The role of added water in the ionothermal synthesis of microporous aluminium phosphates

Water plays an important role in ionothermal synthesis and it has been suggested that it can influence phase selection. We have carried out an extensive study to determine the phases produced at various ratios of water to ionic liquid in the microwave assisted ionothermal synthesis of fluorinated aluminium phosphate frameworks using 1-ethyl-3-methylimidazolium bromide and 1-ethylpyridinium bromide. Aluminophosphate chabazite is the main product under ionothermal conditions while at increased levels of water the ionic liquids appear to be poor templates with dense phases predominating. The low synthesis pressure in ionothermal reactions is demonstrated and the role of template breakdown in phase selection is also discussed.     

Atom transfer radical polymerization of cyclohexyl methacrylate at a low temperature

The atom transfer radical polymerization of cyclohexyl methacrylate (CHMA) is reported. Controlled polymerizations were performed with the CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine catalytic system with ethyl 2‐bromoisobutyrate as the initiator in bulk and different solvents (25 vol %) at 40 °C. The polymerization of CHMA in bulk resulted in a controlled polymerization, although the concentration of active species was relatively elevated. The addition of a solvent was necessary to reduce the polymerization rate, which was dependent on the dipole moment. Well‐controlled polymers were obtained in toluene, diphenyl ether, and benzonitrile solutions. Poly(cyclohexyl methacrylate) as a macroinitiator was used to synthesize the poly(cyclohexyl methacrylate)‐b‐poly(tert‐butyl methacrylate) block copolymer, which allowed a demonstration of its living character. In addition, two difunctional initiators, 1,4‐bis(bromoisobutyryloxy) benzene and 1,2‐bis(bromoisobutyryloxy) ethane, were used to initiate the atom transfer radical polymerization of CHMA. The experimental molecular weights of the obtained polymers were very close to the theoretical ones. These, along with the relative narrow molecular weight distributions, indicated that the polymerization was living and controlled. For confirmation, two different poly(tert‐butyl methacrylate)‐b‐poly(cyclohexyl methacrylate)‐b‐poly(tert‐butyl methacrylate) triblock copolymers were also synthesized. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 71–77, 2005     

Eine quantitative Bestimmung des Cumarins und der Melilots?ure im Melilotus officinalis

Ohne Zusammenfassung     

Poly(vinylpyrrolidone)‐based films grown on copper surfaces

The influence of molecular weight and the amount of the poly(vinylpyrrolidone) (PVP) on the growth of poly(vinylpyrrolidone)–based films on copper surfaces was studied by electrochemical, infrared and electronic spectroscopy, and thermogravimetric methods. Complex polymer/metal ions were deposited onto a copper surface, as the result of the electrochemically generated reaction of copper cations with PVP and SCN^?, in sulfuric acid media. Spontaneous film growth on copper surfaces was generated and characterized as a Cu(II)/PVP/SCN^? complex. Infrared spectra and thermal gravimetric curves of the films generated at + 0.7 V were compared with the chemically synthesized complex, and show the same patterns. The oxidation process can be described as: Cu(0)→Cu(I) and Cu(I)→Cu(II), and the copper complex formed at more positive potentials was characterized as Cu(II)/PVP/SCN^?, with copper bonded to the oxygen atom of PVP and thiocyanate ligand N‐linked. This study focuses on the complex formation on a copper surface in acid media and its characterization through electrochemical and spontaneously generated reactions. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2206–2214, 2009     

A type 2 Ferrier rearrangement-based synthesis of d-myo-inositol 1,4,5-trisphosphate

The synthesis of d-myo-inositol 1,4,5-trisphosphate (InsP₃) from methyl α-d-glucopyranose, via a type 2 Ferrier rearrangement is reported. A key intermediate in this synthesis possesses orthogonal protecting groups at the 1-, 4- and 5-position, making it a versatile starting point for the synthesis of unnatural InsP₃ derivatives. Biological evaluation of the synthetic InsP₃ demonstrates that this compound evokes selective Ca²⁺ release via activation of InsP₃ receptors.     

Functional Interdependence in Coupled Dissipative Structures: Physical Foundations of Biological Coordination

Coordination within and between organisms is one of the most complex abilities of living systems, requiring the concerted regulation of many physiological constituents, and this complexity can be particularly difficult to explain by appealing to physics. A valuable framework for understanding biological coordination is the coordinative structure, a self-organized assembly of physiological elements that collectively performs a specific function. Coordinative structures are characterized by three properties: (1) multiple coupled components, (2) soft-assembly, and (3) functional organization. Coordinative structures have been hypothesized to be specific instantiations of dissipative structures, non-equilibrium, self-organized, physical systems exhibiting complex pattern formation in structure and behaviors. We pursued this hypothesis by testing for these three properties of coordinative structures in an electrically-driven dissipative structure. Our system demonstrates dynamic reorganization in response to functional perturbation, a behavior of coordinative structures called reciprocal compensation. Reciprocal compensation is corroborated by a dynamical systems model of the underlying physics. This coordinated activity of the system appears to derive from the system’s intrinsic end-directed behavior to maximize the rate of entropy production. The paper includes three primary components: (1) empirical data on emergent coordinated phenomena in a physical system, (2) computational simulations of this physical system, and (3) theoretical evaluation of the empirical and simulated results in the context of physics and the life sciences. This study reveals similarities between an electrically-driven dissipative structure that exhibits end-directed behavior and the goal-oriented behaviors of more complex living systems.