Abstract: The present invention relates to a process for preparing 3-methyl-2-butenol (prenol) and 3-methyl-2-butenal (prenal) from 3-methyl-3-butenol (isoprenol), in which 3-methyl-3-butenol is subjected to a catalytic isomerization over a carbon-supported Pd catalyst in the presence of a gas mixture comprising 1% to 15% by volume of oxygen to obtain a first product mixture, and the first product mixture is subjected to an oxidative dehydrogenation over a Pd catalyst comprising SiO2 and/or Al2O3 as support material, or over a carbon-supported Pd/Au catalyst in the presence of a gas mixture comprising 5% to 25% by volume of oxygen.

Abstract: A process for preparing an arylpropene from a diarylpropane by gas phase thermolysis in the presence of solid porous catalyst comprising silica having large pore volume and low acidity.

Abstract: The present invention relates to a process for preparing 3-methyl-2-butenol (prenol) and 3-methyl-2-butenal (prenal) from 3-methyl-3-butenol (isoprenol), in which 3-methyl-3-butenol is subjected to a catalytic isomerization over a carbon-supported Pd catalyst in the presence of a gas mixture comprising 1% to 15% by volume of oxygen to obtain a first product mixture, and the first product mixture is subjected to an oxidative dehydrogenation over a Pd catalyst comprising SiO2 and/or Al2O3 as support material, or over a carbon-supported Pd/Au catalyst in the presence of a gas mixture comprising 5% to 25% by volume of oxygen.

Abstract: A process for preparing an arylpropene from a diarylpropane by gas phase thermolysis in the presence of boron containing zeolitic material comprising a membered ring (MR) pore system greater than 10 MR.

Abstract: A process for preparing an arylpropene from a diarylpropane by gas phase thermolysis in the presence of solid porous catalyst comprising silica having large pore volume and low acidity.

Abstract: A process for preparing an arylpropene from a diarylpropane by gas phase thermolysis in the presence of boron containing zeolitic material comprising a membered ring (MR) pore system greater than 10 MR.

Abstract: The present invention relates to a method for the production of 2-substituted 4-hydroxy-4-methyltetrahydropyrans from the acid-catalyzed reaction of 3-methylbut-3-ene-1-ol with an aldehyde, a stable odoriferous quality being achieved and avoiding off-odors that interfere with the odor sensation.

Abstract: The present invention relates to a particularly economic overall method for producing menthol, specifically for producing optically active, essentially enantiomerically and diastereomerically pure L-menthol and racemic menthol, starting from the starting material citral which is available inexpensively on an industrial scale. The method has the following steps a.1) catalytic hydrogenation of neral and/or geranial to give citronellal, b.1) cyclization of citronellal to isopulegol in the presence of an acidic catalyst, c.1) purification of isopulegol by crystallization and d.1) catalytic hydrogenation of isopulegol to give menthol.

Abstract: The present invention relates to a process for preparing arylpropenes, especially 1-methoxy-4-(1-propenyl)benzene (anethole), by means of thermolysis of the corresponding 1,1-diarylpropanes.

Abstract: The present invention relates to processes for the preparation of compounds of the formula (Ia) by reacting styrene with a secondary alkanol and the hydrogenation of the resulting phenyl-substituted tertiary alkanol. In addition, the invention relates to compounds of the formula (Ia) and to the use of such compounds as fragrances, and also to compositions which comprise compounds of the formulae (Ia) and (Ib).

Abstract: The present invention relates to a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyrans.

Abstract: The invention relates to a method for producing 2-substituted 4-hydroxy-4-methyltetrahydropyrans.

Abstract: The present invention relates to a method for the production of 2-substituted 4-hydroxy-4-methyltetrahydropyrans from the acid-catalyzed reaction of 3-methylbut-3-ene-1-ol with an aldehyde, a stable odoriferous quality being achieved and avoiding off-odors that interfere with the odor sensation.

Abstract: The present invention relates to a process for preparing arylpropenes, especially 1-methoxy-4-(1-propenyl)benzene (anethole), by means of thermolysis of the corresponding 1,1-diarylpropanes.

Abstract: A process for preparing 4-cyclohexyl-2-methyl-2-butanol, comprising: a) reaction of styrene with isopropanol at elevated temperature to obtain 2-methyl-4-phenyl-2-butanol, and b) heterogeneously catalyzed hydrogenation of 2-methyl-4-phenyl-2-butanol over a catalyst suitable for ring hydrogenation of aromatics, where the molar ratio of the styrene used in step a) to the isopropanol used in step a) is in the range from 1:below 5 to 1:0.5.

Abstract: A process for preparing 4-cyclohexyl-2-methyl-2-butanol, comprising: a) reaction of styrene with isopropanol at elevated temperature to obtain 2-methyl-4-phenyl-2-butanol, and b) heterogeneously catalyzed hydrogenation of 2-methyl-4-phenyl-2-butanol over a catalyst suitable for ring hydrogenation of aromatics, where the molar ratio of the styrene used in step a) to the isopropanol used in step a) is in the range from 1:below 5 to 1:0.5.

Abstract: The present invention relates to processes for the preparation of compounds of the formula (Ia) by reacting styrene with a secondary alkanol and the hydrogenation of the resulting phenyl-substituted tertiary alkanol. In addition, the invention relates to compounds of the formula (Ia) and to the use of such compounds as fragrances, and also to compositions which comprise compounds of the formulae (Ia) and (Ib).

Abstract: The present invention relates to processes for the preparation of compounds of the formula (Ia) by reacting styrene with a secondary alkanol and the hydrogenation of the resulting phenyl-substituted tertiary alkanol. In addition, the invention relates to compounds of the formula (Ia) and to the use of such compounds as fragrances, and also to compositions which comprise compounds of the formulae (Ia) and (Ib).

Abstract: The invention relates to a method for producing 2-substituted 4-hydroxy-4-methyltetrahydropyrans.

Abstract: The present invention relates to a process for preparing 4,4?-[1-(trifluoromethyl)alkylidene]bis(2,6-diphenylphenols), in particular for preparing 4,4?-[1-(trifluoromethyl)ethylidene]bis(2,6-diphenylphenol), which comprises the self-condensation of cyclohexanone in the presence of a basic catalyst to form tricyclic condensation products, dehydrogenation of the resulting tricyclic condensation products in the presence of a supported transition metal catalyst in the condensed phase to form 2,6-diphenylphenol and reaction of the 2,6-diphenylphenol with a trifluoromethyl ketone. The invention further provides an improved process for preparing 2,6-diphenylphenol by aldol self-condensation of cyclohexanone.