Takanori Suzuki,
Tsutomu Miyashi,
and
Yoshiharu Usui
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Takanori Suzuki,
Tsutomu Miyashi,
and
Yoshiharu Usui
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Kenta Takahashi,
Tatsuma Fukumoto, and
Yoichi Sasaki
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and
Hiroshi Masuhara*
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Chen-Ho Tung
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Analitical and Inorganic
=============================
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-diketonate Complexes
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-alanate
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Junnosuke Fujita,
and
Kiyohiko Nakajima
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Orgainc and Biological
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S. Mani Naidu,
and
M. Krishnaiah
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-Diazocarbonyl Compounds in Nitriles
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Junzo Shoji,
Tetsuro Shingu,
Ryuichi Isobe,
and
Tetsuya Kajimoto
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and
Yoshiyuki Ichinohe
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and
Yukio Nishimura
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ro Ojima,*
and
Gaku Yamamoto*,
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-Dehydroamino Acid Residue by Using Papain
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System in 1,4-Difluorobenzene-Naphthalene Biplanemer
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-Tocopherol:
Scandium(III) Trifluoromethanesulfonate as an Efficient Catalyst in the Reaction of Hydroquinone with Allylic Alcohol
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Kenji Hayashi,
and
Hisashi Yamamoto*
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-Lactones Starting from
,
-Unsaturated Carboxylic Esters
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Yumi Yajima,
Motohiro Akazome,
Makoto Fujita, and
Katsuyuki Ogura*
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and
Syouichi Kobayashi
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-Pyrone Unit
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Articles
Applied and Materials
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and
V. S. Darshane
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Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3289-3307 (1995) [Vol. 68, No. 12, December, 1995]
Chromatographic enantioseparations on a variety of polysaccharides derivatives involving tribenzoates and tris(phenylcarbamates) of cellulose and amylose as chiral stationary phases are reviewed. These CSPs can be used for both analytical and preparative separations of enantiomers, including many drugs. Some significant mechanistic aspects are also briefly reviewed.
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Headline Articles
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3309-3318 (1995) [Vol. 68, No. 12, December, 1995]
The photochemical reaction of ammonia clusters in the first excited state has been studied by a femtosecond pump-probe technique and time-of-flight mass spectroscopy. We also examined the lifetimes of NH4 (NH3 )n with nanosecond lasers. The mechanisms of the formation and decay processes for NH4 (NH3 )n as well as that for RE2PI of ammonia clusters are discussed on the basis of these results.
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=============================
Articles
General and Physical
=============================
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3319-3324 (1995) [Vol. 68, No. 12, December, 1995]
In ethanol(10%)-water mixed solutions, the reaction rate for complex formation between colloidal chitin and chlorophyll a (chl.a) shows an oscillatory dependence on their concentration ratio. At the ratio of 7.4×1,2,4... of sugar units of chitin to one chl.a molecule, a host-guest complex of chl.a with colloidal chitin is produced. Another oscillatory phenomenon is also found as a function of the ethanol concentration.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3325-3329 (1995) [Vol. 68, No. 12, December, 1995]
Oxidation of bicyclic alcohols (borneol and isoborneol) with quinolinium dichromate (QDC) gave camphor. A cyclic transition state is suggested; being a H
ckel-type system (4n+2
), this would be an allowed process.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3331-3335 (1995) [Vol. 68, No. 12, December, 1995]
In a substitutionally and orientationally disordered DBN-BCN mixed crystal mixed with a supertrap impurity, the experimental results show that the triplet exciton transport is percolation-limited in two-dimensional topology.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3337-3339 (1995) [Vol. 68, No. 12, December, 1995]
Takanori Suzuki,
Tsutomu Miyashi,
and
Yoshiharu Usui
The 17 O satellites and the second-generation satellites with extremely low intensity arising from both 13 C and 33 S isotopes in natural abundance were detected from the ESR spectrum of the anion radical of the title quinone. The signs of hfs constants of these nuclei were determined from the analysis of line width effects.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3341-3345 (1995) [Vol. 68, No. 12, December, 1995]
