Abstract: The present invention relates to a method of working up an aluminum-containing reaction product from the production of isopulegol by cyclization of citronellal in the presence of complex compounds, comprising at least one ligand of the formula (I), where R1, R2, R3 are chosen from hydrogen, halogen, nitro, C1-C8-alkyl, C1-C8-alkoxy, di(C1-C4-alkyl)amino and aryl; R4, R5 are chosen from halogen, nitro, C1-C8-alkyl, C1-C8-alkoxy, di(C1-C4-alkyl)amino, aryl or heteroaryl; in which a) the reaction product is subjected to distillative separation to obtain an isopulegol-enriched top product and an isopulegol-depleted bottom product and b) the ligand of the formula (I) is separated off from the bottom product. Moreover, the invention relates to a method of producing isopulegol, and to a method of producing menthol.

Abstract: The present invention relates to a method of working up an aluminium-containing reaction product from the production of isopulegol by cyclization of citronellal in the presence of complex compounds, comprising at least one ligand of the formula (I), where Ar1, Ar2, Ar3, Ar4 are chosen from C6-C15-aryl or C2-C15-hetero; R1, R2, R3, R4 are chosen from H, C1-C6-alkyl, C1-C6-perfluoroalkyl, C1-C6-alkoxy, C7-C12-aralkyl, halogen, SiR5bR6bR7b, C6-C10-aryl, NR8bR9b, SR10b, NO2; and where R1 or R2 and/or R3 or R4, together with A, can form an aromatic or nonaromatic cycle; etc.; in which a) the aluminum-containing reaction product is subjected to distillative separation, b) the isopulegol-depleted bottom product is brought into close contact with an aqueous base and c) the ligand of the formula (I) is separated off from the organic phase, preferably by crystallization. Moreover, the invention relates to a method of producing isopulegol, and to a method of producing menthol.

Abstract: The present invention relates to diarylphenoxyaluminum compounds which are obtainable by reacting a bis(diarylphenol) ligand of the formula (I) with an alkylaluminum compound and/or a complex aluminum hydride. The invention moreover relates to the use of such diarylphenoxyaluminum compounds as catalysts. Moreover, the invention relates to a method of producing isopulegol by cyclization of citronellal in the presence of diarylphenoxyaluminum compounds as catalysts. The invention also relates to a method of producing menthol by cyclization of citronellal in the presence of diarylphenoxyaluminum compounds as catalysts and subsequent hydrogenation.

Abstract: The present invention relates to a process for the preparation of isopulegol of formula (I): comprising the cyclization of citronellal of formula (II): in the presence of a tris(aryloxy)aluminum catalyst, wherein the cyclization is carried out in the presence of I. at least one acid and/or II. at least one compound selected from the group comprising carboxylic anhydrides, aldehydes, ketones and vinyl ethers.

Abstract: The present invention relates to a process for preparing optically active aldehydes or ketones which have from 3 to 25 carbon atoms and at least one racemizable stereocenter by catalytic dehydrogenation of the corresponding optically active primary or secondary alcohols in the gas phase in the presence of a catalyst.

Abstract: The present invention relates to a process for preparing enriched isopulegol by crystallization from a melt comprising isopulegol. The invention relates specifically to a process for preparing enantiomerically enriched n-isopulegol proceeding from optically active isopulegol having a relatively low enantiomeric excess by crystallization from the melt. The invention further relates to a process for preparing menthol proceeding from enantiomerically and/or diastereomerically enriched n-isopulegol prepared by crystallization from the melt.

Abstract: The present invention relates to a process for the preparation of isopulegol of formula (I): comprising the cyclization of citronellal of formula (II): in the presence of a tris(aryloxy)aluminum catalyst, wherein the cyclization is carried out in the presence of I. at least one acid and/or II. at least one compound selected from the group comprising carboxylic anhydrides, aldehydes, ketones and vinyl ethers.

Abstract: The present invention relates to diarylphenoxyaluminum compounds which are obtainable by reacting a bis(diarylphenol) ligand of the formula (I) with an alkylaluminum compound and/or a complex aluminum hydride. The invention moreover relates to the use of such diarylphenoxyaluminum compounds as catalysts. Moreover, the invention relates to a method of producing isopulegol by cyclization of citronellal in the presence of diarylphenoxyaluminum compounds as catalysts. The invention also relates to a method of producing menthol by cyclization of citronellal in the presence of diarylphenoxyaluminum compounds as catalysts and subsequent hydrogenation.

Abstract: Processes comprising: (a) enantioselectively hydrogenating a starting material comprising a component selected from geraniol, nerol and mixtures thereof to form optically active citronellol; (b) converting the optically active citronellol to optically active citronellal; (c) cyclizing the optically active citronellal to form a mixture comprising optically active isopulegol; and (d) subjecting the mixture to further processing comprising: (i) separating the optically active isopulegol from the mixture and hydrogenating the separated optically active isopulegol to form optically active menthol; or (ii) hydrogenating the optically active isopulegol in the mixture to form optically active menthol and separating the optically active menthol from the mixture.

