With the increasing efforts to substitute fossil resources by renewable ones, there is a strong demand for the establishment of both new basic chemicals and innovative synthesis methods. Meeting the high degree of purity needed for monomers that are used for polymer synthesis is challenging. Intelligent processing methods are necessary because available feedstocks often are mixtures of different components. Linear molecules are favored for the synthesis of high-grade polymers such as polyamides or polyesters, but applications of monomers with chain lengths beyond 13 carbons are scarce. Monoenic fatty acid derivatives might comprise a well-suited raw material base because of their preformed linear structure. The isomerization of the internal double bond to the end of the chain, which is thermodynamically unfavorable, and further selective reaction at this position to a,w-functionalized monomers seems to be the bottle neck. Only a few successful ideas have been developed so far. Behr and co-workers obtained only 36 % of the linear product in the hydroformylation of methyl oleate.[1] A more convincing concept was presented by Cole-Hamilton and co-workers.[2] The authors reported a highly selective isomerizing methoxycarbonylation of methyl oleate to dimethyl 1,19 nonadecanedioate. In the presence of CH 3 SO 3 H and a sterically strongly hindered Pd bisphosphine catalyst the double bond was shifted initially to the terminal position in the chain. This reaction step was followed by the addition of CO and the insertion of a methoxy group, which proceeded exclusively at the C18 carbon for sterical reasons. Mecking et al. [3] used this methoxycarbonylation recently for the synthesis of new polyester types.In this contribution, a more global approach is presented, involving i) catalytic reactions of high selectivity; and ii) the use of a high-oleic sunflower oil (HOSO) as a vegetable oil (1), instead of fatty esters, in a simplified one-pot procedure (Scheme 1).[4] Such processing may be advantageous for technical applications. Thus, the 1,19-diester 2 is utilized as a platform chemical for 1,19-building blocks, leading to novel polymers.During the last years, intensive studies on the methoxycarbonylation of lower olefins and of unsaturated carboxylic acids and esters have been published in the literature.[2, 3, 5] According to our investigations, the formerly used catalytic system Pd/ bis(di-tert-butylphosphinomethyl)-benzene/CH 3 SO 3 H [2] is surprisingly capable of a three-stage reaction in one batch. Consequently, 1 was converted directly into 2 via a parallel and/or subsequent sequence of transesterification/isomerization, and methoxycarbonylation.[4] The highly selective reaction towards 2 was neither affected by the formation of glycerol nor by minor components in the technical grade oil 1, such as free fatty acids (approx. 0.1 %) or unsaponifiables (approx. 1.5 % lecithin, sterols). Moreover, an up-scaling of the reaction over several orders of magnitude was possible without any significant loss in yield and sele...

Bisdithiooxalate is introduced as an outstanding new coupling agent with four reactive centers which effectively reacts with amino-terminated polyamide 12. Peculiarities of the coupling behavior are discussed on the basis of a kinetic model.

Direct functionalization of C(sp3)–H bonds allows rapid access to valuable products, starting from simple petrochemicals. However, the chemical transformation of non-activated methylene groups remains challenging for organic synthesis. Here, we report a general electrochemical method for the oxidation of C(sp3)–H and C(sp2)–H bonds, in which cyclic alkanes and (cyclic) olefins are converted into cycloaliphatic ketones as well as aliphatic (di)carboxylic acids. This resource-friendly method is based on nitrate salts in a dual role as anodic mediator and supporting electrolyte, which can be recovered and recycled. Reducing molecular oxygen as a cathodic counter reaction leads to efficient convergent use of both electrode reactions. By avoiding transition metals and chemical oxidizers, this protocol represents a sustainable oxo-functionalization method, leading to a valuable contribution for the sustainable conversion of petrochemical feedstocks into synthetically usable fine chemicals and commodities.

Synthesis of PEi-g-PA12 with concentration of PEi 2-40 wt % was fulfilled in two different ways, as ring-opening polymerization of LL and transamidation of linear PA12 in the presence of core PEi molecules. Both methods provide almost uniform materials. Obtained samples were characterized using different techniques: solution and melt viscosity, molecular weight and molecular weight distribution of star polymers and PA12 "arms" with different content of cores, as well as melt and glass transition measurements, were fulfilled. For clarification of PEi-g-PA12 structure and mechanism of grafting, bis-(hexamethylen)triamin and tris(2-aminoethyl)amin were used as a model core molecules. Participation of not only the primary but also the secondary and tertiary amino groups in the formation of PEi-g-PA12 polymers (until 2-8 wt % of PEi content) have been established. At higher content of PEi (8 -15 wt %), only primary amino groups of core molecules take part in grafting.

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