture was refluxed for a further 7 hours. The mixture was concentrated in vacuo to remove acetic acid and the concentrate was diluted with water. 

Show how ou might prepare the anti-inflammatory agent ibuprofen starting from isobutylbenzene. More than one step is needed. 

Isobutylbenzene Ibuprofen Pharma Nonsteroidal analgestic C (Homo Het) 1000 - 3000 STR... 

Of these, (S) is totally absent from the reaction products, while (T) is never more than a very minor product. On the other hand, (R) is produced in substantial amounts and one must conclude that opening in the fused C5 ring is strongly favored in a position adjacent to the benzene ring. Isobutylbenzene (U) is also produced in amounts somewhat in excess of sec-butylbenzene and this cannot be formed via a C5 carbocyclic route it is no doubt a product of a bond shift reaction... 

FIGURE 3.1.1.17.1 Logarithm of vapor pressure versus reciprocal temperature for isobutylbenzene. 

Ethylcyclop entanon e 3-Pentyl cyclopentanone 6-Methyl-3,5-heptadien-2-one 6-Methyl-2-cyclohexen-l-one 2,3-Dihydrocarvone Unidentified dimethylacetophenone 2-Butyrylfuran Dimethyl disulfide 2,6-Dimethylpyridine Isobutylbenzene Unidentified acetal (mol mass 154) Isobutyronitrile... 

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