Process for the production of trimethylhydroquinone diesters and of trimethylhydroquinone
AssigneeDegussa-Huls AG
InventorsSteffen Krill, Horst Weigel, Nongyuan Shi, Hans J. Hasselbach, Klaus Huthmacher, Frank Hubner
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Abstract
An improved process for the production of 2,3,5-trimethylhydroquinone by rearrangement of 4-oxoisophorone (ketoisophorone, 3,5,5-trimethyl-2-cyclohexen-1,4-dione) to yield a trimethylhydroquinone diester and the subsequent saponification thereof. Trimethylhydroquinone is in turn an important starting material for the production of vitamin E.
Claims12
A process for the production of trimethylhydroquinone diesters (2) ##STR2## in which R represents an optionally substituted aliphatic, alicyclic or aromatic hydrocarbon residue and 2,3,5-trimethylhydroquinone (3) ##STR3## by reaction of 4-oxoisophorone (1) ##STR4## with an acylating agent in the presence of catalytic quantities of a protonic acid and optionally subsequent saponification of the initially formed trimethylhydroquinone ester, comprising:
- using as the protonic acid an acid having a Hammett constant H.sub.o of <--11.9 (superacidic acids).
Dependencies are inferred from the claim text.