bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymmetric Epoxidation of Simple Olefins by Chiral Bitetralin-Linked “Twin-Coronet” Porphyrin Catalysts
Authors: Naruta Yoshinori , Ishihara Nobuo , Tani Fumito , Maruyama Kazuhiro 
Published: August 2006

Abstract
Catalytic and asymmetric epoxidation of styrenes and related aryl substituted olefins with the iron complexes of chiral bitetralin (Bitet)–linked “twin–coronet” porphyrins was performed with iodosylbenzene as an oxidant. Among two topological isomers of the catalyst, the eclipsed one (5b) showed higher enantioselectivity than the staggered (6b). With 5b, the resulting epoxides, except for the olefins bearing an electron–donating substituent, were obtained in good to excellent enantioselectivity (54—96% ee), especially for the styrenes with electron–withdrawing substituent(s). Being different from other porphyrin–based chiral catalysts, the catalyst 5b is robust enough under the applied oxidation conditions to exhibit chiral epoxidation with the same ee and the same rate as those of the initial period of the reaction even after about 500 turnovers. The Bitet catalyst is superior in the epoxide enantioselectivity than the corresponding chiral binaphthalene (Binap)–linked catalyst (3b). In the reactions with the catalysts 3b and 5b, good correlation in epoxide ees was observed. Increase of the epoxide ee in the reaction with the Bitet catalyst was elucidated by the shape and size of the reaction cavities of the Bitet were tighter than those of the latter. The observed ees of the substituted styrene oxides showed good correlation with Σσ+ values of their substituent(s). In the reaction with the electron–deficient olefins, π–π* interaction between the HOMO of the electron–rich Bitet auxiliary ring and the LUMO of the electron–deficient aryl ring of the substrate are pointed out as the key for the realization of high ees. Some nitrostyrenes, however, gave rather lower ees in spite of rather higher degree of their electron deficiency. This deviation was elucidated by the mismatching of their frontier orbitals.
Photoinduced Alkoxylation of 2-Vinylpyridinium Ion
Authors: Ishida Akito , Uesugi Tatsumi , Takamuku Setsuo 
Published: August 2006

Abstract
Photoirradiation of 2-vinylpyridine in acidic methanol afforded methyl 2-(2-pyridyl)ethyl ether in a high yield. Reactions in acidic ethanol and 2-propanol also provided the corresponding alkoxyl derivatives along with a considerable amount of 2-ethylpyridine. It was suggested that photoinduced intramolecular charge-shift from the pyridinium ion moiety into the vinyl group initiates the regioselective nucleophilic addition of alcohol.
Correlation of Reaction Rates with a Substituent Constant Scale Derived from Calculated Electron Densities for a Computer Control Algorithm
Authors: Cork David G , Hayashi Nobuyoshi 
Published: August 2006

Abstract
A new σ substituent scale based on electron density calculations by the AM1 quantum mechanical model has been established and used to correlate rates of O-methylation of substituted phenols, as part of a chemical artificial intelligence to control a fully automated apparatus for [11C]methyl iodide labeling.
Electroosmotic Transport of Urea and d-Glucose Solutions across Progesterone Plug Membrane
Authors: Srivastava Mahendra Lal , Ram Bali 
Published: August 2006

Abstract
Studies on hydrodynamic and electroosmotic permeation of water, aqueous solutions of d-glucose and urea in the concentration range 10−4 to 10−3 mol dm−3 across progesterone plug membrane have been carried out to characterize the electrical nature of interface. Phenomenological coefficients have been evaluated from the linear and nonlinear equations obtained. Membrane properties viz., pore radius and zeta potentials have been determined using these coefficients. The nonlinear variation of electroosmotic flow in case of aqueous solutions of urea has been explained on the basis of electrical double layer theory and the structural modifications that are likely to occur at membrane–solution interface because of solute–solvent, solvent–solvent, and membrane–permeant interactions.
Solution Properties of Polyvinylpyridine in Acidic Solvent. I. Solution Properties of Poly(2-vinylpyridine) in Aqueous Solution of Sulfuric Acid
Authors: Yoshida Masafumi , Sakamoto Noriyuki , Ikemi Kimiyoshi , Arichi Shizuo 
Published: August 2006

