Abstract: Alcohols are prepared by electrochemical reductive coupling of an aromatic vinyl compound and a carbonyl compound in a process which comprises electrolyzing an electrolyte solution in an electrochemical cell, the electrolyte solution comprising the aromatic vinyl compound, the carbonyl compound and a non-aqueous protic solvent, such as methanol, wherein the electrolyte solution is in contact with a carbon-based cathode. Styrene is reacted with acetone to prepare 2-methyl-4-phenyl-2-butanol.

Abstract: Alcohols are prepared by electrochemical reductive coupling of an aromatic vinyl compound and a carbonyl compound in a process which comprises electrolyzing an electrolyte solution in an electrochemical cell, the electrolyte solution comprising the aromatic vinyl compound, the carbonyl compound and a non-aqueous protic solvent, such as methanol, wherein the electrolyte solution is in contact with a carbon-based cathode Styrene is reacted with acetone to prepare 2-methyl-4-phenyl-2-butanol.

Abstract: The invention relates to a process for the preparation of m- or p-substituted phenylalkanols of the formula (I) in which R1 is bonded to the phenyl ring in the m- or p-position and is C1-C5-alkyl, and R2, R3, R4 and R5, independently of one another, are hydrogen or methyl, wherein an unsubstituted phenylalkanol of the formula (II) in which R2, R3, R4 and R5 have the meanings given under formula (I) is alkylated together with a C1-C5-alkyl halide of the formula (III) R1-Hal??(III), in which R1 has the meaning given under formula (I) and Hal is halogen, in the presence of a Friedel-Crafts catalyst to give an m- or p-alkyl-substituted phenylalkanol of the formula (I), then the reaction mixture is worked-up and the desired m- or p-alkyl-substituted phenylalkanol of the formula (I) is separated off, the other formed by-products are returned to the reaction mixture and these are isomerized in the presence of a Friedel-Crafts catalyst to give the desired m- or p-alkyl-substituted phenylalkanol.

Abstract: The invention relates to a process for the preparation of m-substituted phenylalkanols of the formula (I) in which R1 is C1-C5-alkyl and R2, R3, R4 and R5, independently of one another, are hydrogen or methyl, wherein a p-substituted phenylalkanol of the formula (II) in which R1, R2, R3, R4 and R5 having the meanings given under formula (I), is isomerized in the presence of a Friedel-Crafts catalyst to give an m-substituted phenylalkanol of the formula (I). From the m-substituted phenylalkanols of the formula (I) it is possible to form, by oxidation or dehydrogenation, as products of value, the corresponding aldehydes, which are known as fragrances and aroma chemicals.

Abstract: The present invention relates to 3-tert-butylbenzaldehyde dimethyl acetal and to 3-tert-butylbenzyl methyl ether and to an electrochemical method for producing 3-tert-butyl-benzaldehyde dimethyl acetal and intermediates passed through in said method.

Abstract: The present invention relates to a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyranols by reacting 3-methylbut-3-en-1-ol (isoprenol) with the corresponding aldehydes in the presence of a strongly acidic cation exchanger. Specifically, the present invention relates to a corresponding process for the preparation of 2-isobutyl-4-hydroxy-4-methyltetrahydropyran by reacting isoprenol with isovaleraldehyde.

Abstract: The present invention relates to a process for preparing 2-methyl-3-(4-tert-butyl-phenyl)propanal with high para-isomer purity, and also to a process for preparing 4-tert-butylbenzaldehyde with high para-isomer purity.

Abstract: The invention relates to a process for the preparation of m-substituted alkyltoluenes of the formula (I) in which R1 is C1-C5-alkyl, wherein a p-substituted alkyltoluene of the formula (II) in which R1 has the meaning given under formula (I), is isomerized in the presence of ionic liquids to give an m-substituted alkyltoluene of the formula (I). The m-substituted alkyltoluenes obtainable according to the invention are starting compounds for the preparation of fragrances and aroma substances.

Abstract: The invention relates to a process for the preparation of m- or p-substituted phenylalkanols of the formula (I) in which R1 is bonded to the phenyl ring in the m- or p-position and is C1-C5-alkyl, and R2, R3, R4 and R5, independently of one another, are hydrogen or methyl, wherein an unsubstituted phenylalkanol of the formula (II) in which R2, R3, R4 and R5 have the meanings given under formula (I) is alkylated together with a C1-C5-alkyl halide of the formula (III) R1-Hal??(III), in which R1 has the meaning given under formula (I) and Hal is halogen, in the presence of a Friedel-Crafts catalyst to give an m- or p-alkyl-substituted phenylalkanol of the formula (I), then the reaction mixture is worked-up and the desired m- or p-alkyl-substituted phenylalkanol of the formula (I) is separated off, the other formed by-products are returned to the reaction mixture and these are isomerized in the presence of a Friedel-Crafts catalyst to give the desired m- or p-alkyl-substituted phenylalkanol.

