bluuebunny/crossref_metadata_2025 huggingface dataset:
The Penetration of Disodium Hexadecyl Phosphate to the Monolayers of Cholesterol and its Esters from the Underlyning Aqueous Solutions
Authors: Nakagaki Masayuki , Handa Tetsurou
Published: July 2006

The surface pressure of the monolayers of cholesterol (CH), cholesteryl acetate(CA), and cholesteryl propionate (CP) on the aqueous solutions of disodium hexadecyl phosphate (SHP) was measured. The monolayer exhibited a more expanded state on the solution than on pure water. The curves showing the surface pressure against the area per molecule of each monolayer had a kink point, which was considered to indicate the collapse of the monolayer. The amount of SHP penetrating into the insoluble monolayer was calculated by means of the Gibbs adsorption equation. It was found that the relation between the penetration amount and the activity of SHP in the aqueous solution could be expressed by a modification of the Langmuir adsorption equation. It was also found that the saturated amount of the penetration decreased, and the Langmuir coefficient increased, with the compression of the monolayer.
Deactivation of Triplet 2-Naphthol and 1-Anthrol by Aromatic N-Heteroeycles
Authors: Yamamoto Sada-aki , Kikuchi Koichi , Kokubun Hiroshi
Published: July 2006

A flash-photolytic investigation was carried out on the hydrogen bonding interaction of triplet 2-naphthol and 1-anthrol with aromatic N-heterocycles such as 4-methylpyridine, quinoline, and benzo[h]quinoline. The deactivation of triplet 2-naphthol and 1-anthrol by aromatic N-heterocycles was found to be due to the hydrogen atom transfer reaction. The relationship between the reactivity and the reduction potential of aromatic N-heterocycles suggests that the electron transfer from the triplet to the quencher is the primary process of the hydrogen atom transfer reaction.
The Effect of Pressure on the Dissociation of Weak Acids in Aqueous Buffers
Authors: Tsuda Motoyuki , Shirotani Ichimin , Minomura Shigeru , Terayama Yoshio
Published: July 2006

The effect of pressure on the dissociation of boric acid, imidazole HCl, and H2PO4− in aqueous buffers has been investigated up to 6 kbars, using as optical indicators p-nitrophenol and Cresol Red. The limiting volume change on ionization at atmospheric pressure (Δ\barV°) and the compressibility change (Δ\barκ°) for these weak acids were obtained. The values of Δ\barV° (cm3 mol−1) and Δ\barκ° (cm3 mol−1 kbar−1) are −10.1 and −0.4 for Cresol Red, −30.2 and −4.3 for boric acid, and −2.4 and −0.6 for imidazole H+.
Selective Hydrogen Atom Abstraction by Hydrogen Atoms in Photolysis and Radiolysis of Alkane Mixtures at 77 K
Authors: Miyazaki Tetsuo , Kinugawa Kazuhisa , Eguchi Masao , Guedes Selma M L
Published: July 2006

A selective hydrogen atom abstraction reaction by H atoms, which are produced at 77K by radiolysis of alkane or photolysis of hydrogen halides, has been found in isobutane, 2,2,3,3-tetramethylbutane (TMB), and cyclopropane matrices as well as in the neopentane matrix. The selective hydrogen atom abstraction reaction is caused by H atoms which have initial kinetic energies in the range from 15 to 67 kcal/mol. The reaction is caused also by D atoms. The competitive reaction between c-C6H12 and HI for H atoms has been studied in the radiolysis and photolysis of neo-C5H12–c-C6H12–HI mixture at 77K. The rate constants of these reactions in the neopentane matrix are quite different from those of a thermal H atom reaction, but similar to those of a hot H atom reaction. The importance of the selective hydrogen atom abstraction reaction by H atoms is pointed out in the radical formation in the radiolysis of pure TMB at 77K.
A Consideration on the Energy Efficiency of Agitation in Emulsion
Authors: Hidaka Hisao , Noro Shun’ichi , Takamura Akira , Koishi Masumi
Published: July 2006

