-Electronic Structure and Its Energy in Benzene
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-Electronic Structure and Its Energy in Benzene
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and
Akiko Kobayashi
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Articles
Analitical and Inorganic
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Hiroyuki Nariai,
and
Itaru Motooka
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Articles
Orgainc and Biological
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and
Kohtaro Osakada
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and
Masatoshi Motoi*
-Silylene Ligands
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Yuko Aoki, and
Tsutomu Katsuki*
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Ka
mierczak and
Lech Skulski*
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-[2-(2-Troponylthio)ethyl]-
-(2-troponylthio)oligo(oxyethylene)
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and
Hitoshi Takeshita*,
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and
Hitoshi Sumi*,
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Kobayashi,*
Mitsuhiro Moriwaki, and
Iwao Hachiya
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Articles
Applied and Materials
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Copyright (C) 1997 The Chemical Society of Japan
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Accounts
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Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 1-28 (1997) [Vol. 70, No. 1, January, 1997]
The fundamental concepts of catalysis on electron transfer are presented and the mechanistic viability is described by showing a number of examples of both thermal and photochemical reactions that involve catalyzed electron transfer processes as the rate-determining steps.
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Articles
General and Physical
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 29-35 (1997) [Vol. 70, No. 1, January, 1997]
In solution, I with cis phenyl groups exist largely in chair conformation with equatorial orientations of the substituants. However, I with trans phenyl groups and R=H exist as an equilibrium mixture of two non-equivalent chair conformations and boat forms.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 37-45 (1997) [Vol. 70, No. 1, January, 1997]
The kinetics of a successive one-electron oxidation of benzidine to the mono radical cation and dication by several oxidizing agents were investigated by a stopped-flow technique. The experimentally determined rate constants for the oxidative electron-transfer reactions were correlated theoretically using the Marcus theory; the observed and calculated rate constants show good agreement.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 47-53 (1997) [Vol. 70, No. 1, January, 1997]
Neutron diffraction measurements were carried out on 6
Li/7
Li isotopically substituted aqueous 10, 25, and 33 mol% LiBr solutions. Information concerning the short-range structure around Li+
is derived from the least-squares fit analysis for both the difference interference function, 
Li
(Q
), and the distribution function, GLi
(r
).
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 55-59 (1997) [Vol. 70, No. 1, January, 1997]
Triphenylamine neutral and hole (radical cation) molecules are optimized by ab initio Hartree-Fock calculations at the 3-21G basis set. Modest changes in geometry are computed upon oxidation. The unpaired electron is 59% localized on the amine nitrogen atom. The energy barrier for the hopping process involving the electron transfer between a neutral and ionized (hole) triphenylamine is 0.15 eV. The vibrational mode that is primarily associated with the change in geometry upon hole formation is the C-N stretching mode.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 61-70 (1997) [Vol. 70, No. 1, January, 1997]
-Electronic Structure and Its Energy in Benzene
The relationships between the bond order of electrons (Prs
) and the total energy (E
), -electronic energy (E
), and the residue (E
'
) are found as they all show the minimum at the optimum Prs
. This shows that the electrons of benzene has a propensity for uniform distribution.
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 71-78 (1997) [Vol. 70, No. 1, January, 1997]
Photoemissions for ions resulting from the He(23
S) Penning ionization of simple molecules have been studied using a crossed-beam method. The interaction potentials between He(23
S) and the targets are discussed on the basis of the dependences of the emission cross sections (em
) on the collision energy (ER
).
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 79-88 (1997) [Vol. 70, No. 1, January, 1997]
Fourteen isomers of three types of cyclic HNOx (x=2 -6) were found to be at the local minima on the potential energy surfaces with the ab initio MO calculation of the HF/6-31G** and MP2/6-31G** levels of approximation. Some significant features of the optimized geometries, calculated harmonic vibrational frequencies and atomic charges as well as the conformational preferences were discussed.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 89-95 (1997) [Vol. 70, No. 1, January, 1997]
Linearization of the equations of regression makes it possible to resolve the various problems of the conventional non-linear least-squares analyses. Not only the rate constants but also the relative detection sensitivities of different vibrational levels can be determined without information on photochemical parameters.
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Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 97-105 (1997) [Vol. 70, No. 1, January, 1997]
The dynamics of benzene and p -xylene adsorbed in H-ZSM-5, Na-, and H-type mordenites, H-Y, Na-Y, Na-X, and FSM-16 has been studied at room temperature by 13 C and 1 H MAS NMR spectra. There is a good correlation between the pore size and the mobility of the guest species.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 107-114 (1997) [Vol. 70, No. 1, January, 1997]
and
Akiko Kobayashi
The charge-transfer salts of STF were synthesized and characterized. Many of them are isostructural with their corresponding salts of the symmetrical donor(s), but have an orientational disorder at the donor sites. Some of them exhibited similar metallic behavior as that of the two symmetrical donors' salts; others exhibited totally different behavior.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 115-121 (1997) [Vol. 70, No. 1, January, 1997]
Standard enthalpy and entropy changes for the dimerization of 2-[(2-hydroxy-1-naphthyl)azo]-5-[(4-sulfonatophenyl)azo]benzenesulfonate in the presence of 0.05 mol dm-3 salt were found to be highly dependent on the coexisting cation species, with an enthalpy-entropy compensation relation with a compensation temperature of 300 K. This was interpreted by the condensation of cations around the dimer and the difference in the hydration structure of cations.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 123-127 (1997) [Vol. 70, No. 1, January, 1997]
A computer program for 3D substructure searches, SS3D, is described. The program can identify all of the query-corresponding sites within each molecule in the database. It is executable for not only a connected query substructure, but also for a set of disconnected substructures.
