Rhodium-catalyzed cleavage reaction of aryl methyl ethers with thioesters

A rhodium complex catalyzed the reaction of aryl methyl ethers and thioesters giving the corresponding aryl esters and methyl sulfides. S-(p-Chlorophenyl) p-(dimethylamino)benzothioate was used for the reaction of methyl aryl ethers with electron-withdrawing groups, and an S-(p-tolyl) derivative was used for those with electron-donating groups. Polymethoxybenzenes were converted to the esters in a regioselective manner.     

A light-induced phase exhibiting slow magnetic relaxation in a cyanide-bridged [Fe4Co2] complex

Single-molecule magnets: A cyanide-bridged hexanuclear complex showed a thermal electron-transfer-coupled spin transition centered at 220?K. Light irradiation at low temperature (LT; HT = high temperature) generated a metastable state showing slow magnetic relaxation in measurements of the alternating-current magnetic susceptibility (χ(m); see picture).     

Temperature dependence of one-dimensional hydrogen bonding in morpholinium hydrogen chloranilate studied by (35)Cl nuclear quadrupole resonance and multi-temperature X-ray diffraction

The temperature dependence of (35)Cl NQR frequencies and the spin-lattice relaxation times T(1) has been measured in the wide temperature range of 4.2-420 K for morpholinium hydrogen chloranilate in which a one-dimensional O-HO hydrogen-bonded molecular chain of hydrogen chloranilate ions is formed. An anomalous temperature dependence of the NQR frequencies was analyzed to deduce a drastic temperature variation of the electronic state of the hydrogen-bonded molecular chain. The hydrogen atom distribution in the OHO hydrogen bond is discussed from the results of NQR as well as multi-temperature X-ray diffraction. Above ca. 330 K, the T(1) showed a steep decrease with an activation energy of ca. 70 kJ mol(-1) and with an isotope ratio (37)Cl T(1)/(35)Cl T(1) = 0.97 ± 0.2. The orientational change of the z axis of electric field gradient tensor in conjunction with the hydrogen transfer between adjacent hydrogen chloranilate ions is suggested as a possible relaxation mechanism.     

A Rational Repeating Template Method for Synthesis of 2 D Hexagonally Ordered Mesoporous Precious Metals

A repeating template method is presented for the synthesis of mesoporous metals with 2D hexagonal mesostructures. First, a silica replica (i.e., silica nanorods arranged periodically) is prepared by using 2D hexagonally ordered mesoporous carbon as the template. After that, the obtained silica replica is used as the second template for the preparation of mesoporous ruthenium. After the ruthenium species are introduced into the silica replica, the ruthenium species are then reduced by a vapor‐infiltration method by using the reducing agent dimethylamine borane. After the ruthenium deposition, the silica is chemically removed. Analysis by transmission and scanning electron microscopies, a nitrogen‐adsorption–desorption isotherm, and small‐angle X‐ray scattering revealed that the mesoporous ruthenium had a 2D hexagonal mesostructure, although the mesostructural ordering is decreased compared to that of the original mesoporous carbon template. This method is widely applicable to other metal systems. By changing the metal species introduced into the silica replica, several mesoporous metals (palladium and platinum) can be synthesized. Ordered mesoporous ruthenium and palladium, which are not easily attainable by the soft‐templating methods, can be prepared. This study has overcome the composition variation limitations of the soft‐templating method.     

Spin-crossover behavior and electrical conduction property in iron(II) complexes with tetrathiafulvalene moieties

Iron(II) complexes with neutral and oxidized tetrathiafulvalene (TTF) moieties were prepared and X-ray crystallographic analyses, magnetic and electrical resistivity measurements suggested an interaction of spin transition and electrical conductivity.     

Platinadithiolene-conjugated pyrylium salt with strong intramolecular donor-acceptor interaction

Protonation of a new platinum complex, Pt(1-pdtAq)((t)Bu(2)bpy), where 1-pdtAq is 1-(phenyldithiolenethynyl)anthraquinone, afforded a cyclized structure, [Pt(1-pdtPyl)((t)Bu(2)bpy)](+), with a unique electronic structure due to intense intramolecular charge transfer.     

Viscoelastic properties of poly(methyl methacrylate) with high glass transition temperature by lithium salt addition

The effect of ion‐dipole interaction between lithium cations and oxygen atoms in poly(methyl methacrylate) (PMMA), which leads to the great enhancement of glass transition temperature (T_g), on the linear viscoelastic properties is studied using binary blends of PMMA and lithium trifluoromethanesulfonate (LiCF₃SO₃). The strong interaction at low temperature leads to the high modulus in the glassy region even near T_g. The interaction becomes weak as increasing the temperature. Consequently, the rheological terminal region is clearly detected without a marked enhancement of steady‐state compliance, although the zero‐shear viscosity increases by the LiCF₃SO₃ addition. The result indicates that the crosslinking due to the ion‐dipole interaction has a lifetime that decides the longest relaxation time. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2388–2394     

Fabrication of defocus graded-index optical waveguide for evanescent wave optical amplifier

This is the first report on an evanescent wave optical amplifier with a plastic waveguide that can amplify a CW signal transmitted by a plastic optical fiber. The waveguide with a concave refractive index distribution was fabricated by an interfacial-gel polymerization technique. Since the waveguide increases the number of reflections at the boundary surface of the waveguide and the laser dye solution, the enhancement of amplification efficiency can be realized. The function of the fabricated waveguide was confirmed by calculations and experiments. The obtained results indicate that the fabricated fiber generated a larger evanescent field than the waveguide without a refractive index distribution.     

Benzo[e]pyrene skeleton dipyrylium dication with a strong donor-acceptor-donor interaction, and its two-electron reduced molecule

The donor-acceptor-donor (D-A-D) conjugated molecules 1,4-bis(diarylaminophenylethynyl)anthraquinone (1,4-Am(2)Aq) and 1,4-bis(ferrocenylethynyl)anthraquinone (1,4-Fc(2)Aq), undergo a double proton cyclization reaction with bis(trifluoromethanesulfone)imide acid (TFSIH) to yield 1,4-bis(diarylaminophenyl or ferrocenyl) dipyrylium salts [1,4-R(2)Pyl(2)](TFSI)(2) (R=Am or Fc) with novel planar pentacyclic structures similar to the aromatic benzo[e]pyrene-type skeleton. [1,4-Am(2)Pyl(2)](TFSI)(2) could be reduced to give the neutral molecule [1,4-Am(2)Pyl(2)](0), which is stable and maintains the benzo[e]pyrene-type skeleton. To the best of our knowledge, this is the first oxygen-atom-containing polycyclic aromatic hydrocarbon with 22 (4n+2) π-electrons. The obtained condensed-ring benzo[e]pyrene-type skeleton compounds show physical and chemical properties that are significantly different from those of [1,5-Am(2)Pyl(2)](TFSI)(2), which has a perylene-type skeleton.     

Shave-Off Depth Profiling for Nano-Devices

Shave-off depth profiling completely differs from ultra shallow depth profiling and has an absolute depth scale and a 50 μm wide dynamic range. In this paper we report on shave-off depth profiling of a nano-device with a complex nano-structure consisting of dynamic random access memory and introduces an analytical tool for advancing of nano-devices.