A sum-over-states (SOS) third-order perturbation theory using a semi-empirical wavefunction was applied to 29 Si and 13 C magnetic shielding constants of SiX4 and CH4-n Xn , respectively. The results were in good agreement with the experimental values (Fig. 1), indicating the importance of the spin-orbit effect (LS shift) on the chemical shifts of molecules containing halogen heavier atoms.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3347-3354 (1995) [Vol. 68, No. 12, December, 1995]
Crystal structures have been determined for the title compounds with different phase sequences. Each crystal has a smectic-like layer structure, in which the molecular tilt angle is 25° in 1 and 15° in 2 . Packing modes and the molecular conformations are similar in both crystals, except for the long chains of the chiral groups in 2 , which are twisted and arranged between layers.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3355-3363 (1995) [Vol. 68, No. 12, December, 1995]
1,2-Dichlorotrifluoroethane dissociated via the competitive C-Cl bond rupture and HCl elimination with the branching ratio of 0.66+0.05-0.09
: 0.34+0.09-0.05
after the infrared multiphoton absorption at laser fluence of 16±3
J cm-2
. Secondary photodissociations of the primary products also occurred.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3365-3371 (1995) [Vol. 68, No. 12, December, 1995]
Kenta Takahashi,
Tatsuma Fukumoto, and
Yoichi Sasaki
Pulse radiolysis of a ruthenium(III,III) oxo-acetato dinuclear complex, [Ru2
(
-O)(
-CH3
COO)2
(pyridine)6
](PF6
)2
(abbr. Ru2
(33)), in acetonitrile was studied. In the solutions containing O2
, Ru2
(33) was competitively reduced by CH3
CN.-
and O2
-
to form Ru2
(32) which was reoxidized by .
O2
CH2
CN to regenerate the parent complex of Ru2
(33).
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3373-3381 (1995) [Vol. 68, No. 12, December, 1995]
Densities and related excess molar volumes of title ternary mixtures have been studied in the -10
t/°C80
temperature range, and some empirical relationships have been applied for fitting procedures. Furthermore, the excess mixing property VE
indicates the absence of stable three-components adducts at all the temperatures investigated.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3383-3389 (1995) [Vol. 68, No. 12, December, 1995]
Unusual absorptive electron spin polarization and heavy atom effects were observed in the photoreduction of the titled quinone (Q) by xanthene dyes (Xn2-
), indicating the production of a contact radical pair (CRP) as the intermediate. On the other hand, in the photooxidation of the titled hydroquinone (H2
Q), a pure ST0
radical pair mechanism is operative to create the spin polarization, suggesting the generation of a solvent-separated radical pair (SSRP).
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Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3391-3396 (1995) [Vol. 68, No. 12, December, 1995]
Electric migration in the film is due to the background electrolyte ions permeating through the film. The impedance responses of the electrodes corroborate that the variations in the charge-transport parameters with the electrolyte concentration can be ascribed to the resultant change in interaction between polymer charges.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3397-3402 (1995) [Vol. 68, No. 12, December, 1995]
and
Hiroshi Masuhara*
Micrometer size effects on photoinduced volume expansion of polyacrylamide microgels having triphenylmethyl cyanide groups in water were studied. The photoresponse time becomes faster with decreasing the gel diameter. The cause was discussed based on spectroscopic and kinetic analyses of the volume expansion processes.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3403-3410 (1995) [Vol. 68, No. 12, December, 1995]
Convergent linear energy relationships are observed among log K
values of 1 : 1 hydrogen-bond complexation of OH- and NH-acids with phosphorus compounds in CCl4
. The behaviors are ascribed to two thermodynamic features: the constancy of the 
H
° ratio and the constancy of the apparent S
° value.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3411-3415 (1995) [Vol. 68, No. 12, December, 1995]
and
Chen-Ho Tung
Upon photoexcitation, a supramolecule composed of benzophenone (BP) and norbornadiene (N) bonded by a rigid steroid undergoes an energy-transfer (ET) reaction in acetonitrile. The ET rate constant from excited triplet BP to N is 6.1×104 s-1 and the quantum yield of ET is 0.14.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3417-3421 (1995) [Vol. 68, No. 12, December, 1995]
The low-frequency Raman bands of the four deuterated p -xylene crystals were studied at various temperatures. The isotopic and temperature effects on the frequencies of the Raman bands indicate that the coupling between the intramolecular torsional vibration of CD3 group and the intermolecular rotational vibrations takes place below about -80 °C.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3423-3428 (1995) [Vol. 68, No. 12, December, 1995]
Cellobiose octa(decanoate), a discotic columnar mesogen, was found to form in hexadecane solution various molecular assemblies such as multimolecular micelles and a thermoreversible gel. This gel, observed even in a dilute solution, may be a new type of gel in which minute liquid crystallites work as cross-links.