Abstract
Measurements of the light scattering and viscosity of poly(2-vinylpyridine) (P2VP) in an aqueous (aq) solution of H2SO4 at 25 °C were carried out. Although from Stockmayer–Fixman’s theory the characteristic ratio (C∞) was found to be almost constant over the range from 0.1 M to 5.1 M H2SO4, the long-range interaction parameter was found to change through the minimum. The difference among the interaction parameters of P2VP and those of poly(4-vinylpyridine) (P4VP) reported before is discussed. Both the second virial coefficient (A2) and the mean-square radius of gyration (&lt;s2&gt;) of the atactic P2VP sample based on a light-scattering measurement decreased at first with increasing concentration of H2SO4, and then increased through the minimum. The variation of A2 and &lt;s2&gt; from light scattering with the concentration of H2SO4 has the same tendency as that of the intrinsic viscosity ([η]).
Physical Properties of Binary Mixtures of 3-Propylsydnone–Tetrahydrofuran and 1,2-Dimethoxyethane
Authors: Sasaki Yukio , Miyagawa Ken-ichi , Wataru Nobuyuki , Kaido Hideki 
Published: August 2006

Abstract
The physical properties of binary mixtures of 3-propylsydnone (3-PSD)–tetrahydrofuran (THF) and 1,2-dimethoxyethane (DME) at various temperatures were investigated in terms of the dielectric constant (ε), refractive index (nD), density (ρ), and viscosity (η) measurements. The dielectric constants of these binary mixtures gradually decrease with increasing THF and DME mole fractions (XTHF and XDME). The dielectric constant data can be described by a cubic equation of the THF and DME mole fractions. The nD of these binary mixtures decreases linearly with increasing temperature. A linear relationship exists between the density and the temperature at each XTHF and XDME. The η of these binary mixtures rapidly decrease with increasing XTHF and XDME at low temperature. The excess viscosity (ηE) of the mixtures is negative over the entire THF and DME mole fractions, and has a maximum value at 0.4 XTHF and XDME. The negative value of ηE may be taken as the formation of weakly associated compounds. It was found from the 1H and 17O NMR spectra that the interaction in a 3-PSD–THF mixture occurs highly between the hydrogen of the 4-position in the sydnone ring and the oxygen of the THF molecule. From the ηE and NMR spectra it seems that one of the associated compounds due to weak hydrogen bonding in these binary mixtures is formed at the 0.4 THF and DME mole fractions. The interactions in these binary mixtures were investigated on the basis of the activation parameters by using the Eyring rate equation. The activation enthalpy (ΔHη*) gradually increases with increasing viscosity of the mixtures. It is considered that the mechanism of viscous flow for these binary mixtures is a thermally activated single process. The activation entropy (ΔSη*) gradually changes from positive to negative with increasing XTHF and XDME. It seems that the change of sign in ΔSη* near to 0.4 THF and DME mole fractions depends on the formation of weakly associated compounds at that mole fraction. The activation Gibbs energy (ΔGη*) with a positive ΔSη* value gradually decreases with increasing temperature. On the contrary, the ΔGη* with a negative ΔSη* value gradually increases with increasing temperature. This means that the change in ΔSη* greatly contributes to that of ΔGη*.
Binding of Dibucaine to Phospholipid Mixed Vesicles
Authors: Fukushima Kohsuke , Someya Masayuki , Shimozawa Ryosuke 
Published: August 2006

Abstract
Binding isotherms of a local anesthetic, dibucaine, to phospholipid vesicles were measured using a dialysis method. Two types of phospholipids, dilauroylphosphatidic acid (DLPA) and dilauroylphosphatidylcholine (DLPC), were used to prepare vesicles. The binding isotherms for pure DLPA and DLPC vesicles and their mixtures were analyzed with the Hill equation. The binding parameters obtained for pure phospholipid vesicles reproduce the binding isotherms for the mixed vesicles by taking account of the mixing ratio; this indicates the presence of independent binding sites, corresponding to the DLPA and DLPC molecule, in the mixed vesicle.
The Micellar Properties of α,ω-Alkanediammonium Bis(dodecyl sulfate) in Aqueous Solutions
Authors: Satake Iwao , Fukunaga Tomoko , Maeda Tamaki , Soeda Yuko , Hayakawa Katumitu 
Published: August 2006

