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Pflanzliche und tierische Öle und Fette bleiben ein wichtiger nachwachsender Rohstoff der chemischen Industrie. Ihre industrielle Nutzung hat sich in den letzten 10 Jahren von 31 auf 51 Millionen Tonnen pro Jahr erhöht. Dieser Aufsatz fasst die bedeutenden Fortschritte zusammen, die in dieser Zeit in der Oleochemie erzielt wurden, beispielsweise die Reduktion von Fettsäureestern zu Ethern, die selektive Oxidation und oxidative Spaltung von C‐C‐Doppelbindungen, die Synthese von alkylverzweigten Fettstoffen, die isomerisierende Hydroformylierung und Alkoxycarbonylierung sowie die Olefinmetathese. Auch die Nutzung von fettsäurebasierten Chemikalien in der Synthese einer Vielzahl polymerer Materialien hat stark zugenommen. Zusätzlich zu Lipasen und Phospholipasen haben mittlerweile viele weitere Enzyme in der biokatalytischen Fettchemie Anwendung gefunden. Wichtige Entwicklungen haben außerdem neue Eigenschaften bei den Ölen bestehender Nutzpflanzen hervorgebracht, was alternativ auch durch die Verwendung von metabolisch optimierten Mikroorganismen möglich ist. [ABSTRACT FROM AUTHOR]

The utilization of 5‐hydroxymethyl furfural (HMF) as a renewable feedstock for polymer synthesis has not yet been achieved as it is structurally asymmetric and contains three active functional groups. Reported here is the unprecedented step‐growth copolymerization of HMF and dihydrosilanes, through a coordination mechanism, to afford linear poly(silyl ether)s in the presence of B(C6F5)3 and the heteroscorpionate zinc hydride complex LZnH [L=(MePz)2CP(Ph)2NPh, MePz=3,5‐dimethylpyrazolyl]. The adduct B(C6F5)3⋅⋅⋅H⋅⋅⋅Zn, confirmed by NMR spectroscopy and DFT calculations, plays a key role in the synergistic catalysis, where B(C6F5)3 activates ZnH and stabilizes the Zn+ active species, and the sterically bulky ZnH effectively inhibits (C6F5)3B from reacting with dihydrosilane to form (C6F5)3B‐H‐Si, which facilely initiates ring opening of furan. The mechanism was studied by DFT simulations. [ABSTRACT FROM AUTHOR]

Coordination polymerization of renewable 3-methylenecyclopentene has been investigated for the first time using rare-earth metal-based precursors bearing various bulky ligands. All the prepared complexes catalyze controllable polymerization of 3-methylenecyclopentene into high molecular weight polymers, of which the NPN- and NSN-tridentate non-Cp ligated lutetium-based catalytic systems exhibited extremely high activities up to 11 520 kg/(molLu⋅h) in a dilute toluene solution (3.2 g/100 mL) at room temperature. The resultant polymers have pure 1,4-regioregularity (>99 %) and tailorable number average molecular weights (1-20×104) with narrow molecular weight distributions (polydispersity index (PDI)=1.45-1.79). DFT simulations were employed to study the polymerization mechanism and stereoregularity control. [ABSTRACT FROM AUTHOR]

A naturally abundant terpene, limonene (A), was radically polymerized with a maleimide derivative (B) and methacrylate (C) in a fluorinated alcohol to give terpolymers with unprecedented BAB-random-C sequences in which the BAB monomer sequence was randomly copolymerized with a C unit. In each binary system, limonene was hardly copolymerized with methacrylate while it was efficiently copolymerized with maleimide to result in a 1:2-alternating BAB periodic sequence, in part due to the penultimate effects and hydrogen-bonding interactions with fluoroalcohol. Methacrylate and maleimide were randomly copolymerized to give copolymers rich in methacrylate units with minimal amounts of maleimide-maleimide sequences. Their terpolymerization resulted in a BAB-r-C sequence as a consequence of the selective BAB polymerization between limonene and maleimide, the random copolymerization between methacrylate and maleimide, and the lack of copolymerization between limonene and methacrylate. [ABSTRACT FROM AUTHOR]