The effects of mechanical factors on the energy efficieucy of agitation in o/w-type emulsions were investigated. The impeller diameters used were 49.0, 65.0, 80.1, and 89.9 mmφ and the number of revolution was set at 200, 330, 400, 530, 660, or 812 rpm. The viscosity ratios (μd⁄μc) were 0.836: 1,0.0861: 1,0.000777: 1, and 0.000173: 1. The size of the dispersed liquid droplets was measured by the microphotographic method. The mean diameter of the droplets, their size distribution, and the agitation torque were determined, and the energy efficiency of agitation was evaluated. When the viscosity ratio was near 0.00861: 1, the energy efficiency of agitation showed a maximum. Furthermore, the energy efficiency decreased as the mean surface-volume diameter became smaller.
The Primary Process of the Photochemical Formation of 1-Nitrenopyrene
Authors: Sumitani Minoru , Nagakura Saburo , Yoshihara Keitaro
Published: July 2006

The primary process of the photo-decomposition of 1-azidopyrene (Py–N3) was studied with the aid of nanosecond time-resolved laser photolysis. An excited singlet 1-nitrenopyrene (Py–N) was identified as an intermediate for the formation of the ground triplet nitrene. The direct photo-decomposition of 1-azidopyrene occurs through Py–N3* (singlet)→Py–N* (singlet)→Py–N (triplet). The lifetime of the excited singlet nitrene was found to be 22 ns at room temperature in benzene and was found to be slightly longer at 77 K.
Vibration Spectra and Rotational Isomerism of Chain Molecules. I. Methyl Propyl Ether, Ethyl Propyl Ether, and Butyl Methyl Ether
Authors: Shimanouchi Takehiko , Ogawa Yoshiki , Ohta Masahiro , Matsuura Hiroatsu , Harada Issei
Published: July 2006

The Raman and infrared spectra of methyl propyl ether, ethyl propyl ether, and butyl methyl ether were measured for the gaseous, liquid, glassy and crystalline states. The normal vibration frequencies were calculated, a consistent set of force constants explaining the frequencies of basic aliphatic ethers being assumed. The rotational isomerism was studied and the following conclusions were obtained. (1) Only the all-trans form exists in the crystalline state. (2) Another form which takes the gauche conformation about the OC–CC axis and the trans conformation about the CC–CC and CO–CC axes exists in the glassy state. (3) Other forms also exist in the liquid state. These results confirmed that the repulsive force between nonbonded hydrogen atoms was one of the important factors influencing the stability of molecular conformations. The stable conformations of the ether molecules were correlated with those of polyether chains.
The Crystal and Molecular Structure of Chloro-α,β,γ,δ-tetraphenylporphinatocobalt(III)
Authors: Sakurai Tosio , Yamamoto Kiyoko , Naito Hirobumi , Nakamoto Nobuaki
Published: July 2006

The structure of the title compound, C44H28N4CoCl, has been determined by single-crystal X-ray diffraction. The crystals are body-centered tetragonal, with a=b=13.693(2), c=9.701(2) Å, and Z=2. The space group was determined to be I4 from the measurement of the anomalous dispersion effect. The structure was predicted prior to the X-ray analysis from the calculation of the intermolecular van der Waals energy; the result agreed quite well with the experimentally determined structure. A tetragonal pyramidal five coordination with the chlorine atom at the apex was found for the cobalt atom. The cobalt-chlorine distance is 2.149 (6) Å, about 0.1 Å shorter than those found in ordinary octahedral coordinations.
Dehydroannulenes. IV. Synthesis and Properties of 1,14-Di-tert-butyl-5,10-diphenyl-6,8,15,17-tetrakisdehydro[18]annulene. Evidence for the Identity of Diacetylene and Hexapentaene Units in the 18π-Electron System
Authors: Nomoto Tateo , Fukui Kunisuke , Nakagawa Masazumi
Published: July 2006

The synthesis designed to lead to isomeric di-tert-butyldiphenyl-tetrakisdehydro[18]annulenes (VII and XIII) have been performed. It was found that the isomeric tetrakisdehydro[18]annulenes (VII and XIII) are identical in all respects, thus providing chemical evidence for the identity of diacetylene and hexapentaene units incorporated in the aromatic 18π-electron system. Argon laster Raman spectra of VII and XIII exhibited single absorption due to stretching vibration of sp-hybridized carbon-carbon bond at 2080 cm−1 indicating equalized nature of acetylenic and cumulenic linkages in the aromatic dehydroannulene system.
Preparation and Ligand Isotopic Exchange of Tris(acetylacetonato)tin(IV) Perchlorate in Acetonitrile
Authors: Nagasawa Akira , Saito Kazuo
Published: July 2006

