Abstract
By a unique method applying gas chromatography, the relative rate of sulfonation of linear dodecylbenzenes and n-hexylbenzene by 20% oleum has been determined at 18°C.
The relative rate of linear dodecylbenzenes decreases as the position of aromatic nucleus is located toward the center of the alkylchain. The rate of 6-phenyl isomer is about 40% smaller than that of 1-phenyl isomer. And, the rate of n-hexylbenzene, having the half-length alkyl chain, is about 60% greater than that of -dodecylbenzene. It was shown that, also in the sulfonation of higher mono-alkylbenzene, there is still a pronounced selectivity owing to the steric hindrance of the alkyl chain.
By digesting at 50°C, the above selective sulfonation was eliminated, and some new product with lower boiling point appeared.