Abstract
The micellar properties of α,ω-alkanediammonium bis(dodecyl sulfate) with hydrocarbon chain length (n) from 3 to 6 were studied by conductivity, surfactant ion activity, and fluorescence quenching measurements. The critical micelle concentration (CMC) decreases gradually with increasing n in such a way that ln CMC vs. n plot gives a straight line above n = 3. The binding degree of counterion head group to the micelle remains virtually constant of 0.95 regardless of n studied. The estimated value of −0.36 kT for the transfer free energy per methylene group of counterion from aqueous to micellar environments suggests that the hydrocarbon part of the counterion participates in the weak hydrophobic interaction with micellar core. Although the micelle aggregation number is always larger than those of bivalent metal dodecyl sulfates, it tends to decrease as n increases.
Multi-Reference CI Calculation of Potential Energy Curves for cis–trans Isomerization of Stilbene Cation Radical
Authors: Oshiyama Tomohiro , Takahashi Ohgi , Morihashi Kenji , Kikuchi Osamu , Tokumaru Katsumi 
Published: August 2006

Abstract
Ab initio and AM1 multi-reference SCI calculations have been applied to the stilbene cation radical and the potential energy curves for the lower doublet states were obtained as a function of the twist angle about the central C–C bond to elucidate the photochemical cis–trans isomerization process. The shape of the calculated potential energy curves has suggested that the cis→trans one-way isomerization proceeds very efficiently from an upper excited state of the cis-stilbene cation radical.
CIDEP Study of Radicals Produced Photochemically in the Organic Solution of 9-Acridone and Phenols
Authors: Niizuma Shigeya , Kawata Hiroki 
Published: August 2006

Abstract
The photoreaction of the solution systems of 9-acridone (or N-methyl-9-acridone) and phenols was investigated by optical spectroscopy, ESR, and time-resolved CIDEP techniques. CIDEP signals of acridone semiquinone and phenoxyl radicals were detected together and the hyperfine coupling constants of acridone semiquinone were determined for the first time by simulation method. It was also clarified that radical pair mechanism (RPM) with triplet precursor and triplet mechanism (TM) were the main spin polarization mechanisms in these systems. The results indicate that the excited triplet state of acridone abstracts a hydrogen of phenols. Temperature, phenol concentration, light intensity and time dependence of the phenoxyl CIDEP signal intensity and/or pattern supported the conclusion.
Behavior of Surfactants in the Suspension of Coal Components
Authors: Ogura Tsugitoshi , Tanoura Masazumi , Hiraki Akio 
Published: August 2006

Abstract
The roles and behaviors of an anionic surfactant, such as naphthalenesulfonate-formaldehyde condensate (NSF) and poly(styrenesulfonate) (PSS) in the high-loaded suspensions of the Celejon coal with low mineral content (1.2%), carbon black, kaolinite, and montmorillonite were studied. It was found that it is necessary to prepare a slurry of low-viscosity Celejon coal, carbon black and kaolinite in such a way that the surfactant is present as saturatedly adsorbed on the particles as well as being free in water. In the presence of a surfactant, high-loaded suspensions exhibited non-Newtonian fluidity without yield values in their shear-rate and shear stress relation. In contrast, neither NSF nor PSS showed any adsorption on the bentonite particles. Its suspension exhibited a non-Newtonian fluidity with the yield value, even if its concentration was low. The roles of the bentonite were confirmed by adding bentonite to the CWM of Celejon. The CWM of Taiheiyo coal which carried 4.81% montmorillonite suffered a limited coal concentration due to because of a large yield value. Sodium polycarbonate was found to be effective to reduce the yield value, allowing a high coal concentration in CWM.
O2 and CO Binding Behavior of Double-Sided Porphyrinatoiron(II) Complexes Modified by Amide Residues
Authors: Komatsu Teruyuki , Kumamoto Shin-ichi , Nishide Hiroyuki , Tsuchida Eishun 
Published: August 2006