Tris(acetylacetonato)tin(IV) perchlorate [Sn(acac)3]ClO4 was prepared in crystalline state in acetylacetone (Hacac) and its structure was verified. It is stable in dehydrated acetonitrile (AN) at room temperature. It undergoes hydrolysis in the presence of a large amount of water (e.g., 10−4 mol dm−3 complex against 10−1 mol dm−3 water) in two steps: The first, fast step gives a product [Sn(acac)2(OH)(H2O)]ClO4, which slowly undergoes further hydrolysis or polymerization to give eventually a gelatinous precipitate. The ligand isotopic exchange with Hacac[14C] can be measured in \simeq10−2 mol dm−3 complex solution in AN containing 0.03–0.12 mol dm−3 water below −20 °C. The rate is independent of free Hacac concentration. The dependence of the rates of the hydrolysis and the ligand isotopic exchange on water concentration is expressed by: rate=A[complex][H2O]2/(1+B[H2O]), where the A values are 0.15 and 0.30 dm6 mol−2 s−1 at −20 °C, ΔH\eweq and ΔS\eweq being (50±8) and (36±20) kJ mol−1, and (−60±20) and (111±40) J mol−1K−1, respectively. There seems to be a common rate-determining step in which one acac− ligand dissociates with the action of water. The intermediate gives rapidly the original complex in the presence of excess Hacac. Otherwise it undergoes further hydrolysis in the presence of an over-whelming amount of water. The large ionic radius of tin(IV) should be responsible for the rapid water substitution as compared with the corresponding octahedral silicon(IV) and germanium(IV).
Preparation and Properties of 7-Formyl-8-hydroxy-5-quinolinesulfonic Acid
Authors: Matsumura Konomu , Sasaki Shin-ichi , Tada Eiko
Published: July 2006

8-Hydroxy-5-quinolinesulfonic acid (I), on condensation with formaldehyde in aqueous ammonia, produced 8-hydroxy-7-hydroxymethyl-5-quinolinesulfonic acid (IV), which, on oxidation with manganese (IV) oxide, gave 7-formyl-8-hydroxy-5-quinolinesulfonic acid (V). On treatment with boiling 6 M hydrochloric acid, V produced bis[α-hydroxy-(8-hydroxy-5-sulfo-7-quinolyl)methyl] ether (VIII).
The Finkelstein Reaction in Acetonitrile–Glycol Mixtures. An Approach by a Concurrent Monodentate and Bidentate Solvation Model of the Halide Ion
Authors: Kondo Yasuhiko , Tanaka Kazuo , Tokura Niichiro
Published: July 2006

The rate constant of the reaction of methyl iodide with the bromide ion showed a characteristic dependence on the composition of solvent mixtures. In five solvent mixtures, i.e., acetonitrile–ethylene glycol, –1,2-propanediol, –1,3-butanediol, –1,4-butanediol, and –2,3-butanediol, its dependence was fairly well reproduced by the theoretical equations derived on the basis of the concept of the concurrent monodentate and bidentate solvation of the halide ion by glycol. In contrast, the rate constants in acetonitrile–diethylene glycol and –triethylene glycol mixtures were better reproduced by the modified theoretical equations allowing for a self-association of glycol.
Synthesis of 2-Amino-2,3-dideoxy-l-ribohexose
Authors: Sano Hiroshi , Tsuchiya Tsutomu , Ban Yoshihiro , Umezawa Sumio
Published: July 2006

2-Amino-2,3-dideoxy-l-glucose (1) was synthesized from 2-amino-2-deoxy-l-glucose (2). The synthesis was achieved without protection of the anomeric hydroxyl group throughout the reaction sequence. The masked derivative (9) of 1 was prepared from 2 by sequential N-methoxycarbonylation, benzylidene acetal formation, mesylation, displacement with iodide, and hydrogenolysis. Alkaline hydrolysis of the debenzylidenated product (10) led to ring contraction and yielded the 1,2-oxazolidinone derivative (11) of a furanose. Acidic hydrolysis of 11 underwent ring expansion and successfully gave 1.
Hetera-p-carbophane. VIII. The Change in Binding Sites of NMR Shift Reagents in Polyoxadioxo[n]paracyclophanes and Their Open-chain Analogs
Authors: Sakamoto Kazuhiko , Oki Michinori
Published: July 2006

