Abstract:
The present invention relates to a method for isomerizing a 3-(Z)-unsaturated carboxylic acid of the formula 1-Z or a salt thereof, wherein R2 is C1-C24-alkyl, C2-C24-alkenyl having 1, 2, 3 or more than 3 C—C double bonds, unsubstituted or substituted C5-C12-cycloalkyl, or unsubstituted or substituted aryl; R1 is hydrogen or has one of the definitions specified for R2; with the proviso that R2 has a higher priority than R1 in accordance with IUPAC; to give a 3-(E)-unsaturated carboxylic acid of the formula I-E or a salt thereof, wherein the isomerization of the compound of the formula 1-Z is effected in the presence of an anhydride of an organic acid and a base or in the presence of a ketene of formula CR11R12C(0), wherein R11 and R12 are as defined in the claims and in the specification and a base. In particular, the present invention relates to a method for preparing compositions with increased content of (3E,7E)-homofarnesylic acid starting from compositions comprising (3Z,7E)- and (3E,7E)-homofarnesylic acid.
Abstract:
The invention relates to a process for preparing primary amines by alcohol amination of alcohols with ammonia with the elimination of water, where the alcohol amination is carried out under homogeneous catalysis in the presence of at least one complex catalyst which comprises ruthenium and at least one at least bidental donor ligand, but no anionic ligands.
Abstract:
A method for hydrogenating an ester of the general formula (III)
with molecular hydrogen to give the alcohols
at a temperature of 50 to 200° C. and a pressure of 0.1 to 20 MPa abs in the presence of a manganese(I) complex, in which the manganese complex comprises a tridentate ligand L with the general formula (II)
Abstract:
Method for hydrogenating an ester with molecular hydrogen to the corresponding alcohols in the presence of a ruthenium complex (I), wherein said complex comprises a tridentate ligand L of the general formula (II) n and m are each independently 0 or 1, and the solid-dashed double lines represent a single or double bond, with the proviso that in the case of n=1 both solid-dashed double lines represent a single bond and m is 1, and in the case of n=0 one solid-dashed double line represents a single bond and the other solid-dashed double line represents a double bond, wherein in the case of a double bond on the side facing the phenyl ring m=1, in the case of a double bond on the side facing the pyridyl ring m=0, or both solid-dashed double lines represent a single bond and m is 1.
Abstract:
A process for performing a continuous gas/liquid biphasic high-pressure reaction, wherein a gas and a liquid are introduced into a backmixed zone of a reactor and in the backmixed zone the gas is dispersed in the liquid by stirring, injection of gas and/or a liquid jet, a reaction mixture consecutively traverses the backmixed zone and a zone of limited backmixing, and a liquid reaction product is withdrawn at a reaction product outlet of the zone of limited backmixing, wherein the reactor comprises: an interior formed by a cylindrical vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by means of internals into the backmixed zone, the zone of limited backmixing and a cavity, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor and which delimits the zone of limited backmixing from the backmixed zone, backmixing-preventing second internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing and a third internal element which in the interior extends in the longitudinal direction of the reactor and is open at the bottom, wherein the third internal element forms the cavity in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume. The reaction volume of the reactor used in the process can be reversibly reduced in simple fashion. The invention further relates to a process for adapting the reaction volume of a reactor suitable for performing a gas/liquid biphasic high-pressure reaction having an outlet for a liquid reaction product in which an internal element is arranged so as to form a cavity open at the bottom in which gas bubbles collect and do not escape upwards, thus preventing the volume of the cavity from being occupied by liquid and reducing the reaction volume.
Abstract:
A reactor for performing a reaction between two immiscible fluids of different density, comprising an interior formed by a cylindrical, vertically oriented elongate shell, a bottom and a cap, wherein the interior is divided by internals into a backmixed zone, a zone of limited backmixing preferably arranged below the backmixed zone and a plug-flow zone which are at least consecutively traversable by one of the fluids, wherein the backmixed zone comprises at least one inlet and the plug-flow zone comprises an outlet and the backmixed zone comprises at least one mixing apparatus selected from a stirrer, a jet nozzle and means for injecting the fluid of lower density, a first cylindrical internal element which in the interior extends in the longitudinal direction of the reactor, which delimits the zone of limited backmixing from the plug-flow zone and which comprises a first passage to the backmixed zone and a second passage to the plug-flow zone, a second internal element which delimits the backmixed zone from the plug-flow zone such that there is no direct fluid connection between the backmixed zone and the plug-flow zone, and backmixing-preventing third internal elements in the form of random packings, structured packings or liquid-permeable trays arranged in the zone of limited backmixing. The reactor allows an optimal residence time distribution in the reaction of the two immiscible fluids of different density. The invention further relates to a process for performing a continuous reaction in the reactor.
Abstract:
The present invention relates to a process for the preparation of an optically active carbonyl compound by asymmetric hydrogenation of a prochiral α,β-unsaturated carbonyl compound with hydrogen in the presence of at least one optically active transition metal catalyst that is soluble in the reaction mixture and which has rhodium as catalytically active transition metal and a chiral, bidentate bisphosphine ligand, wherein the reaction mixture during the hydrogenation of the prochiral α,β-unsaturated carbonyl compound additionally comprises at least one compound of the general formula (I): in which R1, R2: are identical or different and are C6- to C10-aryl which is unsubstituted or carries one or more, e.g. 1, 2, 3, 4 or 5, substituents which are selected from C1- to C6-alkyl, C3- to C6-cycloalkyl, C6- to C10-aryl, C1- to C6-alkoxy and amino; Z is a group CHR3R4 or aryl which is unsubstituted or carries one or more, e.g. 1, 2, 3, 4 or 5, substituents which are selected from C1- to C6-alkyl, C3- to C6-cycloalkyl, C6- to C10-aryl, C1- to C6-alkoxy and amino, wherein R3 and R4 are as defined in the claims and the description.