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Articles
Analitical and Inorganic
=============================
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 129-133 (1997) [Vol. 70, No. 1, January, 1997]
The Rayleigh light scattering of bromopyrogallol red (solid line) is greatly enhanced by the addition of proteins (dashed line). Based on this fact, a new quantitative method for protein assay has been established. The assay is very sensitive, with a linear range of 0.136-6.80 g ml-1
.
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 135-142 (1997) [Vol. 70, No. 1, January, 1997]
Two hydrates of nitric acid in addition to the anhydrous acid were found in dodecane, as well as in benzene, by the distribution method. One is a molecular monohydrate, and the other is an ionic decahydrate. The decahydrate seems to be an ion-pair of the H+
(H2
O)4
ion and the NO3
-
(H2
O)6
ion.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 143-148 (1997) [Vol. 70, No. 1, January, 1997]
Hiroyuki Nariai,
and
Itaru Motooka
A novel layered cerium(IV) bis(hydrogenphosphate) dihydrate, Ce(HPO4
)2
.2H2
O, which has longer interlayer distance (d=18.0
) than any previously studied layered phosphate, was prepared by the hydrothermal reaction of CeO2
and H3
PO4
in an autoclave. The optimum conditions for the preparation of Ce(HPO4
)2
.2H2
O were established: the mixing ratio (P2
O5
/CeO2
) of H3
PO4
and CeO2
is 1.5-2.0, heating temperature 175-200 °C, heating time 5 h, and water vapor pressure 5.0-7.0 atm. Chemical properties (thermal stability, phase transition, solubility, and adsorption of ammonia) of Ce(HPO4
)2
.2H2
O were studied.
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 149-153 (1997) [Vol. 70, No. 1, January, 1997]
Structural characterization of three types of HMPA-coordinated LnI2 (Ln=Sm , Yb) complexes, [Yb(hmpa)4 (thf)2 ]I2 ( 1 ), [SmI2 (hmpa)4 ] ( 2 ), and [Sm(hmpa)6 ]I2 ( 3 ), which are isolated from reactions of LnI2 with hmpa, has been carried out. The influence of hmpa on the reactivity of SmI2 is discussed, based on the structural data of these complexes.
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Articles
Orgainc and Biological
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 155-167 (1997) [Vol. 70, No. 1, January, 1997]
(1,4-Diazabicyclo[2.2.2]octane)(tetrahydroborato)zinc complex is a stable compound which has been used for the selective reduction of aldehydes, ketones,
,
-unsaturated carbonyl compounds,
-diketones, acyloins and acyl chlorides to their alcohols and aldehydes in THF or CH2
Cl2
/hexane at room temperature or under reflux conditions. The representative reactions are as follows:
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 169-174 (1997) [Vol. 70, No. 1, January, 1997]
and
Kohtaro Osakada
Reactions of molybdenocene and tungstenocene derivatives [M(Cp)2
(H)2
], [M(Cp)2
H(OTs)], or [{M(Cp)2
H(
-Li)}4
] (M=Mo
, W) with [Co2
(CO)8
] or [Co(CO)4
]-
gave [M(Cp)2
H(CO)]+
[Co(CO)4
]-
and [M(Cp)2
(
-H)(
-CO)Co(CO)3
] depending on the reaction conditions employed.
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 175-187 (1997) [Vol. 70, No. 1, January, 1997]
and
Masatoshi Motoi*
A series of polyoxetanes were obtained from oxetanes 1 by their BF3 -initiated ring-opening polymerization, and were found to be thermotropic liquid-crystalline polymers showing nematic and/or smectic mesophases over a wide temperature range from about 250 °C to room temperature. The benzoate moiety and longer tails of the pendant mesogen and the polymer main chain are important segments required for forming the stable smectic mesophase.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 189-195 (1997) [Vol. 70, No. 1, January, 1997]
-Silylene Ligands
Reaction of [RhClL2
] (L=P
(i
-Pr)3
) with tris(2-phenylethyl)silane gives a dinuclear Rh(IV) complex, [RhL(H)2
{
-Si(CH2
CH2
Ph)2
}2
Rh(H)2
L] (
1
), and ethylbenzene. The initial product of the reaction contains mononuclear Rh(III) complexes, [RhCl(H)2
L2
] (
2
) and [RhCl(H){Si(CH2
CH2
Ph)3
}L2
] (
3
).
