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91.
Toshiyuki Yokoi Syusaku Sato Yoichiro Ara Daling Lu Yoshihiro Kubota Takashi Tatsumi 《Adsorption》2010,16(6):577-586
Chiral mesoporous silica (CMS) has been successfully synthesized in the presence of basic amino acids; the use of basic amino
acids in combination with the chiral anionic surfactant is advantageous for the formation of CMS in terms of uniformity in
the twisted morphology. We first demonstrate that thus obtained chiral mesoporous silicas can be used for the enantioselective
separation of racemic compounds; the helical rod-shaped CMS is found to be capable of asymmetric separation of racemic N-trifluoroacetylalanine ethyl ester (CF3CO-Ala-OEt). The left handedness-rich CMS shows asymmetric preferential adsorption of the L isomer and vice versa. 相似文献
92.
93.
Zhou ZB Matsumoto H Tatsumi K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(8):2196-2212
New cyclic quaternary ammonium salts, composed of N-alkyl(alkyl ether)-N-methylpyrrolidinium, -oxazolidinium, -piperidinium, or -morpholinium cations (alkyl = nC4H9, alkyl ether = CH3OCH2, CH3OCH2CH2) and a perfluoroalkyltrifluoroborate anion ([R(F)BF3]-, R(F) = CF3, C2F5, nC3F7, nC4F9), were synthesized and characterized. Most of these salts are liquids at room temperature. The key properties of these salts--phase transitions, thermal stability, density, viscosity, conductivity, and electrochemical windows--were measured and compared to those of their corresponding [BF4]- and [(CF3SO2)2N]- salts. The structural effect on all the above properties was intensively studied in terms of the identity of the cation and anion, variation of the side chain in the cation (i.e., alkyl versus alkyl ether), and change in the length of the perfluoroalkyl group (R(F)) in the [R(F)BF3]- ion. The reduction of Li+ ions and reoxidation of Li metal took place in pure N-butyl-N-methylpyrrolidinium pentafluoroethyltrifluoroborate as the supporting electrolyte. Such comprehensive studies enhance the knowledge necessary to design and optimize ionic liquids for many applications, including electrolytes. Some of these new salts show desirable properties, including low melting points, high thermal stabilities, low viscosities, high conductivities, and wide electrochemical windows, and may thus be potential candidates for use as electrolytes in high-energy storage devices. In addition, many salts are ionic plastic crystals. 相似文献
94.
Shirokura N Nakajima K Nakabayashi A Lu D Hara M Domen K Tatsumi T Kondo JN 《Chemical communications (Cambridge, England)》2006,(20):2188-2190
Ordered mesoporous transition metal oxides were successfully crystallized after strengthening the amorphous framework by a silica layer, which efficiently protected the original mesoporous structure against crystallization and resulting mass transfer. 相似文献
95.
Senda S Ohki Y Hirayama T Toda D Chen JL Matsumoto T Kawaguchi H Tatsumi K 《Inorganic chemistry》2006,45(24):9914-9925
A series of [Tm(Me)M(mu-Cl)]2 and Tm(R)MCl (Tm(R) = tris(mercaptoimidazolyl)borate; R = Me, tBu, Ph, 2,6-iPr2C6H3 (Ar); M = Mn, Fe, Co, Ni) complexes have been prepared by treatment of NaTm(Me) or LiTm(R) with an excess amount of metal(II) chlorides, MCl2. Treatment of Tm(R)MCl (R = tBu, Ph, Ar) with NaI led to a halide exchange to afford Tm(R)MI. The molecular structures of [Tm(Me)M(mu-Cl)]2 (M = Mn, Ni), [Tm(Me)Ni(mu-Br)]2, Tm(tBu)MCl (M = Fe, Co), Tm(Ph)MCl (M = Mn, Fe, Co, Ni), Tm(Ar)MCl (M = Mn, Fe, Co, Ni), Tm(Ph)MI (M = Mn, Co), and Tm(Ar)MI (M = Fe, Co, Ni) have been determined by X-ray crystallography. The Tm(R) ligands occupy the tripodal coordination site of the metal ions, giving a square pyramidal or trigonal bipyramidal coordination geometry for Tm(Me)M(mu-Cl)]2 and a tetrahedral geometry for the Tm(R)MCl complexes, where the S-M-S bite angles are larger than the reported N-M-N angles of the corresponding hydrotris(pyrazolyl)borate (Tp(R)) complexes. Treatment of Tm(Ph)2Fe with excess FeCl2 affords Tm(Ph)FeCl, indicating that Tm(R)2M as well as Tm(R)MCl is formed at the initial stage of the reaction between MCl2 and the Tm(R) anion. 相似文献
96.
