Conoco Inc.

Continental Oil Company

John R Dodd

Dean R Weimer

William R Buck

Daniel H Ralston

A titanium oxide/magnesium sulfate/magnesium oxide catalyst which is an ortho-selective methylation catalyst can be made to exhibit higher conversion and activity index for phenol methylation by the application of pressure. The pressure can be applied throughout the methylation period or can be applied for a short time at the beginning of the methylation period and then ceased, while higher activity continues. The pressure activation effects are assisted by the presence of phenol, methanol and/or water.

Pressure activation of magnesium oxide catalysts

A process for converting anisoles to ortho-methylated phenolic products in high selectivity is disclosed. The process comprises passing methoxybenzene, o-methylmethoxybenzene, 2,6-dimethylmethoxybenzene, or mixtures thereof, over gamma-alumina in the presence of an effective amount of water at a temperature in the range of about 225.degree. to about 295.degree. C.

Process for converting anisoles to ortho-methylated phenolic products

An improvement in the method of terminating the preparation of vinyl halide-containing polymers is disclosed. The improvement comprises injecting into the polymerization reactor at the desired level of conversion a free radical inhibitor obtained by the alkylation of p-methoxyphenol with nonene. The free radical inhibitor also functions as an antioxidant in the polymer product.

Termination of vinyl halide polymerization

A mixture of 2,4-/2,5-xylenol can be alkylated with a suitable alkylating agent over a strongly acidic divinylbenzene-styrene copolymer to afford a greater amount of 4-t-alkyl-2,5-xylenol than 6-t-alkyl-2,4-xylenol provided the alkylation is carried out at a suitably low temperature of 60.degree. C. or less.

Selective alkylation of 2,5-xylenol in the presence of 2,4-xylenol

A mixture of 2,4-/2,5-xylenol can be alkylated with a suitable alkylating agent over a strongly acidic divinylbenzene-styrene copolymer to afford a greater amount of 4-t-alkyl-2,5-xylenol than 6-t-alkyl-2,4-xylenol provided the alkylation is carried out at a suitably low temperature of up to 60.degree. C.

Separating 2,5-xylenol from a mixture of 2,5-xylenol and 2,4-xylenol

The relative amount of 2,5-xylenol in a 2,4-/2,5-xylenol mixture is significantly increased by passage of the xylenol mixture together with a suitable tertiary-alkylating agent through a reactor packed with a polymer-bound sulfonic acid catalyst at temperatures of 65.degree.-95.degree. C. and, preferably, 80.degree.-90.degree. C. The product stream from such a reactor under these conditions based on a 50:50 mixture of the two isomers contains a much greater amount of 6-t-alkyl-2,4-xylenol (t-alkylated 2,4-xylenol) than 4-t-alkyl-2,5-xylenol (t-alkylated 2,5-xylenol); consequently the resulting unalkylated 2,4-/2,5-xylenol mixture is greatly enriched in 2,5-xylenol. Recovery of the unalkylated mixture by fractionation thus affords a crude 2,5-xylenol which can be further purified to give pure 2,5-xylenol.

Process for obtaining 2,5-xylenol from a 2,4-/2,5-xylenol mixture

A process for preparing 5-t-butyl alkylphenols from alkylphenols in high selectivity is disclosed, wherein the starting alkylphenol is a 3-alkylphenol or a 2,3-dialkylphenol and the alkyl group is a C.sub.1 -C.sub.6 primary alkyl. The process comprises reacting a 3-alkylphenol or a 2,3-dialkylphenol, wherein the alkyl group is a C.sub.1 -C.sub.6 primary alkyl, with isobutylene in the presence of a catalyst, which is a sulfonated polystyrene crosslinked with divinylbenzene, at a temperature of at least 100.degree. C.

Preparation of 5-t-butyl alkyl-substituted phenols

A process for preparing 6-t-butyl alkylphenols from alkylphenols in high selectivity is disclosed, wherein the starting alkylphenol is a 3-alkylphenol or a 2,3-dialkylphenol and the alkyl group is a C.sub.1 -C.sub.6 primary alkyl. The process comprises reacting a 3-alkylphenol or a 2,3-dialkylphenol, wherein the alkyl group is a C.sub.1 -C.sub.6 primary alkyl, with isobutylene in the presence of a catalyst, which is a sulfonated polystyrene crosslinked with a divinylbenzene, at a temperature of 50.degree. to 90.degree.C.

Preparation of 6-t-butyl alkyl-substituted phenols

A method is described for the selective dealkylation of 4-tertiary-alkyl-2,5-xylenol while it is admixed with 6-tertiary-alkyl-2,4-xylenol by contacting the mixture of alkylated xylenols with a polymer-bound sulfonic acid catalyst at temperatures of 60.degree. C. or less and pressures of from about 0.5 to 5 atmospheres. The method is useful in separating 2,4-/2,5-xylenol mixtures.

Selective dealkylation of 4-tertiary-alkyl-2,5-xylenol

Broadly, the present invention is directed to a process for preparing 1-methylnaphthalene and 2-methylnaphthalene wherein the process comprises reacting naphthalene and methanol in the vapor phase at elevated temperatures and optionally under pressure in the presence of an effective amount of activated alumina catalyst. In a preferred embodiment the invention is directed to a process for preparing 2-methylnaphthalene in high selectivity by reacting naphthalene and methanol in the vapor phase at elevated temperatures in the range of about 500.degree. to about 650.degree. C. in the presence of an effective amount of activated alumina catalyst.

Process for methylating naphthalene

A method of preparing carbon-carbon coupled condensation products of alkylphenols is disclosed. Briefly, the method comprises oxidation of certain specific alkylphenols using palladium acetate as the catalyst in acetic acid or other suitable solvent.

Oxidative coupling of alkylphenols

Trimethylhydroquinone (TMHQ) which is discolored in organic solution because of air oxidation can be made nearly colorless by addition of small amounts of alkali metal borohydride to the discolored solution. Products remaining in the TMHQ solution after discoloration removal can be extracted by water wash. This technique represents a very simple and efficient method for removing discoloration which has proved troublesome in the prior art.

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Ponca City, OK, United States of America

John R Dodd