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Research has been conducted on the generation of alpha-fluoromalonaldehyde sodium salt. The reaction of this salt with acid chlorides is described.

The reaction of methyl (S)-N-Boc-pyrrolidine-2-carboxylate and perfluoroalkyllithium reagents obtained from perfluoroalkyl iodides and methyllithium-lithium bromide complex was used to produce chiral perfluoroalkyl N-Boc-pyrrolidyl ketones. The method provided the first efficient and asymmetric access to ([alpha]R)-perfluoroalkylated prolinols.

Research has been conducted on trifluoroacetaldehyde ethyl hemiacetal and hydrate. Results demonstrate that the reaction of these compounds with enamines derived from methyl ketones leads to beta-hydroxy-beta-trufluoromethyl ketones.

Layered LiCoO 2 is usually synthesized after a prolonged sintering process at high temperatures (≥800 °C) for 10-20 h. This study developed a "hydroflux process" to obtain highly crystalline and layered LiCoO 2 at a low temperature of 300 °C within 30 min. Molten mixed hydroxide-containing water molecules significantly accelerated the formation of LiCoO 2 , which showed a highly reversible capacity of 120 mAh g -1 without postannealing. The reaction mechanism study showed fast growth of LiCoO 2 crystals, suggesting that the excess molten hydroxides containing water dissolve the cobalt species of HCoO 2 - . Consequently, the accelerated LiCoO 2 formation suppresses the competing reaction of Co 3 O 4 formation, leading to spinel LiCoO 2 formation at low temperatures. Excess water in the starting materials further accelerated the crystal growth of LiCoO 2 , forming large particles (>1 μm). Moreover, the layered LiCoO 2 began to form at 150 °C. This study is the first experimental demonstration that proves the thermodynamic stability of layered LiCoO 2 at low temperatures (150-300 °C) under ambient pressure. This novel process offers significant energy savings in the production process of LiCoO 2 and other ceramics materials.

NIR absorbing squaraine dyes SQ1-SQ7 having 1 H-benzo[ c, d]indol-2-ylidene as a donor moiety were designed for application in DSSCs. Annulation of the benzene ring to an 3 H-indolium-based anchor moiety led to a red-shifted and broadened absorption band on TiO 2 film, which were reflected in the improved short-circuit current density of SQ2 (6.22 mA cm -2 ) compared to the nonbenzene fused derivative SQ1 (4.39 mA cm -2 ). Although the introduction of a butoxy (SQ4: 806 nm) or dialkylamino group (SQ5-SQ7: 815-820 nm) to the 1 H-benzo[ c, d]indol-2-ylidene-based donor moiety resulted in red-shifted absorption maxima in ethanol compared to the nonsubstituted derivative SQ2 (784 nm), the HOMO energy level of SQ4-SQ7 gave rise to an undesirable approximation to the redox potential of I - /I 3 - . Thus, the butoxy (SQ4: 0.56) and dialkylamino (SQ5-SQ7: 0.25-0.30) derivatives had relatively lower conversion efficiencies. Since the 2-ethylhexyl derivative SQ3 exhibited red-shifted absorption (λ max : 796 nm), suitable HOMO and LUMO energy levels, and relatively efficient restriction of charge recombination, this dye achieved the highest conversion efficiency (1.31%), along with a high IPCE response of over 20% over a wide range from 640 to 860 nm and an onset of IPCE at 1000 nm.

A Pd-catalyzed oxidative silylation of simple olefins with hexamethyldisilane to give allylsilanes has been achieved using molecular oxygen as the sole oxidant. The reaction provides a useful protocol to access synthetically useful allylsilanes from easily accessible simple olefins and hexamethyldisilane without using any oxidants other than O2.

Novel bisboron complexes of bidentate ligands consisting of 1,4-benzoquinone and two pyrrole rings were synthesized by using a simple two-step reaction. In solution, the bisboron complexes showed absorption maxima at ∼620 and 800 nm, which were attributed to the allowed S0 → S2 and forbidden S0 → S1 transitions, respectively. The bisboron complexes did not show any fluorescence, probably because of their highly symmetrical structure which forbids the S0 → S1 transition. Bisboron complexes underwent a two-electron reduction to yield the corresponding aromatic dianion, which showed absorption maxima at ∼410 nm.

Pyrazine-based monoboron complexes bearing two fluorine atoms (BF2 complex) or two phenyl groups (BPh2 complex) on the boron atom were synthesized, and the fluorescence properties were investigated. The BPh2 complexes exhibited red-shifted maximum absorption and maximum fluorescence wavelengths and lower molar absorption coefficients than the corresponding BF2 complexes in n-hexane. The fluorescence quantum yields of the BPh2 complexes were higher than or comparable to the corresponding BF2 complexes owing to the relatively low nonradiative rate constants. Although the nonsubstituted and trifluoromethyl-substituted derivatives did not show solvatochromism, the dimethylamino-substituted BF2 and BPh2 complexes exhibited pronounced solvatochromism in the fluorescence spectra. Dual fluorescence was observed for the dimethylamino-substituted BF2 complex in toluene, 1,4-dioxane, and chloroform, corresponding to locally excited (LE) and twisted intramolecular charge-transfer (TICT) states.

Novel fluorescent mono- and bisboron complexes based on pyrimidine bearing β-iminoenolate ligands were synthesized, and their fluorescence properties were investigated. The nonsubstituted and trifluoromethyl-substituted monoboron complexes showed higher fluorescence quantum yield in solid state than in solution. The dimethylamino derivative of the monoboron complex exhibited positive solvatochromism in the fluorescence spectra. The bisboron complex showed significantly higher molar absorption coefficient and red-shifted maximum absorption and maximum fluorescence wavelengths than the corresponding monoboron complex.

Novel fluorescent dyes, thiazole-boron complexes bearing β-ketoiminate ligands, have been synthesized, and their fluorescence properties were investigated. The BF(2) complexes showed a pronounced aggregation-induced emission enhancement effect because of the restriction of C-Ph intramolecular rotation. The BPh(2) complexes showed higher fluorescence quantum yields than the corresponding BF(2) complexes, both in solution and in the solid state.

A novel fluorescence dye based on pyrazine-boron complexes bearing a β-iminoketone ligand has been synthesized by using a simple two-step reaction. Synthesized complexes exhibited fluorescence in solution (F(max): 472-604 nm) and in the solid state (F(max): 496-624 nm). These complexes showed a larger Stokes shift (3690-4900 cm(-1)) than well-known boron dipyrromethene dyes (400-600 cm(-1), in most cases).

[reaction: see text] Chloral or its hydrate undergoes the carbon-carbon bond-formation reaction with various optically active imines in the absence of any additive, followed by hydrolysis, to produce the corresponding beta-trichloromethyl-beta-hydroxy ketones in good yields with high enantioselectivities. In addition, the products with higher ee values were obtained by a simple recrystallization process.