Abstract: The present invention relates to the use of a compound of the general formula (I) wherein R1 is C1-C4-alkyl or —(C=0)—R3, R2 is hydrogen, C1-C4-alkyl or —(C=0)—R4, and R3 and R4, independently of one another, are selected from the group consisting of hydrogen and C1-C4-alkyl, a stereoisomer thereof or a mixture of stereoisomers thereof, as an aroma chemical, to aroma chemical compositions comprising at least one compound of the general formula (I), a stereoisomer thereof or a mixture of stereoisomers thereof, and to a method for preparing a fragranced ready-to-use composition, which comprises incorporating at least one compound of the general formula (I), a stereoisomer thereof or a mixture of stereoisomers thereof, into a ready-to-use composition. The present invention further relates to specific ethers and specific esters of the compounds of the general formula (I) and a method for their preparation.

Abstract: The present invention relates to a process for hydrogenating a mixture (G1) in the presence of a catalyst, where the mixture (G1) comprises at least one colorless amine and at least one color-imparting component. As a result of the hydrogenation step, the at least one color-imparting component is firstly partially, preferably fully, hydrogenated, while the colorless amine, in particular aniline, is not hydrogenated or hydrogenated to only a very small extent. The color-imparting components which cause the discoloration of the amine which is itself in principle colorless are thus removed by hydrogenation, as a result of which purification of the colorless amine or the mixture (G1) is achieved.

Abstract: The present invention relates to a process for hydrogenating a mixture (G1) in the presence of a catalyst, where the mixture (G1) comprises at least one colorless amine and at least one color-imparting component. As a result of the hydrogenation step, the at least one color-imparting component is firstly partially, preferably fully, hydrogenated, while the colorless amine, in particular aniline, is not hydrogenated or hydrogenated to only a very small extent. The color-imparting components which cause the discoloration of the amine which is itself in principle colorless are thus removed by hydrogenation, as a result of which purification of the colorless amine or the mixture (G1) is achieved.

Abstract: Processes for preparing tetrahydrofuran and/or butane-1,4-diol and/or gamma-butyrolactone are provided, including a process for preparing tetrahydrofuran (THF) from succinic acid that has been obtained by conversion of biomass, by conversion of the succinic acid to succinic anhydride, and hydrogenation of the succinic anhydride, with removal of certain secondary components.

Abstract: Process for preparing monoethylene glycol (MEG) by metal-catalyzed reaction of a dialkyl oxalate of the formula I where R1 and R2 are each, independently of one another, methyl, ethyl, n-propyl or isopropyl, with hydrogen (H2), wherein the dialkyl oxalate (I) is used as melt or as a solution in a solvent, dialkyl oxalate (I) and H2 are used in a molar ratio of H2:dialkyl oxalate (I) in the range from 4.0 to 30 and the reaction is carried out continuously in a reactor at a cross-sectional loading of ?10 m/s, a temperature in the range from 150 to 270° C., a pressure in the range from 150 to 390 bar and in the presence of a chromium-free heterogeneous catalyst comprising copper.

Abstract: Process for preparing monoethylene glycol (MEG) by metal-catalyzed reaction of a dialkyl oxalate of the formula I where R1 and R2 are each, independently of one another, methyl, ethyl, n-propyl or isopropyl, with hydrogen (H2), wherein the dialkyl oxalate (I) is used as melt or as a solution in a solvent, dialkyl oxalate (I) and H2 are used in a molar ratio of H2: dialkyl oxalate (I) in the range from 4.0 to 30 and the reaction is carried out continuously in a reactor at a cross-sectional loading of 10 m/s, a temperature in the range from 150 to 270° C., a pressure in the range from 150 to 390 bar and in the presence of a chromium-free heterogeneous catalyst comprising copper.

Abstract: Processes for preparing tetrahydrofuran and/or butane-1,4-diol and/or gamma-butyrolactone are provided, including a process for preparing tetrahydrofuran (THF) from succinic acid that has been obtained by conversion of biomass, by conversion of the succinic acid to succinic anhydride, and hydrogenation of the succinic anhydride, with removal of certain secondary components.