A series of polyoxadioxo[n]paracyclophanes were prepared by condensation of polyethylene glycols with the corresponding 2,5-disubstituted p-phenylenediacetyl dichlorides under high dilution conditions. 1H NMR spectra of these compounds were recorded in the presence and absence of lanthanoid shift reagents and the results are compared with those of the open-chain analogs. The change in binding sites of the shift reagents is observed as the number of ethylenedioxy units increases, and the result is discussed from the standpoint of electronic and steric effects.
N-Halogen Compounds of Cyanamide Derivatives. VII. The Preparation and Amidination of 5-Ethoxy-Δ4-1,2,4-thiadiazolines
Authors: Fuchigami Toshio , Nonaka Tsutomu , Odo Keijiro
Published: July 2006

2-Methoxycarbonimidoyl and 2-amidino-3-imino-5-ethoxy-Δ4-1,2,4-thiadiazolines (I and II) were prepared by the reaction of potassium ethoxythiocarbonylcyanamide (III) with N-chloro compounds of O-methylisourea and guanidine. Δ4-1,2,4-Thiadiazoline, I reacted with aliphatic amine to give 2-amidino-Δ4,2,4-thiadiazolines and 1,3,5-triazines in the presence of both the free amines and amine hydrochlorides. The ring opening of Δ4-1,2,4-thiadiazoline, which finally results in the formation of 1,3,5-triazine, was found to be catalyzed mainly by a base and also by an acid.
Conformationally Stable 1-Substituted 1-Methyl-4-t-butyl-1-silacyclohexanes, a New Organosilicon System Suitable for Stereochemical Studies
Authors: Sakurai Hideki , Murakami Masashi
Published: July 2006

Ten 1-methyl-4-t-butyl-1-silacyclohexyl derivatives (C10H21Si–X, X=H, Cl, OCH(CH3)2, OCH3, OC(CH3)3, C6H5, p-Br–C6H4, p-Cl–C6H4, Si(CH3)2H, F) were synthesized and separated into conformationally stable cis and trans isomers. The stereochemistry of these compounds has been determined on the basis of NMR and GLC. They were found to behave stereochemically like acyclic optically active silanes.
Syntheses of 2-Amino-2,3-dideoxy-l- and -d-Ribohexose by Utilizing an O→N Acetyl Migration
Authors: Yamasaki Tetsuro , Kubota Yutaka , Tsuchiya Tsutomu , Umezawa Sumio
Published: July 2006

2-Amino-2,3-dideoxy-l- and -d-ribohexose (1l and 1d) were synthesized from 2-amino-2-deoxy-l- and -d-glucose, respectively, through a reaction sequence which involves 3-O→2-N acetyl migration of methyl 3,4,6-tri-O-acetyl-2-amino-2-deoxy-β-l- and -d-glucopyranoside (3l and 3d). A preparative method of methyl 4,6-di-O-acetyl-2-amino-2-deoxy-β-d-glucopyranoside (11d) is given.
Aminocyclitols. 34. Synthesis of Inosadiamine-1,4 Derivatives
Authors: Tadano Kinnichi , Shiratori Takaaki , Suami Tetsuo
Published: July 2006

Three new inosadiamine-1,4 derivatives have been prepared by nitromethane cyclization of a dialdehyde obtained by periodate oxidation of 1,4-di-O-methyl-(l,2,3,4,5/0)-5-acetamido-l,2,3,4-cyclopentanetetrol. The cyclization product was catalytically hydrogenated and subsequently acetylated to give three inosadiamine derivatives. Their structures were established by PMR spectra as myo-2,5, epi-1,4, and cis-inosadiamine-1,4 derivatives.
Reaction of Dimethylphenacylsulfonium Bromide with N-Nitrosoacetarylamides and Reactions of the Products with Nucleophiles
Authors: Shawali A Sami , Abdelhamid A Osman
Published: July 2006