Abstract: The invention relates to a process for the preparation of m-substituted phenylalkanols of the formula (I) in which R1 is C1-C5-alkyl and R2, R3, R4 and R5, independently of one another, are hydrogen or methyl, wherein a p-substituted phenylalkanol of the formula (II) in which R1, R2, R3, R4 and R5 having the meanings given under formula (I), is isomerized in the presence of a Friedel-Crafts catalyst to give an m-substituted phenylalkanol of the formula (I). From the m-substituted phenylalkanols of the formula (I) it is possible to form, by oxidation or dehydrogenation, as products of value, the corresponding aldehydes, which are known as fragrances and aroma chemicals.

Abstract: The present invention relates to a process for preparing 2-methyl-3-(4-tert-butyl-phenyl)propanal with high para-isomer purity, and also to a process for preparing 4-tert-butylbenzaldehyde with high para-isomer purity.

Abstract: The present invention relates to a process for the preparation of 2-substituted 4-hydroxy-4-methyltetrahydropyranols by reacting 3-methylbut-3-en-1-ol (isoprenol) with the corresponding aldehydes in the presence of a strongly acidic cation exchanger. Specifically, the present invention relates to a corresponding process for the preparation of 2-isobutyl-4-hydroxy-4-methyltetrahydropyran by reacting isoprenol with isovaleraldehyde.

Abstract: The present invention relates to 3-tert-butylbenzaldehyde dimethyl acetal and to 3-tert-butylbenzyl methyl ether and to an electrochemical method for producing 3-tert-butyl-benzaldehyde dimethyl acetal and intermediates passed through in said method.

Abstract: The invention relates to a process for the preparation of m-substituted alkyltoluenes of the formula (I) in which R1 is C1-C5-alkyl, wherein a p-substituted alkyltoluene of the formula (II) in which R1 has the meaning given under formula (I), is isomerized in the presence of ionic liquids to give an m-substituted alkyltoluene of the formula (I). The m-substituted alkyltoluenes obtainable according to the invention are starting compounds for the preparation of fragrances and aroma substances.

Abstract: The invention relates to a method for producing compounds of general formula (I), wherein Rt represents an oxocyclohexyl radical which is optionally substituted by a hydroxyl radical, an alkoxy radical, and/or alkyl radicals, or an oxocyclohexenyl radical which is optionally substituted by a hydroxyl radical, an alkoxy radical, and/or alkyl radicals, the oxo groups being in the form of an acetal, a ketone, or an enol ether, and R2 represents a hydroxy group or a protective group which can be transformed into a hydroxy group by means of hydrolysis. A compound of general formula (II) is cathodically reduced in a divided or partially divided electrolysis cell at a pH value of between 2 and 9.

Abstract: A method for producing compounds which are oxidized in an alpha position by electrochemical reaction with alcohol in the presence of an auxiliary electrolyte and catalytic amounts of a metal salt.

Abstract: A process for an electrochemical reduction of a reducible dye by contacting said reducible dye with a cathode comprising a support of an electrically conductive material and an electrically conductive, cathodically polarized layer formed thereon in situ by alluviation comprises conducting said electrochemical reduction in the presence of a base.

Abstract: A process is described for preparing diacetals of glyoxal by reacting from 40 to 75% by weight aqueous glyoxal with monohydric alcohols in the presence of an acid catalyst, which comprises leaving a liquid mixture which, at the beginning of the reaction, comprises alcohol and glyoxal in a molar ratio of at least 15:1 and also water in a concentration of not more than 8% by weight in contact with the acid catalyst until concentration in the reaction mixture of the diacetal formed reaches at least 70% of the equilibrium concentration without more than 5% by weight of the alcohol used having already been distilled off.

Abstract: A process for an electrochemical reduction of a reducible dye by contacting said reducible dye with a cathode comprising a support of an electrically conductive material and an electrically conductive, cathodically polarized layer formed thereon in situ by alluviation comprises conducting said electrochemical reduction in the presence of a base.

Abstract: A process is described for preparing diacetals of glyoxal by reacting from 40 to 75% by weight aqueous glyoxal with monohydric alcohols in the presence of an acid catalyst, which comprises leaving a liquid mixture which, at the beginning of the reaction, comprises alcohol and glyoxal in a molar ratio of at least 15:1 and also water in a concentration of not more than 8% by weight in contact with the acid catalyst until concentration in the reaction mixture of the diacetal formed reaches at least 70% of the equilibrium concentration without more than 5% by weight of the alcohol used having already been distilled off.