Papers by Norman Herrmann
Chemcatchem, Oct 9, 2018
For many years, the efficient use of resources has been a major and permanent challenge for the c... more For many years, the efficient use of resources has been a major and permanent challenge for the chemical industry. The implementation of alternative resources such as renewables and carbon dioxide has been a subject of considerable discussion, but also the more efficient use of long known bulk chemicals is of great interest. Among them, 1,3-dienes such as 1,3butadiene from the C4 cut of the naphtha cracker as well as isoprene, piperylene and cyclopentadiene from the corresponding C5 section are important substrates. These dienes are presently employed in various markets, with the greatest importance being in the production of polymers and copolymers. However, homogeneous transition metal catalysis has proven to be a versatile tool to functionalize these important 1,3-dienes to low molecular weight fine chemicals by introducing, for example, nitrogen, oxygen or silicon. Hence, an upgraded use of the corresponding products as agrochemicals, pharmaceuticals, fragrances or special detergents is close at hand. The main approaches in the topic of homogeneous functionalization reactions of the industrially relevant 1,3-dienes will be summarized and discussed within the present article. Besides that, novel applications including renewable 1,3dienes, for example -myrcene and -farnesene, as well as the application of CO2 in telomerization, will be critically discussed.
Green Chemistry, 2019
An alternative strategy for the Rh-catalysed hydroformylation of technical-grade methyl oleate in... more An alternative strategy for the Rh-catalysed hydroformylation of technical-grade methyl oleate in aqueous-media has been developed.
European Journal of Lipid Science and Technology, Oct 29, 2019
The application of a so-called Jet-Loop Reactor is highly beneficial for the additive free aqueou... more The application of a so-called Jet-Loop Reactor is highly beneficial for the additive free aqueous hydroformylation of oleo chemicals. Aiming for reaction performance as well as product separation, two different approaches are presented. Decrease of co-solvent loading in case 1 as well as increase of substrate loading in case 2 favour the application of the Jet-Loop Reactor compared to a standard stirred tank reactor.
European Journal of Lipid Science and Technology, Oct 21, 2019
Green Chemistry, 2019
An alternative strategy for the Rh-catalysed hydroformylation of technical-grade methyl oleate in... more An alternative strategy for the Rh-catalysed hydroformylation of technical-grade methyl oleate in aqueous-media has been developed.
European Journal of Lipid Science and Technology, 2019
In two case studies, the reaction performance of the aqueous biphasic hydroformylation of two ind... more In two case studies, the reaction performance of the aqueous biphasic hydroformylation of two industrially relevant oleochemicals, namely methyl 10‐undecenoate (case 1) and methyl oleate (case 2), is significantly improved by the use of a Jet‐Loop Reactor concept. Based on previously reported studies, only the two green and benign co‐solvents, 1‐butanol and isopropanol are applied, respectively, in the absence of any additional auxiliary. Both reactions benefit highly from using this special piece of equipment, specifically designed for improving gas–liquid–liquid mixing to create large interfacial areas with no moving internals. In case 1, the loading of the co‐solvent 1‐butanol is successfully reduced. For the first time significant yields (>40% after 1 h) are obtained in the absence of any co‐solvent, which is very beneficial, since aldehyde products and substrate form a pure product phase enabling straightforward separation. In case 2, the loading of the substrate methyl olea...
European Journal of Lipid Science and Technology, 2019
The overall productivity of the aqueous biphasic hydroformylation of the castor oil‐derived methy... more The overall productivity of the aqueous biphasic hydroformylation of the castor oil‐derived methyl 10‐undecenoate is increased. To increase the reaction rate, the miscibility of water and the fatty compound is increased by addition of the green solvent 1‐butanol as co‐solvent. For the first time, the concentration of solvents, substrate, and product within the reaction process is experimentally examined in a biphasic system under 20 bar pressure of synthesis gas and 140 °C. A reactor to get samples of both phases is developed to determine the quarternary mixture of the reaction system presented in a four‐dimensional tetrahedron diagram. With the knowledge gained about the reaction and its drivers, it is possible to increase the efficiency of the reaction process reported so far. With simultaneously high reaction rates (turn over frequency = >5000 h−1), the space–time yield of the reaction reaches values of >120 g L−1h−1 and can be improved significantly without negatively affe...
ChemCatChem, 2018
For many years, the efficient use of resources has been a major and permanent challenge for the c... more For many years, the efficient use of resources has been a major and permanent challenge for the chemical industry. The implementation of alternative resources such as renewables and carbon dioxide has been a subject of considerable discussion, but also the more efficient use of long known bulk chemicals is of great interest. Among them, 1,3‐dienes such as 1,3‐butadiene from the C4 cut of the naphtha cracker as well as isoprene, piperylene and cyclopentadiene from the corresponding C5 section are important substrates. These dienes are presently employed in various markets, with the greatest importance being in the production of polymers and copolymers. However, homogeneous transition metal catalysis has proven to be a versatile tool to functionalize these important 1,3‐dienes to low molecular weight fine chemicals by introducing, for example, nitrogen, oxygen or silicon. Hence, an upgraded use of the corresponding products as agrochemicals, pharmaceuticals, fragrances or special dete...
ACS Sustainable Chemistry & Engineering, Jul 10, 2020
Uploads
Papers by Norman Herrmann