The azo coupling of dimethylphenacylsulfonium bromides (I) with N-nitrosoacetanilides in nonaqueous solvents, and with diazotized aniline in aqueous media gave 2-bromophenylglyoxal 2-arylhydrazones (V) and the tetrazine (VI), respectively. V reacted with nucleophiles displacing the bromide. Treatment of V with bases gave VI via benzoylphenylnitrilimine (X). 1,3-Dipolar cycloadditions of X onto ethyl acrylate and acrylonitrile afforded the expected cycloadducts. The mechanisms of the reactions are outlined.
Micellar Activation of Nucleophilic Reactivity of Coenzyme A and Glutathione toward p-Nitrophenyl Acetate
Authors: Shinkai Seiji , Kunitake Toyoki
Published: July 2006

The reaction of coenzyme A(CoASH) and glutathione (GSH) with p-nitrophenyl acetate was studied in aqueous media at 30 °C. The reaction is highly accelerated in the presence of hydrophobic aggregates such as hydrophobic oligocations and CTABr micelles. Nonionic and anionic micelles were ineffective. The pKa of CoASH is lowered by 0.5 pKa unit in 2 mM of CTABr, while that of GSH is hardly affected. The second-order rate constant for CoASH is improved (290-fold) more than that of GSH (100-fold), relative to the nonmicellar system. Enhanced reactivities are efficiently suppressed by addition of KCl. These results are the first example of the marked activation of sulfhydryl coenzymes by the micellar microenvironment, and explicable by the concept of hydrophobic ion pairs: the coenzymes are bound onto the cationic micelle and the thiol anions form ion pairs with surfactant cations at the relatively hydrophobic environment of the micelle.
The N-Alkylation of Xanthine Derivatives with Trialkyl Phosphates
Authors: Tanabe Toshizumi , Yamauchi Kiyoshi , Kinoshita Masayoshi
Published: July 2006

The N-alkylation of xanthine, theophylline, and theobromine with trimethyl, triethyl, and triallyl phosphates in a weak alkaline aqueous solution is described. Especially, trimethyl phosphate converted these heterocycles to the corresponding N-methyl derivatives in good yields.
A Simple Method for the Synthesis of Lignan Skeleton. Syntheses of (±)-Parabenzlactone and (±)-Hinokinin
Authors: Asano Yuzo , Kamikawa Tadao , Tokoroyama Takashi
Published: July 2006

The reaction of 2-aryl-2-lithio-l,3-dithianes with 2-butenolide followed by quenching with benzyl halides gave lignan skeleton in fairly good yield.
Sulfoxonium Ylide Chemistry. VII. Reductive Cleavage of Dimethylsulfoxonium Allylides
Authors: Ide Junya , Kishida Yukichi
Published: July 2006

Reductive cleavage of dimethylsulfoxonium allylides with zinc in acetic acid or by hydrogenation over platinum at high pressure (120 atm) has been investigated. Reduction of dimethylsulfoxonium 3-ethoxycarbonyl-2-phenylallylide (1) with zinc gave predominantly ethyl 3-phenyl-3-butenoate (2) together with ethyl (E)-3-phenyl-2-butenoate (3) (90: 10). However, under the more acidic conditions (pH 2), 3 was the exclusive product. Hydrogenation of 1 over platinum afforded a mixture of 3 and ethyl 3-phenylbutanoate (4). Reduction of dimethylsulfoxonium 3-ethoxycarbonyl-2-phenyl-1-(phenylcarbamoyl)allylide (6) either with zinc or by hydrogenation gave ethyl (Z)-3-phenyl-4-phenylcarbamoyl-2-butenoate (7). Hydrogenation of dimethylsulfoxonium 1-benzoyl-3-ethoxycarbonyl-2-phenylallylide (9) at room temperature provided ethyl (Z)-3,5-diphenyl-5-oxo-2-pentenoate (10) and 4,6-diphenyl-2-pyrone (11), and at 80°C 11 and ethyl 3,5-diphenyl-5-oxopentanoate (12).
Studies on the Reacions of Bis(acetylacetonato)platinum(II) with Lewis Bases. II. Reaction with Pyridine Leading to Complexes Containing Uni- and Bis-Carbon Bonded Acetylacetonato Ligand(s).
Authors: Ito Takashi , Kiriyama Takashi , Nakamura Yoshiyuki , Yamamoto Akio
Published: July 2006

