Process for the production of 2-alkoxy-4-alkenyl phenols
AssigneeHaarmann & Reimer GmbH
InventorsKurt Bauer, Reiner Molleken, Fritz Exner
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Abstract
The invention concerns new 2-alkoxy-4-alkenyl phenols of the formula ##STR1## wherein R.sub.1 is methyl or ethyl and R.sub.2 and R.sub.3 are different from one another and mean hydrogen or methyl; A process for the preparation of said 2-alkoxy-4-alkenyl phenols comprising condensing 2-alkoxy phenols with butyraldehyde or isobutyraldehyde in the presence of an acid catalyst and thermal splitting the condensation product in the presence of a catalyst; and the use of the new 2-alkoxy-4-alkenyl phenols as odorants.
Claims11
A process for the production of 2-alkoxy-4-alkenyl phenols of the formula ##STR5## in which R.sub.1 is methyl or ethyl whilst
- R.sub.2 and R.sub.3 which are different from one another, are hydrogen or methyl
- comprising reacting in a first stage 2-alkoxy phenols of the formula ##STR6## in which R.sub.1 has the meaning given above with butyraldehyde or isobutyaraldehyde at a temperature from 0.degree. to 100.degree. C in the presence of an acid catalyst selected from the group consisting of sulphuric acid, hydrochloric acid, phosphoric acid, pyrophosphoric acid, sulphonic acid and acidic inorganic or organic ion exchangers and subsequently thermally splitting the condensation product obtained in a second stage by heating it at a temperature from 150.degree. to 300.degree. C in the presence of a basic catalyst selected from the group consisting of alkali or alkaline earth metals, aluminium, zinc, cadmium and lead and the oxides, hydroxides, alcoholates, phenolates, alkyl carboxylates, carbonates, amides or hydrides of the aforementioned metals.
Dependencies are inferred from the claim text.