Copper-catalyzed benzylic C-H oxygenation under an oxygen atmosphere via N-H imines as an intramolecular directing group

Copper-catalyzed benzylic C-H oxygenation under an oxygen atmosphere was developed starting from carbonitriles and Grignard reagents via N-H imine intermediates. The present process is characterized by the following two-step sequence in a one-pot manner: (1) addition of Grignard reagents to carbonitriles to form N-H imines and (2) benzylic C-H oxygenation (C═O bond formation) triggered by 1,5-hydrogen atom transfer with transient iminyl copper species.     

C-H functionalization polycondensation of chlorothiophenes in the presence of nickel catalyst with stoichiometric or catalytically generated magnesium amide

Polymerization of 2-chloro-3-substituted thiophenes proceeded with a stoichiometric amount of magnesium amide, TMPMgCl·LiCl, or a combination of a Grignard reagent and a catalytic amount of secondary amine in the presence of a nickel catalyst. Although the nickel-catalyzed polymerization with NiCl(2)dppe, which exhibited high catalytic activity in the reaction of bromothiophenes, was less effective, use of a nickel catalyst bearing N-heterocyclic carbene as a ligand was found to induce polymerization with controlled molecular weight and molecular weight distribution.     

Electroless galvanic inks on inorganic WO3/Al boards

A tungsten trioxide (WO(3)) coated aluminium (Al) substrate exhibits a reversible color change without light irradiation or an electric power supply. The sample turns blue upon exposure to an aqueous acid solution, but exposure to oxygen restores the original light yellow color. This color change is due to the galvanic redox reaction between WO(3) and Al.     

Lithium acetylides as alkynylating reagents for the enantioselective alkynylation of ketones catalyzed by lithium binaphtholate

Chiral lithium binaphtholate effectively catalyzed the enantioselective alkynylation of ketones using lithium acetylide as an alkynylating agent. This is the first example of the catalytic enantioselective addition of lithium acetylide to carbonyl compounds without the aid of other metal sources.     

Chemical trend of Ln-M exchange couplings in heterometallic complexes with Ln = Gd, Tb, Dy, Ho, Er and M = Cu, V

The 4f-3d exchange couplings were definitively and precisely determined in the dinuclear complexes (Ln-M) involving double μ-oxo-bridges, by means of combined high-frequency electron paramagnetic resonance and pulsed-field magnetization techniques, revealing a monotonic decrease of ferromagnetic J(Ln-Cu) in the order of the atomic number, (64)Gd to (68)Er.     

Physicochemical properties and plastic crystal structures of phosphonium fluorohydrogenate salts

Fluorohydrogenate salts of quaternary phosphonium cations with alkyl and methoxy groups (tetraethylphosphonium (P(2222)(+)), triethyl-n-pentylphosphonium (P(2225)(+)), triethyl-n-octylphosphonium (P(2228)(+)), and triethylmethoxymethylphosphonium (P(222(101))(+))) have been synthesized by the metatheses of anhydrous hydrogen fluoride and the corresponding phosphonium bromide or chloride precursors. The three salts with asymmetric cations, P(222m)(FH)(2.1)F (m = 5, 8, and 101), are room temperature ionic liquids (ILs) and are characterized by differential scanning calorimetry, density, viscosity, and conductivity measurements. Linear sweep voltammetry using a glassy carbon working electrode shows these phosphonium fluorohydrogenate ILs have wide electrochemical windows (>4.9 V) with the lowest viscosity and highest conductivity in the known phosphonium-based ILs. Thermogravimetry shows their thermal stabilities are also improved compared to previously reported alkylammonium cation-based fluorohydrogenate salts. Differential scanning calorimetry and X-ray diffraction revealed that tetraethylphosphonium fluorohydrogenate salt, P(2222)(FH)(2)F, exhibits two plastic crystal phases. The high temperature phase has a hexagonal lattice, which is the first example of a plastic crystal phase with an inverse nickel arsenide-type structure, and the low-temperature phase has an orthorhombic lattice. The high-temperature plastic crystal phase exhibits a conductivity of 5 mS cm(-1) at 50 °C, which is the highest value for the neat plastic crystals.     

Iridium-catalyzed enantioselective Pauson-Khand-type reaction of 1,6-enynes

Iridium-chiral diphosphine complex catalyzes an enantioselective intramolecular Pauson-Khand-type reaction to give various chiral bicyclic cyclopentenones. The enantioselective reaction proceeds more smoothly and enantioselectively under a lower partial pressure of carbon monoxide. Moreover, aldehyde can be used as a CO source in the enantioselective carbonylative coupling.     

Sliding acceleration of water droplets on a surface coated with fluoroalkylsilane and octadecyltrimethoxysilane

Both fluoroalkylsilane (FAS) and octadecyltrimethoxysilane (ODS) were coated on oxidized silicon wafers using soaking and CVD method. Smooth coatings with Ra values of less than 1 nm were attained. The slope of the sliding acceleration against the inverse of the droplet mass showed an inflection point. That point shifted to the direction of smaller droplets with decreasing FAS ratio to ODS. The water droplets’ length was increased when the sliding velocity was increased. Fluoroalkylsilane addition to ODS increases the interaction between water and the hydrophobic surface. Results showed that the sliding acceleration of a water droplet depends strongly on the surface ratio of these silanes.