A new 2-D coordination network with 22.2-A square-grid coordination networks was prepared from a dicopper(II) tetraacetate [Cu2(AcO)4] as a linear linker motif and 5,10,15,20-tetra-4-pyridyl-21H,23H-porphine (H2TPyP) as a four-connected vertex, forming a regular high-porous structure. The characterization by N2 adsorption indicated that this coordination network has uniform micropores and gas adsorption cavities. 相似文献
97.
A coordinatively unsaturated iron‐methyl complex having an N‐heterocyclic carbene ligand, [Cp*Fe(LMe)Me] ( 1 ; Cp*=η5‐C5Me5, LMe=1,3,4,5‐tetramethyl‐imidazol‐2‐ylidene), is synthesized from the reaction of [Cp*Fe(TMEDA)Cl] (TMEDA=N,N,N′,N′‐tetramethylethylenediamine) with methyllithium and LMe. Complex 1 is found to activate the C? H bonds of furan, thiophene, and benzene, giving rise to aryl complexes, [Cp*Fe(LMe)(aryl)] (aryl=2‐furyl ( 2 ), 2‐thienyl ( 3 ), phenyl ( 4 )). The C? H bond cleavage reactions are applied to the dehydrogenative coupling of furans or thiophenes with pinacolborane (HBpin) in the presence of tert‐butylethylene and a catalytic amount of 1 (10 mol % to HBpin). The borylation of the furan/thiophene or 2‐substituted furans/thiophenes occurs exclusively at the 2‐ or 5‐positions, respectively, whereas that of 3‐substituted furans/thiophenes takes place mainly at the 5‐position and gives a mixture of regioisomers. Treatment of 2 with 2 equiv of HBpin results in the quantitative formation of 2‐boryl‐furan and the borohydride complex [Cp*Fe(LMe)(H2Bpin)] ( 5 ). Heating a solution of 5 in the presence of tert‐butylethylene led to the formation of an alkyl complex [Cp*Fe(LMe)CH2CH2tBu] ( 6 ), which was found to cleave the C? H bond of furan to produce 2 . On the basis of these results, a possible catalytic cycle is proposed. 相似文献
98.
Kamino S Horio Y Komeda S Minoura K Ichikawa H Horigome J Tatsumi A Kaji S Yamaguchi T Usami Y Hirota S Enomoto S Fujita Y 《Chemical communications (Cambridge, England)》2010,46(47):9013-9015
A new class of rhodamine luminophores, 3',3'-bis(oxospiroisobenzofuran)-3,7-bis(dialkylamino)benzopyrano-xanthene derivatives (ABPX), have been successfully developed. The emission behavior of ABPX series is directly opposite to the concentration quenching of conventional rhodamine dyes. ABPX series exhibit aggregation-induced emission enhancement (AIEE). 相似文献
99.
100.
A new formulation is presented to treat fluctuations around the kaon condensate. Equation of state (EOS) is given for isothermal and isentropic cases in the heavy-baryon-limit (HBL). The coexistent phase appears in the latter case. The mass-radius relation is given for protoneutron stars and the possibility of the delayed collapse is discussed. 相似文献