Abstract
New double-sided porphyrinatoiron(II) complexes having a polar cavity which includes an amide moiety (5,10,15-tris[2,6-bis(3,3-dimethylbutyryloxy)phenyl]-20-[2-[N-acetylvalyloxy]-6-(3,3-dimethylbutyryloxy)phenyl]porphinatoiron(II) (1b) and 5,10,15-tris[2,6-bis(3,3-dimethylbutyryloxy)phenyl]-20-[2-[3,5-bis(acetamido)benzoyloxy]-6-(3,3-dimethylbutyryloxy)phenyl]porphinatoiron(II) (2b)) were synthesized. 1H NMR spectroscopy indicated that the amide residues are located on the porphyrin ring plane. The O2 and CO binding affinities of 1b and 2b were higher than those of 5,10,15,20-tetrakis[2,6-bis(3,3-dimethylbutyryloxy)phenyl]porphinatoiron(II) (4b), in response to the local polarity in the cavity. The polar amide residue resulted in a decreased O2 dissociation rate. Thermodynamic parameters for the gaseous ligand bindings to the 2b complex were also determined.
Cobalt(III) Complexes with Quadridentate Ligands. XII. Crystal Structure of cis-α-Salicylato(triethylenetetramine)cobalt(III) Chloride Pentahydrate
Authors: Sekizaki Haruo , Toyota Eiko , Yamamoto Yoshihisa 
Published: August 2006

Abstract
The structure of the cis-α-salicylato(triethylenetetramine)cobalt(III) ion was confirmed by an X-ray crystallographic analysis. The conformation of the triethylenetetramine part of this complex was slightly different from the cis-α-glycinato(triethylenetetramine)cobalt(III) ion. A comparison of the stability of the this cis-α-salicylato complex with that of the cis-α-glycinato complex on the cation-exchange resin and in water, respectively, are described. The signals of the 1H NMR and 13C NMR spectra were assigned based on the crystal structure.
Preparation and Characterization of Ethylenediaminetrihalogenonitrosylruthenium(III) Complexes
Authors: Tomizawa Hiroshi , Harada Kazumasa , Miki Eiichi , Mizumachi Kunihiko , Ishimori Tatsujiro , Urushiyama Akio , Nakahara Masayoshi 
Published: August 2006

Abstract
A mixture of mer- and fac-[RuCl3(en)NO], and mer-[RuX3(en)NO] (X = Br or I) were prepared from the corresponding [RuX5NO]2− (X = Cl, Br, or I) or hydrous RuX3·NO (X = Cl or Br) and en·2HX (en = ethylenediamine; X = Cl or Br). The crystal and molecular structures of mer-[RuX3(en)NO] (X = Cl, Br, or I) were determined by X-ray diffraction. The crystals were isomorphous; triclinic, with space group P1. The final R values were 0.0411 for [RuCl3(en)NO], 0.0271 for [RuBr3(en)NO], and 0.0535 for [RuI3(en)NO]. In these complexes, the three halogeno atoms were in the meridional arrangement and in a position cis to the NO. In all of the mer-complexes, the trans-strengthening effect which is expected to be caused by the NO was not observed for the Ru–N(en) bond. The synthesized complexes were also characterized by IR and NMR spectra.
Dual Cation-Selective Membrane Tube Electrodialysis/Ion Chromatography for Halide Ions in Strongly Basic Solutions and Its Application to the Analysis of Rock Samples
Authors: Okamoto Yasuaki , Hayashi Kiyoshi , Kawahara Yukihiro , Kumamaru Takahiro 
Published: August 2006

Abstract
Electrodialysis pretreatment system was combined with a new dual cation-selective membrane tubes and was employed to reduce the basicity of the strongly basic sample solution prior to the ion chromatographic determination of halide ions by using a sodium salicylate solution as eluent. By using this system, large amount of cations such as sodium and potassium ions could also be removed from the sample solution through the membrane. The detection limits were 9.7, 5.4, 22.7, and 163 ng cm−3 and relative standard deviations at 0.5 μg cm−3 were 1.7, 1.2, 2.4, and 14% for fluoride, chloride, bromide, and iodide ions, respectively. Analytical results are given for rock samples fused with sodium hydroxide as a flux and afterward dissolved in water which shows strong basicity.
Studies on the Vilsmeier-Haack Reaction. Part XI. Novel Heterocyclo-Substituted Thioquinoxalinone Dyes
Authors: Awad Ibrahim M A 
Published: August 2006

