ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Alkylation of phenol by triisobutylene

I. Hrabovecký, T. Fábry, and J. Paulen

Chemische Werke Georgi Dimitroff, Nationalunternehmen, Betriebsforschung, Bratislava

Abstract: The catalytic effect of 14 catalysts, some mixed with activated bentonite, was studied in the alkylation of phenol with triisobutylene for the prepn. of alkyl phenols with a longer branched side chain. The expts. were carried out at 80 to 130°, 3 mm. pressure, usually for 2 to 5 hrs., with some up to 20 hrs., in order to det. the effect of the catalyst on the yield and the compn. of the reaction products and the effect of the mol. ratio of the reaction components. At the alkylation with benzenesulfonic acid as a catalyst, the optimum parameters do not correspond to those of anhyd. AlCl₃ applied as a catalyst. The best results are obtained if the amt. of benzenesulfonic acid is 30-40% (on the wt. of phenol), if heated for 7 hrs. at 110-115°, and with the molar ratio 2:1. For AlCl₃, the amt. is 12.5-15% (on the wt. of phenol), 100-110° temp., heating time 8 hrs. and the molar ratio 2:1. For the identification of the alkyl phenols, chromatography on paper, in the system 30% dimethylformamide-n-heptane with a spray of FeCl₃ + K₃Fe(CN)₆ in the ratio 1:1 was applied. The product was sepd. into 4 fractions: (1) total, boiling above 60°, 3 mm.; (2) a lower boiling fraction at 60-130°, at 3 mm.; (3) higher boiling fraction above 130°, at 3 mm.; (4) the fraction boiling at 160-170°, 3 mm. It was detd. that all fractions including the one 160-170°, contain lower alkyl phenols, the tert-butylphenols and octylphenols. The exptl. work showed that it is possible to suppress the cleavage reactions and to select such reaction parameters so that the final product contains up to 85% octyl- and dodecylphenols, suitable as an additive to lubricants.

Full paper in Portable Document Format: 1910a755.pdf (in Slovak)

Chemical Papers 19 (10) 755–766 (1965)