Process for preparing hexamethyltetrahydronaphthalenes
AssigneeSumitomo Chemical Company, Limited
InventorsHiroshi Sato, Koiti Fujisawa, Hideto Tojima, Seimei Yasui
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Abstract
1,1,3,4,4,6-Hexamethyl-1,2,3,4-tetrahydronaphthalene (HMT), which is an intermediate for the production of acetyl HMT valuable in the art of perfumery because of its musk-like odor properties, is produced with industrial advantages by reacting p-cymene with 2,3-dimethylbutene using a catalytic amount of an anhydrous aluminum halide in the presence of at least one member selected from secondary alkyl halides, tertiary alkyl halides, propargyl halides and allyl halides; and 7-acetyl HMT is obtained by acetylation of the above-obtained HMT.
Claims18
A process for producing 1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene, which comprises reaction between p-cymene and a 2,3-dimethylbutene in an aliphatic hydrocarbon or cyclohexane solvent using a catalytic amount of anhydrous aluminum halide of the formula,
- AlX.sub.1 X.sub.2 X.sub.3
- wherein X.sub.1, X.sub.2 and X.sub.3 are the same or different, and are halogen atoms, provided that X.sub.1, X.sub.2 and X.sub.3 may not be all fluorine atoms, in the presence of secondary alkyl halides of formula (I), ##STR3## wherein R.sup.1 and R.sup.2 are each an alkyl group or may form a cyclic ring, and X is a halogen atom;
- tertiary alkyl halides of formula (II), ##STR4## wherein R.sup.1, R.sup.2 and R.sup.3 are each an alkyl group or two of them may form a cyclic ring, and X is a halogen atom;
- propargyl halides of formula (III),
- RC.tbd.C--CH.sub.2 --X (III)
- wherein R is a hydrogen atom or an alkyl group, and X is a halogen atom;
- or allyl halides of formula (IV),
- R--CH.dbd.CH--CH.sub.2 --X (IV)
- wherein R is a hydrogen atom or an alkyl group and X is a halogen atom.
Dependencies are inferred from the claim text.