Dynamic Loading and Unloading of Proteins in Polymeric Stomatocytes: Formation of an Enzyme-Loaded Supramolecular Nanomotor.

Self-powered artificial nanomotors are currently attracting increased interest as mimics of biological motors but also as potential components of nanomachinery, robotics, and sensing devices. We have recently described the controlled shape transformation of polymersomes into bowl-shaped stomatocytes and the assembly of platinum-driven nanomotors. However, the platinum encapsulation inside the structures was low; only 50% of the structures contained the catalyst and required both high fuel concentrations for the propelling of the nanomotors and harsh conditions for the shape transformation.

μ-3,3'-Diisopropyl-1,1'-(propane-1,3-di-yl)bis-(1,3-diazinan-2-yl-idene)]bis-[bromido-(η(4)-cyclo-octa-1,5-diene)rhodium(I).

The title compound, [Rh2Br2(C8H12)2(C17H32N4)], was obtained by the reaction of 3,3'-(propane-1,3-di-yl)bis-(1-isopropyl-3,4,5,6-tetra-hydro-pyrimidin-1-ium) bromide and [{Rh(cod)Cl}2] (cod is cyclo-octa-1,5-diene) in tetra-hydro-furan. The two Rh(I) atoms each have a distorted square-planar coordination environment, defined by a bidentate cod ligand, a bromide anion and one C atom of the bridging bidentate bis-N-heterocyclcic carbene (NHC) ligand. The average Rh-CNHC distance is 2.

Injectable hydrogels from segmented PEG-bisurea copolymers.

We describe the preparation of an injectable, biocompatible, and elastic segmented copolymer hydrogel for biomedical applications, with segmented hydrophobic bisurea hard segments and hydrophilic PEG segments. The segmented copolymers were obtained by the step growth polymerization of amino-terminated PEG and aliphatic diisocyanate. Due to their capacity for multiple hydrogen bonding within the hydrophobic segments, these copolymers can form highly stable gels in water at low concentrations.

Ring opening metathesis polymerization-derived block copolymers bearing chelating ligands: synthesis, metal immobilization and use in hydroformylation under micellar conditions.

Norborn-5-ene-(N,N-dipyrid-2-yl)carbamide (M1) was copolymerized with exo,exo-[2-(3-ethoxycarbonyl-7-oxabicyclo[2.2.1]hept-5-en-2-carbonyloxy)ethyl]trimethylammonium iodide (M2) using the Schrock catalyst Mo(N-2,6-Me₂-C₆H₃)(CHCMe₂Ph)(OCMe(CF₃)₂)₂[Mo] to yield poly(M1-b-M2).

Ring-opening metathesis polymerization-derived, polymer-bound Cu-catalysts for click-chemistry and hydrosilylation reactions under micellar conditions.

Ring-opening metathesis polymerization has been used for the synthesis of the amphiphilic block-copolymer poly(M1-co-M3)-b-poly(M2) from the hydrophilic monomer 5-{2-[2-(2-methoxy-ethoxy)-ethoxy]-ethoxymethyl}-7-oxabicyclo[2.2.1]hept-2-ene (M2), and the hydrophobic monomers endo,exo-5-decyloxymethyl-bicyclo[2.

CO2 and Sn(II) adducts of N-heterocyclic carbenes as delayed-action catalysts for polyurethane synthesis.

Catalytic rivals: Both CO(2)-protected tetrahydropyrimidin-2-ylidene-based N-heterocyclic carbenes (NHCs) and Sn(II)-1,3-dimesitylimidazol-2-ylidene, as well as Sn(II)-1,3-dimesitylimidazolin-2-ylidene complexes (example displayed), have been identified as truly latent catalysts for polyurethane (PUR) synthesis rivaling all existing systems both in activity and latency.A series of CO(2)-protected pyrimidin-2-ylidenes as well as 1,3-dimesitylimidazol-2-ylidene and dimesitylimidazolin-2-ylidene complexes of Sn(II) have been prepared. Selected single-crystal X-ray structures are reported.