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 197-206 (1997) [Vol. 70, No. 1, January, 1997]
The treatment of aldehydes or ketones with bis(1,5-cyclooctanediylboryl) selenide ( 1 ) and 2,3-dimethyl-1,3-butadiene afforded the [4+2] cycloadducts of the diene with in situ generated selenoaldehydes or selenoketones, respectively. The one-step conversion of amides, an ester, and sterically hindered ketones to the corresponding selenocarbonyl compounds was also achieved using 1 .
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 207-217 (1997) [Vol. 70, No. 1, January, 1997]
Yuko Aoki, and
Tsutomu Katsuki*
Newly introduced title compounds were found to be efficient chiral auxiliaries for asymmetric Simmons-Smith cyclopropanation of allylic alcohols and for asymmetric addition of diethylzinc to aldehydes. On the basis of NMR and X-ray experiments, a monomeric seven-membered zinc complex of 1 is considered to catalyze the above reactions.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 219-224 (1997) [Vol. 70, No. 1, January, 1997]
Kamierczak and
Lech Skulski*
Oxidative anion metatheses in diaryliodonium halides gave the corresponding hydrogensulfates, nitrates, tetrafluoroborates, triflates, tosylates, as well as bromides and chlorides from only the iodides, via the intermediate dihaloiodates(I). These easy and effective procedures may be extended to other ionic
organic and inorganic halides, with the exception of the fluorides.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 225-230 (1997) [Vol. 70, No. 1, January, 1997]
A few novel branched-chain functionalized sugars, which have important functions, such as hydroxy, hydro, chloro, or azido at quaternary carbon, were stereoselectively prepared in good yield via the same intermediary, 3-C
-,3-O
-chloromethylene- or 3-C
-dichloromethyl-1,2 : 5,6-di-O
-isopropylidene-
-
d
-furanose derivatives.
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 231-237 (1997) [Vol. 70, No. 1, January, 1997]
-[2-(2-Troponylthio)ethyl]-
-(2-troponylthio)oligo(oxyethylene)
and
Hitoshi Takeshita*,
Similar to dithiocrown ethers, a series of podand-type oligoethylene glycols having 2-troponylthio pendants at
- and
-positions formed complexes with Hg(II) salts to be effective mercurophiles; transport through CHCl3
membrane was faster in the higher derivatives.
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 239-244 (1997) [Vol. 70, No. 1, January, 1997]
and
Hitoshi Sumi*,
The viscosity dependence of the rate of the thermal Z /E isomerization of substituted N -benzylideneanilines was studied in a nonpolar solvent. The results clearly indicated a necessity to describe thermal fluctuations of the solvent and the chemical conversion of the reactant by two independent coordinates.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 245-251 (1997) [Vol. 70, No. 1, January, 1997]
The treatment of 4-benzyloxy-1-butyne with PhMe2 SiMgMe in the presence of a catalytic amount of MnCl2 gave a monosilylated product, (E )-PhCH2 OCH2 CH2 CH=CHSiMe2 Ph, selectively after an aqueous workup. Meanwhile, the reaction of isoprene with PhMe2 SiMgMe under a manganese catalysis and subsequent addition of iodomethane afforded 4-dimethylphenylsilyl-2,3-dimethyl-1-butene in good yield.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 253-260 (1997) [Vol. 70, No. 1, January, 1997]
Reduction of dichlorobis(dialkylamino) silanes by alkali metals generated the corresponding bis(dialkylamino)silylenes, which were successfully trapped by various reagents. The intermediacy of amino-bridged dimers of the silylenes was evidenced by scrambling of the amino-substituents during the simultaneous generation of two different bis(dialkylamino)silylenes.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 261-265 (1997) [Vol. 70, No. 1, January, 1997]
Highly efficient energy transfer from tryptophans to biotin-linked pyrenylalanine in avidin tetramer was observed. The energy transfer efficiency reached 85% when two of the four subunits were occupied with biotin-linked pyrenylalanine. The transfer efficiency was simulated, taking the distribution of the biotin derivatives among the four binding sites into account.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 267-273 (1997) [Vol. 70, No. 1, January, 1997]
Kobayashi,*
Mitsuhiro Moriwaki, and
Iwao Hachiya
Group 3 and 4 metal triflates (Sc(OTf)3 , TiCl(OTf)3 , Zr(OTf)4 , and Hf(OTf)4 ) were found to be efficient catalysts in the Fries rearrangement of phenyl or 1-naphthyl acylates. It was also found that the o -acylation (direct acylation) reactions of phenols and 1-naphthols with acid chlorides proceeded smoothly in the presence of the triflates.
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Articles
Applied and Materials
=============================
Copyright (C)
1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 275-281 (1997) [Vol. 70, No. 1, January, 1997]
The radical polymerization of styrene was performed by benzoyl peroxide as an initiator in the presence of HTEMPO. It was found that the polymerization proceeded in the accordance with a living mechanism, giving the polystyrene with the HTEMPO moiety at the polymer chain end.
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1997 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
70, 283-291 (1997) [Vol. 70, No. 1, January, 1997]
A new method for preparing porous supports was investigated by heating a sol-gel-derived SiO2 -ZrO2 microspherical gel in the presence of NaCl. The products in the SiO2 -ZrO2 -Na2 O system comprised a sponge-like structure similar to the porous glasses manufactured by phase separation.
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