Herein, we report results on olefin self-metathesis in the presence of low catalyst loadings as an efficient approach for the synthesis of a,v-difunctional monomers from plant oils containing a high ratio of polyunsaturated fatty acids. It was clearly observed that the driving force for the synthesis of the C18diester was the formation of cyclohexa-1,4-diene and hex-3-ene, both of which, in contrast to selfmetathesis of oleic acid methyl ester, can easily be removed from the reaction mixture by distillation and thus help to shift the metathesis equilibrium to full conversion. The resulting unsaturated C18-diester was hydrogenated and subsequently converted to the corresponding diol. Both monomers were used for the synthesis of a long-chain polyester in the presence of 1,5,7-triazobicyclodecane (TBD) as a catalyst. The molecular weight of the resulting polymer was determined by static light scattering. Moreover, DSC analysis was applied to determine the thermal properties of the final polymer.

The templated self-assembly of two different chromophores attached to the same binding motif gives oligomers of statistical mixtures without any control on the resulting chromophore sequence. The first self-assembled bichromophore system is reported, in which the resulting chromophore sequence is simply governed by the DNA template. A new ethynylpyrene-diaminopurine 2'-deoxynucleoside was combined with the ethynyl nile red-modified 2'-deoxyuridine to achieve this completely programmable sequence selective self-assembly. The helical ordering of the two different chromophores by DNA templates with different mixtures of A-T sequences yields precise control over the optical properties of the formed assemblies, which was proven by methods of optical spectroscopy.

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In this study, we take advantage of the a-CH-acidity of fatty acid esters in order to obtain a-arylated fatty acid derivatives. Therefore, fatty acid tert-butyl esters were deprotonated with strong bases, for instance lithium bis(trimethylsilyl)amide, and subsequently coupled with bromobenzene by palladium-Nheterocyclic carbene (NHC) catalysts. Furthermore, we tested the arylation activity of fatty acid tertbutyl esters towards 1,4-dibromobenzene in order to synthesize aryl-bridged diesters. These diesters were obtained in good yields of 60-80%.

Three dibenzothienylethenes that carry a methyl, a trifluoromethyl, or a fluoro substituent in the 2- and 2′-position were synthesised in short multistep syntheses, respectively. The trifluoromethyl and fluoromethyl substituents significantly improve the absorption properties of the corresponding open and closed isomers (both in the UV-A and in the visible range). The increasing electron deficiency (i) enlarges the portion of the closed and coloured diarylethene isomer in the corresponding photostationary states and slows down the closing and opening isomerisation, (ii) the switching reactions, both closing and opening, are slowed down, and (iii) the switching quantum yields are lowered.