Abstract: An electrolyte solution proposed for double layer capacitors contains at least one conducting salt comprising a cation having a maximum diameter<9.20 ? which additionally comprises substituents on the central atom which are not all the same and further contains at least one solvent comprising a functional group selected from lactones and nitrites. Such electrolyte solutions are superior to conventional electrolyte solutions at low temperatures when acetonitrile is the solvent, so that double layer capacitors provided with electrolyte solutions according to the invention have improved electrical properties at low temperatures.

Abstract: The invention relates to a process for preparing cyclohexanedicarboxylic acids or derivatives thereof, such as esters and/or anhydrides, encompassing the reaction of diene/maleic acid anhydride mixtures, in particular of butadiene/maleic acid anhydride mixtures or of mixtures of maleic acid anhydrides and C5-dienes to give alkyl-substituted or unsubstituted cyclohexenedicarboxylic acid anhydrides in the condensed phase, ester formation, and then hydrogenation to give the corresponding cyclohexanedicarboxylic acid derivative, and also to the use of the cyclohexanedicarboxylic acids or derivatives thereof prepared according to the invention as plasticizers for plastics.

Abstract: The present invention relates to a process for preparing optically active aldehydes or ketones which have from 3 to 25 carbon atoms and at least one racemizable stereocenter by catalytic dehydrogenation of the corresponding optically active primary or secondary alcohols in the gas phase in the presence of a catalyst.

Abstract: The invention relates to a process for preparing 4-[aminoalkoxy]benzylamines of the general formula (I) by catalytically hydrogenating 4-[aminoalkoxy]benzonitriles of the general formula (II) where, in the compounds of the general formulae I and II, R1 is C1-C8-alkylene, R2 and R3 are each independently C1-C8-alkyl or are joined to give a ring which may additionally contain a heteroatom, which comprises carrying out the hydrogenation at elevated pressure and elevated temperatures. The invention further relates to a process for preparing the intermediate (II).

Abstract: The invention relates to a method for producing macrocyclic ketones of general formula (I) by direct cyclisation of compounds of general formula (II) in the gas phase on a heterogeneous catalyst. In general formula (I), X represents a monounsaturated or polyunsaturated or saturated C10–C17 alkyl radical which can be optionally substituted by a C1–C6 alkyl radical, and in general formula (II), R1, R2 can respectively be the same or different and represent hydrogen or C1–C6 alkyl, and has the above-mentioned designation.

Abstract: The invention relates to a method for the production of 1,7 octadiene by reacting metathesis of cyclohexene with ethylene. The invention also relates to the production of 1,10-decandiol by hydroformulating 1,7 octadiene produced according to said method. The invention further relates to a method for the production of muscone or olefinically unsaturated analogs thereof using 1,10 decandiol which is obtainable in said manner.

Abstract: A process for the preparation of imidazo[1,2-a]-5,6,7,8-tetra hydropyridin-8-ones by reaction of ?-butyrolactones with imidazols, novel imidazo[1,2-a]-5,6,7,8-tetrahydropyridin-8-ones, and their use for the preparation of imidazo[1,2-a]pyridines are described.

Abstract: The invention relates to a method for producing dialdehydes and/or ethylenically unsaturated monoaldehydes by reacting at least one compound with at least two ethylenically unsaturated double bonds with carbon monoxide and hydrogen in the presence of a hydroformylating catalyst with at least one complex of a metal of subgroup VIII. The subgroup comprises at least pnicogen chelate ligands.

Abstract: The present invention relates to a process for isomerizing reactant allyl alcohols of the formula (I) to product allyl alcohols of the general formula (II) where R1 to R5 are each hydrogen or a mono- or polyunsaturated or saturated C1–C12-alkyl radical, which can be substituted or unsubstituted, in both directions of the equilibrium, which comprises isomerizing in the presence of a dioxotungsten(VI) complex of the general formula (III), where L1, L2 are each independently a ligand selected from the group consisting of the aminoalcohols, the aminophenols and mixtures thereof, m, n are each 1 or 2, new dioxotungsten(VI) complexes, and also their use.

Abstract: The present invention relates to a process for isomerizing reactant allyl alcohols to product allyl alcohols in the presence of a catalyst, wherein the reactant allyl alcohol is rearranged to product allyl alcohol in semicontinuous or continuous mode in a catalyst-containing suitable reactor. In particular, the process according to the invention is used to prepare linalool from Geraniol and/or nerol.

Abstract: The present invention relates to a process for the preparation of iron-doped ruthenium catalysts supported on carbon, and their use for the selective liquid phase hydrogenation of carbonyl compounds to give the corresponding alcohols, in particular for the hydrogenation of citral to give geraniol or nerol or of citronellal to give citronellol.