Heating a pyridine solution of [Pt(acac)2] (acac=2,4-pentanedionato-O,O′) at 100°C afforded central C-bonded complexes, [Pt(acac)(γ-acac)py], 1, and [Pt(γ-acac)2py2], 2 (γ-acac=2,4-pentanedionato-C3). Complexes 1 and 2 were isolated and characterized by means of elemental analysis, infrared and 1H- and 13C-NMR spectroscopy. Heating 1 in pyridine yielded 2, and conversely, heating 2 in CDCl3 yielded 1. All these reactions were monitored by 1H-NMR spectroscopy and were found to obey the first-order rate law. From the rate constants at various temperatures, activation parameters were calculated for each reaction. Existence of isokinetic relationship among these three reactions suggests the presence of a common reaction intermediate. Observation of the variable temperature 1H-NMR spectra of [Pd(acac)(γ-acac)py] in pyridine suggests that the activated intermediate may be a species having an oxygen-bonded unidentate acac ligand (“dangling” enolate ligand).
The Constitution of NaPO3–Cr2O3 Melts
Authors: Watanabe Makoto , Sato Shoji , Saito Hajime
Published: July 2006

Glassy and crystalline thermal products were made by heating a mixture of sodium metaphosphate glass and chromium(III) oxide with P/Cr ratios in the range from 1.0 to 300 at 1000 °C for 3 h in a platinum crucible and by then rapidly quenching the resulting melt. The crystalline substances were present in the products with P/Cr ratios smaller than 50 and were, except for chromium(III) oxide, an unknown substance and chromium(III) tripolyphosphate. The colorimetric determination and the measurement of the average chain length of polyphosphate anions present in the water-soluble parts of the products with P/Cr ratios larger than 50 showed that chromium(III) oxide reacts with sodium metaphosphate glass to make Cr–O–P linkages. Assuming that the glass has P–O–P, P-O−, Cr–O–P, and Cr–O− linkages, a theoretical treatment of the degree of polymerization of condensed phosphates were made and compared with the data. It was concluded that the most reasonable chemical structure of the glassy thermal products of the NaPO3–Cr2O3 system is Cr(OP)3.
Synthesis of Dihalogenobis(2-pyridinethiolato)tin(IV) by the Oxidative Addition of Bisulfide to Tin(II) Halides—Consideration on the Coordination Structure
Authors: Masaki Mitsuo , Matsunami Satoshi
Published: July 2006

The reaction of di-2-pyridyl disulfide with tin(II) halides was found to give dihalogenobis(2-pyridinethiolato)-tin(IV). The oxidative addition reaction was successfully extended to the preparation of other dihalogenodi-thiolatotin(IV) complexes. Dichlorobis(2-pyridinethiolato)tin(IV) was also prepared by the reaction of 2(1H)-pyridinethione with tin(IV) chloride and proposed to be a monomeric, octahedral complex with a four-membered (Sn, S, C, and N) chelate ring from its molecular weight and IR spectral data. Dichlorobis(2-quinolinethiolato)tin(IV) could be isolated similarly as a stable complex. However, attempts to isolate the dichlorodithiolatotin(IV) in which an intramolecular chelation seems hardly possible were unsuccessful. The great stability of bis(2-pyridinethiolato)- and bis(2-quinolinethiolato)-dihalogenotin(IV) could be ascribed to the intramolecular four-membered chelate ring formation for the six-coordination of tin atom.
Dielectric Behavior of N-Methylacetamide
Authors: Itoh Koichi , Sato Hiroshi , Takahashi Hiroaki , Higasi Keniti
Published: July 2006

The dielectric constants and losses of liquid N-methylacetamide were measured in the frequency range 0.356–2.10 GHz at 31.4 °C. The result provides a definitive evidence for the validity of the simple Debye equation for the dielectric relaxation process of liquid N-methylacetamide.
Carbonylation of Dienes and Diols in the Presence of Copper(I) Carbonyl Catalysts
Authors: Souma Yoshie , Iyoda Jun , Sano Hiroshi
Published: July 2006

Dienes and diols having carbon numbers of 6 to 12 reacted with carbon monoxide to give mixtures of lactones, dicarboxylic acids and monocarboxylic acids in the presence of copper(I) carbonyl catalysts at room temperature and at 1 atm of carbon monoxide. Dienes and diols having carbon numbers larger than 10 gave isomers of dicarboxylic acid, the main component of which was tetramethyl-substituted tertiary carboxylic acid. The yield increased for an increase of the carbon number. All starting materials gave mixtures of 1,4- and 1,5-lactones. Larger amounts of the lactones were obtained from diols than from dienes. Cyclic monocarboxylic acid and saturated monocarboxylic acid were obtained by the carbonylation of 1,7-octadiene. The appropriate reaction temperature of the dienes and diols was 0–10 and 20–30 °C respectively.
Layered Compounds. XXXIV. Molecular and Crystal Structure of a Polycyclic Compound from Novel Cycloaddition Reaction of Triple-layered Anthracenophane
Authors: Toyoda Toshihiro , Iwama Akio , Otsubo Tetsuo , Misumi Soichi
Published: July 2006

