| abstract |
Ortho- and para-monoalkylated phenols and 2,4- and 2,6-dialkylphenols can be produced from phenolic compounds in good yields. The phenolic compound is reacted with an aldehyde having one to ten carbon atoms and a secondary aliphatic amine having a basic dissociation constant, pKb, of less than about 3.6 measured at 25 DEG C. The reaction is conducted in the liquid phase with at least a stoichiometric amount of the phenolic compound, the aldehyde and the secondary amine, or with an excess of the phenolic compound with the stoichiometric amounts of the aldehyde and the secondary amine. The reaction is conducted at a temperature in the range of around 0 DEG C. to about 25 DEG C., and the reaction produces an aminoalkylated phenol. The aminoalkylated phenol is contacted with hydrogen in the presence of a metal catalyst at a temperature of about 120 DEG C. to about 140 DEG C. at a hydrogen pressure not greater than 150 psi to produce a mixture of ortho-monoalkylphenol, para-monoalkylphenol and 2,4- and 2,6-alkylphenol. These compounds are separated to produce ortho-monoalkylphenol, para-monoalkylphenol, 2,4-dialkylphenol and 2,6-dialkylphenol. |