Preparation and Crystal Structural Study of a Novel Coordinated Polymer [HgI<Subscript>2</Subscript>(4-bped)<Subscript>2</Subscript>] (bped = bis(4-pyridyl)ethylene diamine)

Abstract  

A novel coordinated polymer [HgI₂(4-bped)₂] was synthesized through the reaction of bis(4-pyridyl)ethylene diamine and HgI₂ in mixed MeOH–THF (5:2). The crystal structural analysis indicated that the complex crystallized in a monoclinic space group P2₁/c, a = 10.8392(12), b = 19.841(2), c = 8.8279(10), β = 95.452(2), V = 1889.9(4) ?³, Z = 4. The complex possessed a novel three-dimensional supramolecular framework formed by hydrogen bonds among repeating [HgI₂(4-bped)]₂ dimeric units.     

Fungal citridone D having a novel phenylfuropyridine skeleton

Citridone D was isolated from the culture broth of Penicillium sp. FKI-1938 by solvent extraction, silica gel column chromatography and HPLC. The structure of citridone D was elucidated by spectroscopic analysis including NMR analysis. Citridone D was found to have a novel phenylfuropyridine skeleton different from those of other citridones. Citridone D potentiated miconazole activity against Candida albicans.     

Synthesis of 3-(dibromoacetyl)tropolone and its reactions with thioureas and thioamides

3-(Dibromoacetyl)tropolone ( 3 ) was obtained in the reaction of 3-acetyltropolone with two equimolar amounts of phenyltrimethylammonium tribromide. This tropolone 3 reacted with thiourea, 1-methyl-2-thiourea, and 1-phenyl-2-thiourea to afford N-unsubstituted and N-methyl- or N-phenyl-substituted 3-(2-amino-4-thiazolyl)tropolones. The reactions of 3 with thioacetamide and thiobenzamide gave 3-(2-methyl-and 2-phenyl-4-thiazolyl)tropolones.     

Palladium-catalysed asymmetric arylation of tert-cyclobutanols via enantioselective C-C bond cleavage

Palladium-catalysed arylation of tert-cyclobutanols with aryl bromide involving enantioselective C-C bond cleavage affords chiral ketones with moderate to good enantioselectivity.     

Mechanistic study on radiation-induced grafting into fluorinated polymer solid films using a swelling-induced detachment of grafted polymers

The radiation-induced graft polymerization (RGP) of styrene into poly(ethylene-co-tetrafluoroethylene) films was performed at various monomer concentrations and solvents at 60 °C. The grafted polystyrene (g-PS) was isolated using the swelling-induced detachment phenomenon, and the number-averaged molecular weight (Mn) and the number of g-PS (Np) were determined using gel permeation chromatography. The Mn increased consistently with an increase in the grafting time up to 2–3 hours, indicating very low termination rates, which was a result of the “gel effect”. This is the first direct evidence of the gradual Mn increase over time using RGP in thermally and chemically stable polymer films such as fluorinated polymers. When the Mn and Np were plotted as a function of the degree of grafting (DOG), sudden Np drops along with rapid Mn increases were observed in the DOG region of 80–90%, indicating negligible initiation and propagation; however, a recombination termination between two propagating g-PS radicals dominated the later part of the grafting process. Further increases in both Mn and Np were observed subsequently, implying that reinitiation and propagation events were triggered by morphological changes, as observed by small- and ultrasmall-angle X-ray scattering experiments, which liberated the dormant radicals from the lamellar crystals.     

Radiation-Induced Asymmetric Grafting of Different Monomers into Base Films to Prepare Novel Bipolar Membranes

We prepared novel bipolar membranes (BPMs) consisting of cation and anion exchange layers (CEL and AEL) using radiation-induced asymmetric graft polymerization (RIAGP). In this technique, graft polymers containing cation and anion exchange groups were introduced into a base film from each side. To create a clear CEL/AEL boundary, grafting reactions were performed from each surface side using two graft monomer solutions, which are immiscible in each other. Sodium p-styrenesulfonate (SSS) and acrylic acid (AA) in water were co-grafted from one side of the base ethylene-co-tetrafluoroethylene film, and chloromethyl styrene (CMS) in xylene was simultaneously grafted from the other side, and then the CMS units were quaternized to afford a BPM. The distinct SSS + AA- and CMS-grafted layers were formed owing to the immiscibility of hydrophilic SSS + AA and hydrophobic CMS monomer solutions. This is the first BPM with a clear CEL/AEL boundary prepared by RIAGP. However, in this BPM, the CEL was considerably thinner than the AEL, which may be a problem in practical applications. Then, by using different starting times of the first SSS+AA and second CMS grafting reactions, the CEL and AEL thicknesses was found to be controlled in RIAGP.     

Reactivity of polyiodide toward 1, 3-bis(4-pyridyl)propane (bpp): synthesis and structure of an organic-inorganic hybrid compound [(CuI2)2(N,N′-dimethyl-bpp)] n

The solution-phase reaction of a metal iodide with 1, 3-bis(4-pyridyl)propane (bpp) yields a new organic-inorganic hybrid framework, [(CuI2)2(N,N-dimethyl-bpp)] _n (1), which is made up of organic cations [dimethyl-bpp]²⁺ and an infinite [Cu₂I₄] _n ²⁻ anion chain; The cluster 1 obtained via the reaction between polyiodide complexes and organic N-donor ligand suggests that this simple synthetic approach is likely to be applicable to the construction of polymeric clusters.Supplementary material CCDC-253123 contains the crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; Fax: +44-1223-336-033; E-mail: deposit@ccdc.cam.ac.uk].