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=============================
Articles
Analitical and Inorganic
=============================
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3429-3437 (1995) [Vol. 68, No. 12, December, 1995]
The extraction equilibrium with extractants (HA) was determined by an analysis of the data, log D vs. log [A- ]. Also, the extractability was considered based on complex formation in the aqueous and organic phases. Although the thallium(I) chelates (TlA) were well extracted, the acceptability of an additional ligand on the noncharged chelate was not large.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3439-3443 (1995) [Vol. 68, No. 12, December, 1995]
-diketonate Complexes
The electron paramagnetic resonance spectra of some gadolinium(III)-
-diketonate complexes were observed as frozen solutions. The observed EPR spectra are different from each other due to a change of the ligand. These spectra indicate that the ligand fields and/or coordination structures must affect the 4f-electrons. The zero-field splitting parameters were estimated based on specral simulations of the 8S
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3445-3451 (1995) [Vol. 68, No. 12, December, 1995]
-alanate
X-Ray crystallography revealed that K[V(eddda)].2H2
O and [V(
-alada)(H2
O)2
].H2
O adopt a hexacoordinate structure. These complexes yield an oxo-bridged dinuclear complex upon base hydrolysis. The substitution of coordinated water molecules of the latter complex with carbonate ions yields the heptacoordinate species.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3453-3457 (1995) [Vol. 68, No. 12, December, 1995]
Junnosuke Fujita,
and
Kiyohiko Nakajima
The crystal structures of [M(mmtp)2 ]n+ (M=Fe(II) , Co(III), Cr(0). mmtp=1,1,1-tris(dimethylphosphinomethyl)ethane) were compared, especially concerning the M-P bond lengths. The absorption spectra and cyclic voltammograms were also compared between the Fe(II) and Co(III) complexes.
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=============================
Articles
Orgainc and Biological
=============================
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3459-3464 (1995) [Vol. 68, No. 12, December, 1995]
S. Mani Naidu,
and
M. Krishnaiah
Cyclization of 4,4' -dichloro-2,2' -thiodiphenol (1) with phosphoryl chloride in the presence of triethylamine in dry toluene produced 2,6,10-trichlorodibenzo[d ,g ][1,3,6,2] dioxathiaphosphocin 6-oxide (2), which upon a subsequent reaction in situ with various alcohols (3) under the same reaction conditions produced 2,10-dichloro-6-alkoxy-dibenzo[d ,g ][1,3,6,2]dioxathiaphosphocin 6-oxides (4).
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3465-3467 (1995) [Vol. 68, No. 12, December, 1995]
Two known lindenane sesquiterpenoids, chloranthalactone F and chloranthalactone A photodimer were identified to be the same by direct comparison of samples and spectra, and both of their structures were revised to a new structure, 5 .
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3469-3481 (1995) [Vol. 68, No. 12, December, 1995]
-Diazocarbonyl Compounds in Nitriles
The Rh2
(OAc)4
-catalyzed reaction of
-diazocarbonyl compound with nitrile to give oxazole was found to proceed through a stepwise pathway. The presence of a nitrile ylide intermediate was confirmed by trapping with dipolarophiles.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3483-3490 (1995) [Vol. 68, No. 12, December, 1995]
Junzo Shoji,
Tetsuro Shingu,
Ryuichi Isobe,
and
Tetsuya Kajimoto
Three new triterpenoidal saponins called Julibrosides I-III were isolated from Albizziae Cortex, the dried stem bark of Albizzia julibrissin Durazz . Their structures were determined based on spectral and chemical evidence.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3491-3495 (1995) [Vol. 68, No. 12, December, 1995]
and
Yoshiyuki Ichinohe
The reaction of cholest-4-en-3
-ol in benzene-methanol (3 : 2) in the presence of cis
-dichlorobis(triphenylphosphine)platinum(II)-tin(II) chloride dihydrate complex catalyst for 1 h afforded almost quantitatively 3
-methoxycholest-4-ene. On the other hand, cholest-4-en-3
-ol under similar conditions for 4 h gave 3
-methoxycholest-4-ene preferentially.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3497-3505 (1995) [Vol. 68, No. 12, December, 1995]
and
Yukio Nishimura