An unusual Diels-Alder reaction was observed to give intramolecular cycloadducts during the syntheses of triple-layered cyclophanes containing anthracene nucleus. The structure of the product was determined by spectral and X-ray crystal analyses. The crystal is monoclinic, P21/c, with a=15.896, b=8.937, c=18.575 Å, β=120.31°, Z=4. The crystal structure was determined by the direct method using the MULTAN program and refined by the block-diagonal least-squares method to an R index of 0.081. The structure of the molecule is fairly strained.
Note on the Use of Linear Free Energy Relationships in Heterogeneously Catalyzed Reactions
Authors: Kieboom A P G
Published: July 2006

A critical examination of the use of linear free energy relationships in the study of the mechanism of heterogeneously catalyzed reactions is presented in the case of the ruthenium catalyzed hydrogenation of monoalkylbenzenes reported in the literature. It is concluded that the use of both electronic and steric substituent parameters leads to a quite different mechanistic interpretation as compared to the statements made before in the literature on the basis of just the electronic substituent parameter.
Infrared Spectra of Tribromochloro-p-benzoquinone and Its Anion Radical
Authors: Iida Yôichi
Published: July 2006

A chemically-stable anion radical salt of tribromochloro-p-benzoquinone was synthesized. The infrared spectrum of the anion radical was examined together with its neutral molecule.
Preparation and Circular Dichroism of Cyanoamminebis[(R)-propylenediamine]cobalt(III) Complexes
Authors: Kashiwabara Kazuo , Suzuki Shoichi
Published: July 2006

Three new complexes, trans-, cis-Λ-, and cis-Δ-[Co(CN)(NH3)(R-pn)2]2+(pn=propylenediamine) were prepared. The geometrical structure was determined on the basis of 1H NMR spectra. The optical isomers were characterized from the circular dichroism spectra.
The 13C NMR Spectra of Several 4-Amino-3-penten-2-ones and Their Palladium Complexes
Authors: Senda Yasuhisa , Kasahara Akira , Suzuki Akio , Izumi Taeko
Published: July 2006

A 13C NMR study of several 4-amino-3-penten-2-ones and their palladium chelate complexes is presented. The resonances of the carbonyl carbons of these complexed molecules moved upfield by about 20 ppm relative to the free ligands, while no significant shifts were observed for those of carbons bearing the amino groups.
Sulfoxonium Ylide Chemistry. VI. A Convenient Method for Synthesizing 1-Substituted 4-Phenyl-3-pyrrolin-2-ones
Authors: Ide Junya , Yura Yasuo
Published: July 2006

Synthesis of 1-substituted 4-phenyl-3-pyrrolin-2-ones (2) from dimethylsulfoxonium 3-ethoxycarbonyl-2-phenylallylide (1) and various primary amines is described.
Phase Diagram of the Pyrene-Picryl Chloride System
Authors: Bando Masaki , Matsunaga Yoshio
Published: July 2006

A differential scanning calorimetric study of the pyrene–picryl chloride system has revealed five molecular compounds with mole ratios of 1: 1, 4: 3, 2: 1, 3: 1, and 4: 1 respectively.
Charge-carrier Drift Mobility in Pyrene Single Crystals
Authors: Suzuki Akira , Inokuchi Hiroo , Maruyama Yusei
Published: July 2006

The charge-carrier drift mobility in highly pure pyrene single crystals was measured. Observed values were (3.8±0.1) ×10−3 cm2 V−1 s−1 for electrons and (3.3±0.4) ×10−3 cm2 V−1 s−1 for holes at 345 K. The mobilities increased with the temperature between 333–374 K with an activation energy of 0.43±0.01 eV for electrons.
Observation of the Scale Formed on Nickel in Nitrogen Oxide
Authors: Takasu Yoshio , Maru Shun-ichi , Matsuda Yoshiharu
Published: July 2006