Abstract
Novel azo sulfa drugs of 3-methyl-1-[4-(substituted sulfamoyl)phenylazo]-2(1H)-quinoxalinethiones were synthesized and found to undergo diformylation reaction with Vilsmeier reagent giving the 3-(3-aminoacrylaldehyde-substituted)-1-(4-sulfamoylphenylazo)-2(1H)-quinoxalinethione dyes 4—6. Reaction of 4, 5, and/or 6 with proper reagents afforded the corresponding morpholinyl, piperidinyl, 4-piperazinyl-1H-pyrazol-4-yl, 1-phenyl-1H-pyrazol-4-yl, 4-isoxazolyl, and 5-amino-1H-pyrazol-4-yl substituted 2(1H)-quinoxalinethione derivatives at the 3-position of the quinoxaline moiety. The structures of these novel compounds were confirmed by elemental analysis, IR and 1H NMR spectroscopy and screened in vitro for antibacterial (Gram-positive and Gram-negative bacteria) and antifungal activites.
Preparation and Characterization of 11-Molybdoarsenite(III) Complex
Authors: Maeda Kohji , Himeno Sadayuki , Saito Atsuyoshi , Hori Toshitaka 
Published: August 2006

Abstract
A green 11-molybdoarsenite(III) complex, which was formed in an Mo(VI)–AsO33−–HCl–CH3CN system at room temperature, was isolated as the tetrabutylammonium (n-Bu4N+) salt, being characterized by its voltammetric behavior and its IR and UV-visible spectra. The heteropolyanion undergoes two-step one-electron reductions in CH3CN and three-step two-electron reductions in acidified CH3CN. The electrochemical reduction produces mixed-valence blue species at the glassy carbon (GC) electrode. The formation conditions and chemical properties were compared with those of 12-molybdoarsenate(V) with the Keggin structure. The presence of water-miscible organic solvents like CH3CN and CH3COCH3 is absolutely necessary for the formation of the green heteropolyanion.
Reaction of Hydrazinobenzoquinolines with 1,3-Diketones: A Structural Reinvestigation
Authors: Singh Shiv Pratap , Kapoor Jitander Kumar , Kumar Devinder 
Published: August 2006

Abstract
Reaction of several hydrazinobenzoquinolines with 1,3-diketones affords pyrazolylbenzoquinolines rather than the reported benzodiazepinoquinolines. The structural assignment is based upon NMR (1H and 13C) spectral data and an unambiguous synthesis.
Soluble Itaconic Acid–Ethylene Glycol Polyesters
Authors: Retuert J , Pedram M Yazdani- , Martínez F , Jeria M 
Published: August 2006

Abstract
A method of obtaining soluble itaconic acid (IA)–ethylene glycol (EG) unsaturated polyesters was developed. The reaction between IA and EG was conducted under moderate vacuum (50—60 mmHg) at 120 °C and stopped by nearly 85% conversion to avoid crosslinking. No isomerization of itaconate to citraconate and/or mesaconate was observed. The residual double bond contained in the polyester resin showed to be highly reactive and promoted gelification after few days. Therefore copolymerization reactions of the resin with a variety of vinyl monomers proceed without radical initiator. The synthetic method was successfully applied to reactions of IA with other glycols.
Synthesis of 2,3-Dideoxy-2-[(3R)-3-hydroxytetradecanoylamino]-3-C-[(3R)-(3-hydroxytetradecanoyloxy)methyl]-4-O-phosphono-d-mannopyranose
Authors: Shiozaki Masao , Arai Masami , Hiraoka Tetsuo , Nishijima Masahiro , Akamatsu Yuzuru 
Published: August 2006

Abstract
2,3-Dideoxy-2-[(3R)-3-hydroxytetradecanoylamino]-3-C-[(3R)-(3-hydroxytetradecanoyloxy)methyl]-4-O-phosphono-d-mannopyranose was synthesized from (1R,2S,4S,5S)-6-(2,4-dimethoxybenzyl)-4-hydroxy-2-[(1R)-1,2-isopropyridenedioxyethyl]-3-oxa-6-azabicyclo[3.2.0]heptan-7-one.
Formation and Reactions of Novel Heterocycles: 1,3,4-Oxadithiolane, 1,3,4-Oxadiselenolane, 1,3-Oxathietane, and 1,3-Oxaselenetane Derivatives
Authors: Ding Meng-Xin , Ishii Akihiko , Nakayawa Juzo , Hoshino Masamatsu 
Published: August 2006

