Alkylation Of P-cresol With Tert-butanol

2-tert-butyl p-cresol,as an important organic synthesis intermediate,has a good application prospect.The process of its synthesis has always been focus by researchers.In this paper,Some of the commercial zeolites such as HY,SSY,HPW-HMS,heteropolyacids,and heteropolyacid-supported zeolites were used as catalysts to investigate the catalytic activity of solid acids in the tert-butylation of p-cresol.Studies showed that the HY zeolite with a silica-alumina ratio of 5.4exhibits the highest catalytic activity in the reaction.The best synthetic parameters are:the reaction temperature is 140?,reaction time is 40 min,molar ratio of raw material is n_{?tert butyl alcohol?}:n_?p-cresol?=1.3.The conversion rate of cresol can reach72.9.1%with the yield of target product can reach 68.08%and selectivity was94.47%.according to the best synthesis process parameters.The main byproduct were p-toluene tert-butyl ether?TBPE?and 2,6-ditert-butyl-p-cresol?2,6-DTBC?.Compared with oil bath heating,the reaction time of microwave heating is only one eighth of that of oil bath heating,and the conversion of p-cresol is increased about three times.In this paper,[PY-BS]TsO,[PY-BS]HSO₄,[PY-BS]H₂PO₄,[PY-BS]Cl,[PY-BS]NO₃,[MIM-BS]TsO,[?CH₂?₄SO₃HTTsh]O,[?HSO₃-b?₂pi][HSO₄]acidic ionic liquids were synthesized from pyridine?PY?,N-methylimidazole?MIM?,thiazole,piperazine and 1,4-butane sulfolactone.The ionic liquids were characterized by TG-DTA,¹H NMR and FT-IR.The alkylation of p-cresol with tert-butanol catalyzed by various ionic liquids was investigated.Finally,[PY-BS]TsO was chosen as catalyst to investigate the effects of various reaction conditions on the reaction.The results shows that when the reaction temperature is 120?,the reaction time is8 h,n_{?tert-butanol?}:n_?p-cresol?=1.2,xylene is used as solvent,and the amount of ionic liquid is the same as that of p-cresol,the conversion of p-cresol can reach 77.94%,the yield of target product 2-TBC can reach 72.75%,and the selectivity is 93.34%.Whether HY zeolite or[PY-BS]TsO ionic liquids can be reused more than five times,and the catalytic activity has not been significantly reduced.