Method for producing trimethylhydroquinone
AssigneeNippon Petrochemicals Company, Limited
InventorsKazuharu Suyama, Noboru Kiyota, Tomohiro Konishi, Yasuo Matsumura
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Abstract
An inexpensive method for producing trimethylhydroquinone free from the problem of the disposal of waste catalyst, which method comprises the steps of: (1) reacting isophorone in the presence of an acid catalyst and recovering β-isophorone by distillation, (2) oxidizing the β-isophorone in the presence of amorphous carbon and a base to obtain 4-oxoisophorone, (3) reacting the 4-oxoisophorone with an acid anhydride in a liquid phase or with a carboxylic acid in a vapor phase in the presence of a solid acid catalyst to obtain trimethylhydroquinones, and (4) hydrolyzing the trimethylhydroquinones to obtaining trimethylhydroquinone.
Claims13
A method for producing trimethylhydroquinone comprising:
- reacting isophorone in the presence of an acid catalyst and recovering β-isophorone by distillation;
- oxidizing said β-isophorone in the presence of amorphous carbon and a base to obtain 4-oxoisophorone;
- reacting said 4-isophorone in a vapor phase with a carboxylic acid in the presence of a solid acid catalyst to obtain at least one compound represented by the following formula:
- wherein R1 and R2 may be the same or different and are selected from hydrogen or an acyl group;
- and
- hydrolyzing compounds having at least one acyl group in the obtained reaction product represented by the formula, thereby obtaining trimethylhydroquinone,
- wherein said solid acid catalyst is a silica-alumina catalyst.
A method for producing trimethylhydroquinone comprising:
- reacting 4-isophorone in a vapor phase with a carboxylic acid in the presence of a solid acid catalyst to obtain at least one compound represented by the following formula:
- wherein R1 and R2 may be the same or different and are selected from hydrogen or an acyl group;
- and
- hydrolyzing compounds having at least one acyl group in the obtained reaction product represented by the formula, thereby obtaining trimethylhydroquinone,
- wherein said solid acid catalyst is a silica-alumina catalyst.
A method for producing trimethylhydroquinone comprising:
- reacting isophorone in the presence of an acid catalyst and recovering β-isophorone by distillation;
- oxidizing said β-isophorone in the presence of amorphous carbcon and an oxidation-resistant nitrogen-containing heterocyclic base to obtain 4-oxoisophorone;
- reacting said 4-isophorone in a vapor phase with a carboxylic acid or in the liquid phase with a carboxylic acid anhydride, the reacting being in the presence of a solid acid catalyst to obtain at least one compound represented by the following formula:
- wherein R1 and R2 may be the same or different and are selected from hydrogen or an acyl group;
- and
- hydrolyzing compounds having at least one acyl group in the obtained reaction product represented by the formula, thereby obtaining trimethylhydroquinone, wherein said acid catalyst is a silica-aluminum catalyst.
A method for producing trimethylhydroquinone comprising:
- reacting isophorone in the presence of an acid catalyst and recovering β-isophorone by distillation;
- oxidizing said β-isophorone in the presence of amorphous carbon and an oxidation-resistant nitrogen-containing heterocyclic base to obtain 4-oxoisophorone and to separate it by distillation to obtain refined 4-oxoisophorone;
- reacting said refined 4-oxoisophorone in a liquid phase with an excess of an acid anhydride in the presence of a solid acid catalyst to obtain at least one compound represented by the following formula:
- wherein R1 and R2 may be the same or different and are selected from hydrogen or an acyl group;
- recovering at least part of unreacted acid anhydride;
- and
- hydrolyzing compounds having at least one acyl group in the obtained reaction product represented by the formula, thereby obtaining trimethylhydroquinone, wherein said catalyst is a silica-aluminum catalyst.
A method for producing trimethylhydroquinone comprising:
- reacting isophorone in the presence of an acid catalyst and recovering β-isophorone by distillation;
- oxidizing said β-isophorone in the presence of amorphous carbon and an oxidation-resistant nitrogen-containing heterocyclic base to obtain 4-oxoisophorone and to separate it by distillation to obtain refined 4-isophorone;
- reacting 4-isophorone with at least one member selected from acid anhydrides or carboxylic acids in the presence of a solid acid catalyst to obtain at least one compound represented by the following formula:
- wherein R1 and R2 may be the same or different and are selected from hydrogen or an acyl group;
- and
- hydrolyzing the compound having at least one acyl group in the obtained reaction product represented by formula, thereby obtaining trimethylhydroquinone, wherein said catalyst is a silica-aluminum catalyst.
Dependencies are inferred from the claim text.