The ion-molecule reactions of CF3 + with benzene derivatives (PhX: X=H , CH3 , C2 H5 , C2 H3 , and C2 H) have been studied at near-thermal energy using an ion-beam apparatus. The reaction mechanisms are discussed based on product ion distributions and semi-empirical calculations of the reaction pathways.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3507-3517 (1995) [Vol. 68, No. 12, December, 1995]
Rubidium and cesium tellurocarboxylates were prepared by the reaction of O -silyl tellurocarboxylates with the corresponding metal fluorides. The crystal structures of a series of monochalcogenocarboxylic acid cesium salts, determined by X-ray diffraction, indicate a carbon-oxygen double bond.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3519-3538 (1995) [Vol. 68, No. 12, December, 1995]
ro Ojima,*
and
Gaku Yamamoto*,
Methano-bridged bisdehydroannulenones (m , n=1 and 2) were synthesized and their tropic properties were studied by 1 H NMR and UV spectra under neutral and acidic conditions. Their tropicity was found to be lower than the corresponding non-bridged monocyclic counterparts.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3539-3547 (1995) [Vol. 68, No. 12, December, 1995]
1,2,4-Oxadiazaspiro[4.6]undeca-2,6,8,10-tetraenes were derived from the reactions of N -aryl-2,4,6-cycloheptatrien-1-imines with aromatic nitrile oxides. A study of the substituent effect on the reaction rate revealed that the reactions proceeded through nucleophilic reactions of imines to nitrile oxides.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3549-3555 (1995) [Vol. 68, No. 12, December, 1995]
-Dehydroamino Acid Residue by Using Papain
The enzymatic hydrolysis and coupling of N
-protected dehydrodipeptide methyl esters containing an unusual
-dehydroamino acid (AA) residue were first achieved, despite the requisite of the only neutral and large proteinic
L
-
-amino acid (AA) in the case using papain.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3557-3562 (1995) [Vol. 68, No. 12, December, 1995]
System in 1,4-Difluorobenzene-Naphthalene Biplanemer
The title compound 1 showed a charge-transfer absorption band in the long wavelength region of the spectrum. Its oxidation potential was lower than those of related compounds in which one of the double bonds of 1 was hydrogenated. These observations suggest the existence of the destabilization effects of longicyclic conjugation in 1 .
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3563-3567 (1995) [Vol. 68, No. 12, December, 1995]
The calixarene (
1
)-catalyzed reaction of phenol with benzyl bromide in the presence of KOH in CH2
Cl2
was found to yield only the O
-alkylated product. This reaction proceeded according to Michaelis-Menten type kinetics. The calixarene
1
also catalyzed the reactions of phenols with dichloromethane and 1-chloro-4-nitrobenzene.
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Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3569-3571 (1995) [Vol. 68, No. 12, December, 1995]
-Tocopherol:
Scandium(III) Trifluoromethanesulfonate as an Efficient Catalyst in the Reaction of Hydroquinone with Allylic Alcohol
Kenji Hayashi,
and
Hisashi Yamamoto*
Scandium(III) trifluoromethanesulfonate was found to be an efficient catalyst as a Lewis acid for the condensation reaction of trimethylhydroquinone with isophytol to afford
-tocopherol. The condensation reaction proceeded smoothly using only a 0.001 molar amount of the catalyst. The catalyst could be easily recovered from an aqueous layer after the reaction was completed.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3573-3580 (1995) [Vol. 68, No. 12, December, 1995]
The title compounds were prepared in moderate to good yields via the N -formylation of the 3-acetyl-2-(alkylamino)indolizine derivatives with triethyl orthoformate and acetic anhydride in the presence of zinc chloride followed by intramolecular dehydration under strong alkaline conditions.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3581-3589 (1995) [Vol. 68, No. 12, December, 1995]
In an enzymatic synthesis of sialic acid and KDN, we combined the epimerization of GlcNAc to ManNAc catalyzed by calcium hydroxide, an enzyme-catalyzed aldol reaction, and an improved enzyme-catalyzed decarboxylation of pyruvic acid. Sialic acid and KDN were obtained in high yields (60% from ManNAc and 60% from mannose, respectively).