The most abundant naturally occurring terpene, α-pinene, which cannot be directly polymerized into high polymers by any polymerization method, was quantitatively converted under visible-light irradiation into pinocarvone, which possesses a reactive exo methylene group. The bicyclic vinyl ketone was quantitatively polymerized in fluoroalcohols by selective (99 %) ring-opening radical polymerization of the four-membered ring, which results in unique polymers containing chiral six-membered rings with conjugated ketone units in the main chain. These polymers display good thermal properties, optical activities, and contain reactive conjugated ketone units. Reversible addition fragmentation chain transfer (RAFT) polymerization was successfully accomplished by using appropriate trithiocarbonate RAFT agents, enabling the synthesis of thermoplastic elastomers based on controlled macromolecular architectures. [ABSTRACT FROM AUTHOR]

For hundreds of millions of years, nature uses carbon dioxide in photosynthesis as a vital building block of life. The compound is also an essential part of the carbon cycle and is co-responsible for the transport of carbon between Earth's spheres. However, over the last years CO2 has been closely associated with global warming since the immense emissions from mainly the burning of fossil resources has led to a vast increase in atmospheric CO2-levels. Therefore, not only a reduction of emissions on a global scale is crucial but also a trend towards renewable resources is clearly visible and necessary due to depleting fossil resources. In this context, the use of CO2 as an abundant resource in the chemical industry can contribute its share. [ABSTRACT FROM AUTHOR]

The production of bulk chemicals and fuels from renewable bio-based feedstocks is of significant importance for the sustainability of human society. Adipic acid, as one of the most-demanded drop-in chemicals from a bioresource, is used primarily for the large-volume production of nylon-6,6 polyamide. It is highly desirable to develop sustainable and environmentally friendly processes for the production of adipic acid from renewable feedstocks. However, currently there is no suitable bio-adipic acid synthesis process. Demonstrated herein is the highly efficient synthetic protocol for the conversion of mucic acid into adipic acid through the oxorhenium-complex-catalyzed deoxydehydration (DODH) reaction and subsequent Pt/C-catalyzed transfer hydrogenation. Quantitative yields (99 %) were achieved for the conversion of mucic acid into muconic acid and adipic acid either in separate sequences or in a one-step process. [ABSTRACT FROM AUTHOR]

Energy security presents several paradoxes including the fact that owning large energy resources may be a source of instability, while a properly managed interdependence of producer and consumer can prove stabilizing. Oil and gas wealth is already known to be linked to failings in economic development and security. Countries that seek to maximize native production from nuclear power face physical and proliferation risks, while large-scale renewable projects raise their own issues of safety and civil freedom. Interdependence based on producers' comparative advantages makes more economic sense and may also force partners to overcome international problems that would otherwise fester into something worse. [ABSTRACT FROM AUTHOR]

A brief assessment of future options for the supply of energy in the United States demonstrates that President Obama will face an extraordinary challenge in attempting to overcome the nation's long-term energy crisis. His natural inclination has been to make a series of modest gestures toward 'green energy independence'. But these have been wholly insufficient. In order to meet the energy crisis, a White House-led initiative on the scale of the Manhattan Project that produced the first atomic bomb is needed. Its principal goals should be to drastically reduce the contribution of oil and coal to energy supply in the United States, increase the contribution of renewable energy and demilitarize the reliance on imported oil. [ABSTRACT FROM AUTHOR]

Eines der häufigsten Terpene in der Natur, Limonen (A), kann in einem fluorierten Alkohol radikalisch mit Maleimid (B) und Methacrylat (C) zu Terpolymeren mit nie dagewesenen BAB‐random‐C‐Sequenzen copolymerisiert werden. In der Zuschrift auf S. 1815 ff. zeigen K. Satoh, M. Kamigaito und M. Ojika, dass die Sequenz das Ergebnis einer selektiven BAB‐Polymerisation von Limonen und Maleimid, einer fast ausschließlichen Homopolymerisation von Methacrylat während der Limonen‐Methacrylat‐Copolymerisation und einer Zufalls‐Copolymerisation von Methacrylat und Maleimid ist. [ABSTRACT FROM AUTHOR]