Stereospecific polymerizations of functionalized acetylenes were successfully performed using a Rh complex as the catalyst and triethylamine as a base yielding poly(3,4,5‐tridodecyloxyphenylacetylene) (Poly5) and poly[3,4,5‐tris((S)‐3,7‐dimethyloctyloxy)phenylacetylene] (Poly6). Poly5 and Poly6 are liquid crystalline with presumably a bilayer‐type architecture in which the mesogens are arranged in an antiparallel overlapping interdigitated manner. Poly6 showed unusual thermal stereomutation in solution in a very narrow temperature range.

Two novel chiral (bola)amphiphilic oligo( p-phenylenevinylene)s (OPVs) have been synthesised and fully characterised. Decoration of the hydrophobic OPV backbone with a hydrophilic tris[tetra(ethylene oxide)]benzene wedge on one side and a hydrophobic tris(alkoxy)benzene wedge on the other side, resulted in amphiphilic OPV1. In bolaamphiphile OPV2, two hydrophilic tris[tetra(ethylene oxide)]benzene wedges are connected at both ends of the OPV backbone. The organisation of the amphiphiles has been investigated at the air-water interface and in water. Langmuir monolayers of OPV1 showed that these amphiphiles are perpendicularly oriented at the air-water interface. In the case of OPV2, the OPV units are lying flat on the subphase with the hydrophilic ethylene glycol wedges pointing into the water phase. In chloroform, the OPV derivatives are present as molecularly dissolved species. In water, the amphiphilic OPV derivatives aggregate in chiral stacks, as can be concluded from UV-vis, fluorescence and CD spectroscopy. Temperature dependent measurements showed for OPV1 a transition at 50 ЊC from a chiral aggregated state to disordered aggregates. In the case of bolaamphiphilic OPV2, the transition at 55 ЊC between those states is a less cooperative process. The chiral order in the assemblies of the bolaamphiphiles can be influenced by the addition of salt.

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Polymerization of a functionalized acetylene was successfully performed using a Rh complex as the catalyst and triethylamine as a base yielding poly{(E,E,E)‐4‐[4‐[4‐(3,4,5‐tridodecyloxystyryl)‐2,5‐bis((S)‐2‐methylbutoxy)styryl]‐2,5‐bis((S)‐2‐methylbutoxy)styryl]phenylacetylene} (PAOPV). Films of PAOPV mixed with a fullerene derivative showed electron transfer from the OPV oligomer donor to the fullerene acceptor. The films could be furthermore used in photovoltaic devices.

Analyte-matrix adducts are normally absent under typical matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) conditions. Interestingly, though, in the analysis of several types of organic compounds synthesized in our laboratory, analyte-matrix adduct ion peaks were always recorded when common MALDI matrices such as 4-hydroxy-α-cyanocinnamic acid (CHCA) were used. These compounds are mainly those with a benzene-1,3,5-tricarboxamide (BTA) or urea moiety, which are important building blocks to make new functional supramolecular materials. The possible mechanism of the adduct formation was investigated. A shared feature of the compounds studied is that they can form intermolecular hydrogen bonding with matrices like CHCA. The intermolecular hydrogen bonding will make the association between analyte ions and matrix molecules stronger. As a result, the analyte ions and matrix molecules in MALDI clusters will become more difficult to be separated from each other. Furthermore, it was found that analyte ions were mainly adducted with matrix salts, which is probably due to the much lower volatility of the salts compared with that of their corresponding matrix acids. It seems that the analyte-matrix adduct formation for our compounds are caused by the incomplete evaporation of matrix molecules from the MALDI clusters because of the combined effects of enhanced intermolecular interaction between analyte-matrix and of the low volatility of matrix salts. Based on these findings, strategies to suppress the analyte-matrix adduction are briefly discussed. In return, the positive results of using these strategies support the proposed mechanism of the analyte-matrix adduct formation.

An oligothiophene/chiral oligo(ethyleneoxy) block copolymer (PolyT6) has been synthesized in which a sexithiophene block alternates with a well-defined chiral undeca(ethyleneoxy) block. The polymer shows good solubility in chloroform, and ultraviolet-visible studies in this solvent reveal a spectrum similar to that of the chirally substituted monomeric sexithiophene (T6) analogue. The aggregation of PolyT6 occurs in dioxane; however, no helicity is present in this aggregate, in contrast to aggregated T6. This behavior illustrates that although the processability and mechanical robustness of block copolymers may be superior to those of analogous oligomers, the degree of self-assembled order found in oligomer-based systems may be lost in the polymers.

Wittig‐ Reaktion der Phosphoniumbromide (I) mit dem Aldehyd (VI) (Darstellung beschrieben) gibt ein Gemisch der trans/cis‐isomeren Retinylacetate (II) und (III), aus dem die Trideutero‐l 1‐cis‐retinaIe (V) bzw. ihre all‐trans‐trans‐Isomeren (IV) erhältlich sind.

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