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3591-3598 (1995) [Vol. 68, No. 12, December, 1995]
A racemate of oxirane 1 was separated into two enantiomers by reaction with a chiral carboxylic acid, followed by separation, hydrolysis, and dehydration. This new optical resolution method was applied to the synthesis of SM-9164, a biologically active enantiomer of antifungal agent SM-8668.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3599-3609 (1995) [Vol. 68, No. 12, December, 1995]
-Lactones Starting from
,
-Unsaturated Carboxylic Esters
Yumi Yajima,
Motohiro Akazome,
Makoto Fujita, and
Katsuyuki Ogura*
A 1-Hydroxyalkyl radical (
2
) added regiospecifically at the
-position of a
,
-unsaturated ester (
1a
or
1b
) having methylthio and p
-tolylsulfonyl groups at the
-position gave an adduct (
3
). Spontaneous condensation occurred in
3
to afford
-lactones (
4a
) or
-(ethoxycarbonyl)-substituted
-lactones (
4b
) efficiently.
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3611-3620 (1995) [Vol. 68, No. 12, December, 1995]
In order to obtain clear evidence of a one-ring flip mechanism, stable carbocations, di-1-azulenyl(1- and 2-naphthyl)methyl hexafluorophosphates ( 1 and 2 ), were synthesized by hydride abstraction of the corresponding hydrocarbons. Low-temperature 1 H NMR spectra of 1 showed that the threshold rotation mechanism was a one-ring flip of 1-naphthyl groups.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3621-3627 (1995) [Vol. 68, No. 12, December, 1995]
and
Syouichi Kobayashi
Trehalose drastically modifies the water structure in yeast cells. About 80% of intracellular water is assigned to bound water in the freeze-dried samples. Trehalose plays a role in lowering the average mobility of the residual water, suggesting the possibility of vitrification of cellular medium.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3629-3636 (1995) [Vol. 68, No. 12, December, 1995]
Olefins such as 1-alkenes are nitrated into nitro olefins in good-to-high yields with nitrogen monoxide along with nitro alcohols as by-products, which are dehydrated into nitro olefins by the treatment with alumina. An equimolar amount of nitrogen gas is evolved during the nitration.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3637-3641 (1995) [Vol. 68, No. 12, December, 1995]
A (p -phenylene)bisiodine(III) reagent 5 prepared from iodosylbenzene and trifluoromethanesulfonic acid or the anhydride shows a high reactivity to alkynes and is used as a (p -phenylene)bisiodine(III) transfer agent. The reactions of 5 with alkynes and 1-trimethylsilyl-1-alkynes give trans -alkenyl(p -phenylene)bisiodonium ditriflates 6 and alkynyl(p -phenylene)bisiodonium ditriflates 7 .
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3643-3649 (1995) [Vol. 68, No. 12, December, 1995]
-Pyrone Unit
The absolute configuration of aureothin has been determined by synthesis of aureonone bearing R -configuration which was introduced by Sharpless asymmetric epoxidation.
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=============================
Articles
Applied and Materials
=============================
Copyright (C)
1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3651-3657 (1995) [Vol. 68, No. 12, December, 1995]
and
V. S. Darshane
The various catalysts of the system CuCr2-x Fex O4 were prepared by the precursor method. Results show CuCrFeO4 is the most active and selective catalyst towards cyclohexanol decomposition and dehydrogenation while CuCr2 O4 is the most selective dehydration catalyst. The reaction mechanism of dehydrogenation and dehydration of cyclohexanol is as illustrated.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3659-3663 (1995) [Vol. 68, No. 12, December, 1995]
NAPO-5 and NAPO-11 were synthesized and characterized by XRD, ESR, DRS, IR, and TGA. Chemical analysis and BET surface area were carried out and acidity was determined by TPD. Catalytic activity of NAPO-5 and NAPO-11 was investigated by means of camphene isomerisation which gives tricyclene and 2-bornene. Selective formation of tricyclene is favorable at lower (WHSV)-1 and temperature.
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1995 The Chemical Society of Japan
Bull. Chem. Soc. Jpn.,
68, 3665-3670 (1995) [Vol. 68, No. 12, December, 1995]
We found that in the liquid-phase synthesis of indole from aniline and ethylene glycol, a CdBr2 -3KBr catalyst gave a high yield of indole. In recycling tests, the catalyst CdBr2 -3KBr exhibited stable yields. The rate of indole formation was determined by evaluating the time course of the reaction under high pressure in a newly devised autoclave.
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