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A new tandem catalytic process was designed and developed as a tool for the direct conversion of the widely available feedstock 2,7-octadienol into an α,ω-diester. This innovative auto-tandem catalysis is atom efficient and consists of three consecutive palladium-catalysed reactions: ether formation, ether carbonylation and alkoxycarbonylation. By using the design of experiments (DoE) approach, significant parameters were determined and the yield of the desired α,ω-diester was optimised. Model substrates allowed deeper insight into the progress of the reaction to be gained and, as a result, the reaction sequence was uncovered. Furthermore, by simply applying other ligands, a different reaction path was followed, allowing other, new tandem catalytic sequences to be explored and enabling new compounds to be obtained.

This article describes the development of an effective thermomorphic multicomponent solvent (TMS) system for the production of branched polyamide monomers. In this system, methyl oleate, a renewable from fats and oils, and a functionalized amine are used as starting materials in a tandem catalytic reaction, which merges different reaction steps into a single preparative step. This particular TMS system consisted of a heptane/acetonitrile solvent mixture and made reusing the precious rhodium catalyst possible in three recycle runs. A constant yield of 61–65% was obtained for each run due to low‐catalyst leaching. Fortunately, the catalyst system does not require any additional phosphorous ligands and allows high yields. A scale‐up for the production of 10–11 g of the desired product in each run was realized. Subsequent hydrogenation of the product directly provided an amine ester, which is a valuable polyamide monomer. Practical applications: A method was developed to enable access to primary amines via hydroaminomethylation and hydrogenation. The product, a nitrile ester, is a valuable intermediate for polyamide monomers. This nitrile ester was successfully hydrogenated to an amine ester, which features a potential polyamide monomer directly. A catalyst recycle of the homogeneous rhodium complex within the hydroaminomethylation of methyl oleate and an amino nitrile was successfully carried out, enabling constant homogeneous catalyst activity over the course of three recycle runs. A scale‐up to obtain 10–11 g of the hydroaminomethylation product was realized. A general method is described for the conversion of methyl oleate within a hydroaminomethylation reaction. The catalyst can be recovered and reused. Valuable polyamide intermediates were obtained.

Die homogene Katalyse zeichnet sich gegenüber der heterogenen Katalyse durch höhere Selektivität und Aktivität bei gleichzeitig milderen Reaktionsbedingungen aus; die Abtrennung der teuren Übergangsmetallkatalysatoren von den Reaktionsprodukten ist jedoch schwierig. Temperaturgesteuerte Lösungsmittelsysteme, die bei geringer Temperatur in zwei Phasen vorliegen und bei Temperaturerhöhung ein homogenes, einphasiges Lösungsmittelsystem ausbilden, ermöglichen eine Reaktionsführung ohne Stofftransportlimitierungen. Durch Abkühlung bildet sich erneut ein Zweiphasensystem aus, bei dem im Idealfall eine Phase das Produkt und die andere den Katalysator enthält.

An ovel, atom efficient, orthogonal tandem catalysisw as developed yieldinga cyloin products( a -hydroxyk etones) directlyf rom olefins under hydroformylation conditions.T he combination of am etal-catalysed hydroformylation anda n organocatalysed acyloin reactionp rovides three atom efficient C À Cb ondf ormations to linear, multifunctional molecules via linkage of the intermediate n-aldehydes.A dditionally,t he rhodium catalyst system gives ah igh n/bra ratio with an exclusive conversion of the terminal doubleb ond in the hydroformylation and the n-aldehydes are converted selectively to theiracyloins.

An efficientp rotocolw as developed to prepare as erieso fd ialkylpiperazines via Rh-catalyzed bis-hydroaminomethylation of linear aliphatic alkenes with piperazine.T he well-known Rh/Biphephos catalytic system was applied, yielding the desired dialkylpiperazines within six tandemc atalytic steps,a lready at low catalyst loadings of 0.1mol%. Fort he model alkene 1-octene,g ood yields and linearities of 80% and 77:23, respectively,w ere achieved under optimized conditions.I nfluences on the catalytic system regarding n/iso ratio, possible side reactions and the reactionp ath are discussed on the basis of yield vs. time plots and parameter optimization. With the developedg eneral protocol, other linear, functionalized and branched substrates were effectively transformed to the corresponding linear N,Ndisubstituted piperazines.

Canned heat: The optimization of a tandem sequence of a metal‐catalyzed and a subsequent organocatalytic reaction is described (see figure). The tandem sequence was initially optimized toward a high yield by variations of substrate ratio, rhodium precursor, and ligands. The tandem reaction is also extendable to more complex alkenes and to substrates with additional functional groups.

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