Abstract
The reactions of 2,2,4,4-tetramethyl-1,5-diphenyl-1,5-pentanedione monohydrazone with S2Cl2 and Se2Cl2 gave 2,2,4,4-tetramethyl-1,5-diphenyl-8-oxa-6,7-dithiabicyclo[3.2.1]octane (9) and 2,2,4,4-tetramethyl-1,5-diphenyl-8-oxa-6,7-diselenabicyclo[3.2.1]octane (10), respectively. Dechalcogenation of 9 or 10 with triphenylphosphine in boiling toluene yielded an equilibrium mixture of 2,2,4,4-tetramethyl-1,5-diphenyl-6-oxa-7-thiabicyclo[3.1.1]heptane (11) and 2,2,4,4-tetramethyl-1,5-diphenyl-5-thioxo-1-pentanone (13) or 2,2,4,4-tetramethyl-1,5-diphenyl-6-oxa-7-selenabicyclo[3.1.1]heptane (12), respectively. On the other hand, the reaction of 10 with hexamethylphosphorous triamide [P(NMe2)3] in boiling toluene gave 12, 3-methyl-3-(2,2-dimethyl-3-oxo-3-phenylpropyl)-2-phenylselenetanes (18), 5-benzoyl-3,3,5-trimethy1-2-phenylselenanes (19), 6,6,8,8-tetramethyl-9-phenyl-6,7,8,9-tetrahydro-5H-benzocyclohepten-5-one (20), and 3,3,5,5-tetramethyl-1,2-diphenylcyclopentene (21), while that of 9 afforded 11, 13, 3-(2-benzoyl-2-methylpropyl)-3-methyl-2-phenylthietanes, 20, and 21. The reaction of 12 with P(NMe2)3 also gave 18, 19, 20, and 21. A single-electron transfer mechanism seems to be operative in the reaction of 9 or 10 with P(NMe2)3. Compounds 11 and 13 are in equilibrium with each other at room temperature, while a ring-opening of 12 to 2,2,4,4-tetramethyl-1,5-diphenyl-5-selenoxo-1-pentanone is observed on heating by the UV-vis and 1H NMR spectra.
Heterocyclic Synthesis with Nitriles: Synthesis of Some New Mercapto-Substituted Heterocycles from Alkylidenemalononitrile
Authors: Abdelrazek Fathy Mohamed , Salah Abdellatif Mohamed 
Published: August 2006

Abstract
α-(Thiocyanatomethyl)benzylidenemalononitrile undergoes azo coupling with diazotized aromatic amines (ArNH2) to afford azo derivatives. The azo derivatives (Ar = Ph, 4-MeC6H4, 4-ClC6H4, 4-MeOC6H4) were readily cyclized on reflux in aqueous NaOH to 3(2H)-pyridazinimine derivatives. These latter compounds were transformed into the corresponding pyrrole derivatives on reflux in glacial acetic acid with Zn dust presumably via reductive cleavage of the N–N bond followed by recyclization with loss of ammonia. Under similar conditions the azo derivative (Ar = 2-NCC6H4) was cyclized into 6H-pyridazino[3,2-a]quinazolin-6-imine derivative which was easily transformed into the 6H-pyridazino[3,2-a]quinazolin-6-one on reflux in ethanolic HCl. This last compound was also obtained from the azo derivatives (Ar = 2-HOOCC6H4 and 2-MeOOCC6H4) by reflux in aq NaOH. The starting benzylidenemalononitrile reacts also with arylmethyleneamalononitrile or ethyl arylmethylenecyanoacetate (aryl = Ph, furyl, or thienyl) to afford substituted benzonitrile derivatives.
Number and Structure of Solvolysis Intermediates. Part 2. A Novel Example of the Common Ion Rate Depression Arising at the Stage of the Second Ion Pair Intermediate in the SN1 Solvolysis
Authors: Kinoshita Tomomi , Shibayama Koichi , Itoh Masaaki , Takeuchi Ken’ichi 
Published: August 2006

Abstract
The solvolysis of 2,2-dimethyl-1-(p-methoxyphenyl)propyl p-nitrobenzoate in phenol provides a novel example of the common ion salt effect (rate depression) which arises at the stage of the second ion pair intermediate (Int-2; the rear-side shielded ion pair intermediate), not the dissociated (free) carbocation intermediate as generally supposed so far. This example demonstrates that “the common ion rate depression” could not give evidence for the intermediacy of the dissociated carbocation intermediate in the SN1 solvolysis, but an indicator for the stability of solvolysis intermediates including the ion pair intermediate.