Reference: Journal of Organic Chemistry. - 1951. - Vol. 16, No. 4 pp. 603 [doi: 10.1021/jo01144a011]
C6H5CH3 + (CH3)2C=CH2 → CH3C6H4C(CH3)3
Toluene (2 kg.) was chilled to -10° and 500 g. of 93% sulfuric acid was added, keeping the temperature below 0°; 350 liters of isobutene was passed in with vigorous agitation at a rate of 90 liters per hour, keeping the temperature between -5° and 0°. The toluene layer was washed to neutrality and distilled, yielding 1895 g. of p-tert-butyltoluene, b.p. 65–65°/10 mm. Oxidation with alkaline permanganate gave p-tert-butylbenzoic acid melting, alone or admixed with an authentic specimen, at 164°.
References:
CRC Handbook of Chemistry and Physics. - 95ed. - CRC Press, 2014. - pp. 3-86
Физико-химические свойства индивидуальных углеводородов. - М.: ГНТИНГТЛ, 1960. - pp. 36-37 [Russian]