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This paper describes the synthesis and characterization of a new class of amphiphilic, water-soluble diblock copolymers based on 2oxazoline derivatives with pendent (2S,4S)-4-diphenylphosphino-2-(diphenylphosphinomethyl)pyrrolidine (PPM) units in the hydrophobic block. The synthetic strategy involves the preparation of a diblock copolymer precursor with ester functionalities in the side chain; which were converted into carboxylic acids in a polymer-analogous step and finally reacted with the PPM ligand. The structures of the copolymers were characterized by (1)H and (31)P NMR spectroscopy and GPC measurements. Subsequently, these polymers were successfully utilized as a polymeric support for the asymmetric hydrogenation of 1) (Z)-alpha-acetamido cinnamic acid and 2) methyl (Z)-alpha-acetamido cinnamate in water, showing 90 % substrate conversion at 25 degrees C within 20 minutes at atmospheric H(2) pressure (1 bar) for methyl (Z)-alpha-acetamido cinnamate.

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We present the first synthesis of an Nheterocyclic carbene (NHC) rhodium catalyst immobilized to an amphiphilic, water-soluble block copolymer support. The resulting macroligand was applied in the hydroformylation of 1-octene under aqueous two-phase conditions in four consecutive cycles and showed high activity up to 2360 h -1 (TOF).

A series of heptadiynes was cyclopolymerized by Schrock initiators to produce poly(ene)s exclusively based on one single repetitive unit, i.e. 1,2‐cyclopent‐2‐enylenvinylenes. Polymers containing virtually solely 1,2‐cyclopent‐2‐enylenvinylene units were obtained by various routes, e.g. by low‐temperature‐initiated cyclopolymerization of diethyldipropargyl malonate (DEDPM). A chiral poly(ene) was prepared from 4‐(ethoxycarbonyl)‐4‐(1S, 2R, 5S)‐(+)‐menthoxycarbonyl‐1,6‐heptadiyne (ECMHD) to determine the configuration of the double bonds and the tacticity of the poly(ene) backbone. Poly(ECMHD) consisted of >96% 5‐membered rings and possessed a tactic, alternating cis‐trans structure. Alternatively, poly(DEDPM) exclusively based on 1,2‐(cyclopent‐1‐enylene)vinylene units was prepared using MoCl5‐n‐Bu4Sn‐EtOH‐quinuclidine (1:1:5:1) and MoOCl4‐n‐Bu4Sn‐EtOH‐quinuclidine (1:1:2:1). The initiator efficiency of MoOCl4‐n‐Bu4Sn‐EtOH‐quinuclidine (1:1:2:1) was as high as 91%, the highest value ever reported for such systems. Multistage polymerizations of DEDPM indicated for both initiator systems that the catalytic species were active for at least 6 hours in the presence of monomer yet did not fulfill the criteria of a truly living polymerization. Finally, a new modification of the Grubbs‐Hoveyda catalyst, Ru(CF3COO)2(CH‐2‐(2,4,5‐(MeO)3‐C6H3)(SIMes) (SIMes=1,3‐dimesityl‐4,5‐dihydroimidazol‐2‐ylidene) allowed the first ruthenium alkylidene‐catalyzed living cyclopolymerization of DEDPM. The different initiators, their properties, the resulting polymerization systems as well as the physical properties of the resulting poly(ene)s are summarized.