Regioselective anodic monofluorination of aryl 2,2,2-trifluoroethyl sulfides gave, exclusively, aryl 1,2,2,2tetrafluoroethyl sulfides, the products of fluorination at the position « to the trifluoromethyl group. The a-monofluorination of sulfides bearing electron-withdrawing substituents other than trifluoromethyl was also successful. Furthermore, the procedure could be applied to the «,«-

Highly regioselective anodic monofluorination of various aryl and alkyl fluoroalkyl sulfides was successfully carried out, and fluorine was exclusively (aryl sulfides) or preferentially (alkyl sulfides) introduced at the position a to the fluoroalkyl group. Even simple alkyl phenyl sulfides devoid of an electron-withdrawing group could be anodically monofluorinated in satisfactory yields for the first time when etheral solvents were used as an electrolytic solution. A unique Pummerer-type mechanism via fluorosulfonium ions was proposed for this anodic fluorination by comparison with anodic -methoxylation previously studied.

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Articles you may be interested inField electron emission properties from zinc oxide nanostructures AIP Conf. Proc. 1502, 426 (2012); 10.1063/1.4769161 Three-dimensional shapes and distribution of FePd nanoparticles observed by electron tomography using highangle annular dark-field scanning transmission electron microscopy Fabrication of Mn-doped ZnO diluted magnetic semiconductor nanostructures by chemical vapor deposition J. Appl. Phys. 99, 08M119 (2006); 10.1063/1.2173235Fabrication and characterization of solid-state nanopores using a field emission scanning electron microscope Electron beam induced chemical vapor deposition ͑EBI-CVD͒ is one of the promising methods for nanofabrication. EBI-CVD has generally been carried out in conventional scanning electron microscopes and the minimum size of the deposits was in the range between 20 and 300 nm. In this study, a field emission gun scanning electron microscope ͑FE-SEM͒ and a field emission gun transmission electron microscope ͑FE-TEM͒ with gas introduction systems were employed for deposition using a W͑CO͒ 6 precursor in order to reduce the size of deposits. Dots, 15-20 nm in diameter, were produced using the FE-SEM. The dots consist mainly of tungsten with small amounts of carbon and oxygen. By using the FE-TEM, the diameter of the dots can be reduced to 3.5 nm. The relationship between probe size and dot diameter is discussed. Rods, the diameter of which was 8 nm, were also fabricated by scanning the beam position in the FE-TEM. Deposits produced by FE-TEM are smaller than those by conventional electron microscopes.

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A new type of fatigue testing machine for micro-sized specimens for MEMS applications has been developed. This fatigue testing machine consists of a magnetostrictive actuator which is able to impart small displacements to a specimen upto 20 νm with resolution of 5 nm. The actuator is connected to a metal shaft and a diamond tip of 5 νm in radius is attached to the end of the shaft. Small displacements are applied to the specimen through the diamond tip. This makes it possible to construct a high stiffness loading fixture. The magnitude of load applied to the specimen is measured by a strain gauge type load cell with a load resolution of 10 νN. The specimen stage and load cell can be moved to adjust the loading position precisely by a stepping motor at a translation resolution of 0.1 νm. Cantilever beam type specimens with dimensions of 10 × 12 × 50 νm3 were prepared from a Ni-P amorphous thin film by focused ion beam machining. Very small cyclic load (ΔP = 0.1 - 40 mN) was able to be applied to the specimen successfully. This machine appears to be promising for evaluation of fatigue properties for micro-sized specimens for MEMS applications.

Fracture behavior of micro-sized Ni-P Amorphous alloy specimens has been investigated using a newly developed mechanical testing machine. Specimens with dimensions of 10 × 12 × 50 μm were prepared by focused ion beam machining. Two types of specimens with different crack geometries were prepared. One specimen has a notch with root radius is 0.25 μtm and the other has a fatigue pre-crack. The shapes of the loaddisplacement curves are different for each type of specimen. The fracture strength of the specimens with a notch is higher than that with a fatigue pre-crack and the fracture surfaces of the specimens are also different for each type of specimen. This may be due to the difference in stress concentration at the crack (notch) tip, and indicates that even a notch with a root radius of 0.25 μm is not able to be regarded as a crack for micro-sized specimens. Therefore, the introduction of a fatigue pre-crack is essential for the evaluation of fracture toughness for such micro-sized specimens.