Enzymes covalently immobilized on highly porous materials are demonstrated to have very high biocatalytic activity and good recyclability, exemplified by Candida antarctica Lipase B (CAL‐B). Polymerized high internal phase emulsions (PolyHIPEs, see figure) are developed for covalent grafting of proteins (enzymes) via the reaction of the protein surface lysine residues with active ester moieties in the monolithic material.

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Virus particles are probably the most precisely defined nanometre-sized objects that can be formed by protein self-assembly. Although their natural function is the storage and transport of genetic material, they have more recently been applied as scaffolds for mineralization and as containers for the encapsulation of inorganic compounds. The reproductive power of viruses has been used to develop versatile analytical methods, such as phage display, for the selection and identification of (bio)active compounds. To date, the combined use of self-assembly and reproduction has not been used for the construction of catalytic systems. Here we describe a self-assembled system based on a plant virus that has its coat protein genetically modified to provide it with a lipase enzyme. Using single-object and bulk catalytic studies, we prove that the virus-anchored lipase molecules are catalytically active. This anchored biocatalyst, unlike man-made supported catalysts, has the capability to reproduce itself in vivo, generating many independent catalytically active copies.

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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.

This paper describes the synthesis and characterization of a new class of amphiphilic, water-soluble diblock copolymers based on 2-oxazoline derivatives with pendent N-heterocyclic carbene/palladium catalysts in the hydrophobic block. The synthetic strategy involves a four-step synthesis of three functionalized monomers, each composed of a bis(imidazoline-2-ylidene)palladium(II) diiodide derivative that is covalently linked to a 2-oxazoline monomer via a flexible alkyl spacer (alkyl = butyl, hexyl, octyl). The structure of the monomers was analyzed by 1H and 13C NMR spectroscopy, MALDI-TOF, and elemental analysis. Three diblock copolymers P1−P 3 with the monomers being part of the hydrophobic block were prepared by living cationic ring-opening polymerization. The structure and composition of the polymers was characterized by 1H and 13C NMR spectroscopy as well as GPC measurements and indicated rather low PDI of 1.3 and about 65% incorporation of the N-heterocyclic carbene/palladium-functionalized monomer into the polymer. Dynamic light scattering measurements of the polymers P1−P3 in water revealed aggregate formation with a hydrodynamic radius of 10−30 nm with high polydispersity as visualized by TEM micrographs. Subsequently, polymers P1−P3 were successfully utilized as a polymeric support for the Heck coupling of iodobenzene with styrene as a model reaction in water, showing high activities with turnover frequencies (TOF) up to 570 h-1 at 90 °C.

CoIII(salen) complexes have been immobilized on amphiphilic block copolymers, which self‐assemble in water to give micellar aggregates with a hydrophobic Co(salen) core and a water‐soluble shell (see picture). These aggregates were used to catalyze the hydrolytic kinetic resolution (HKR) of racemic aromatic epoxides over four consecutive cycles and gave the epoxides in up to 99 % ee. H2salen=N,N′‐bis(salicylidene)ethylenediamine.