The state of the scale formed on nickel in nitrogen oxide was examined. Its characteristics are summarized as follows: (1) remarkable oxidation of the grain boundary, (2) the formation of a large amount of lattice defects, and (3) unequal oxidation behaviors for the various crystal planes.
Photoreactions of Flavanones
Authors: Nakashima Ruka , Okamoto Kazuaki , Matsuura Teruo
Published: July 2006

On irradiation in benzene, 5,7-dimethyl-4′-methoxyflavanone gave a bis-flavanone V, while in 2-propanol it was largely recovered. Irradiation of 4′-methoxyflavanone in benzene and 2-propanol yielded the corresponding chalcone and pinacols, respectively. 5,7,4′-Trimethoxyflavanone was relatively inert to photolysis in benzene, but gave a complex mixture of products in 2-propanol.
The Photochemical Synthesis of 5-Aryl-7,12-benz[a]anthracenediones from 1,4-Naphthoquinones and 1,1-Diarylethylenes
Authors: Maruyama Kazuhiro , Otsuki Tetsuo , Mitsui Kiichiro
Published: July 2006

By the photolysis of the benzene solution of a variety of 2,3-disubstituted (halogeno, methoxy, and acetoxy) 1,4-naphthoquinones, 1, and 1,1-diarylethylenes, 2, 5-aryl-7,12-benz[a]anthracenediones, 3, are obtained in fairly good yields (22–68%).
The Structure of Hamayne, a New Alkaloid from Crinum asiaticum L. var. japonicum Baker
Authors: Ochi Masamitsu , Otsuki Hitoshi , Nagao Kosho
Published: July 2006

The structure of hamayne isolated from the fruit of Crinum asiaticum L. var. japonicum Baker was established to be O-demethylcrinamine (IV) on the basis of spectral and chemical evidence.
Nature of Oxygen Species Incorporated into Acrylaldehyde in Vapor-Phase Oxidation of Propylene over Supported Copper Catalyst
Authors: Akimoto Masamichi , Akiyama Masao , Echigoya Etsuro
Published: July 2006

The oxidation of propylene with Cu2O as active phase for acrylaldehyde formation gave no acrylaldehyde in contrast to the fully oxidized CuO–SiC. However, CuO–SiC from which adsorbed oxygen species was eliminated gave rise to the formation of a negligible amount of acrylaldehyde. The presence of molecular oxygen species adsorbed on the CuO–SiC was shown by the desorption of oxygen and the isotopic mixing reaction of 16O–18O. The adsorbed oxygen (possibly molecular oxygen species) seems to be necessary as oxygen incorporated into acrylaldehyde. Agreement of the ratio of 18O/16O in acrylaldehyde formed by the oxidation with oxygen containing 18O over Cu216O with that of 18O/16O in the reaction mixture supports the role of adsorbed oxygen species. The presence of O2− over Cu2O during the course of oxidation was confirmed by the formation of furan and maleic anhydride in the co-oxidation with butadiene. The results were discussed in relation to the structure of the catalyst suitable for selective oxidation, the incorporation of oxygen atom via electronegative oxygen species adsorbed being proposed.
ENDOR Studies of the Hyperfine Interaction of Phenylgalvinoxyl Radicals in Solution
Authors: Mukai Kazuo , Kamata Takashi , Tamaki Toshiko , Ishizu Kazuhiko
Published: July 2006

The ENDOR spectra of ten kinds of phenylgalvinoxyl derivatives in solution have been observed, and the hyperfine splitting constants have been determined. The formally equivalent four meta ring protons of the galvinoxyl skeleton in the phenylgalvinoxyl radical become magnetically nonequivalent in two groups of two. This behavior may be explained by assuming that splittings arising through pure spin polarization, or through mixed hyperconjugation and spin polarization, are different for syn and anti meta ring protons of the phenylgalvinoxyl radical. A similar effect has been observed in the ENDOR spectra of other phenylgalvinoxyl derivatives. In radicals with a large substitution group at the meta or para position of the phenyl ring, the galvinoxyl skeleton twists unsymmetrically on either side; thus, all or three among the four meta ring protons become magnetically nonequivalent. The solvent dependence of the ENDOR spectra of the phenylgalvinoxyl radicals constituted strong evidence for the importance of the solvent in fixing the conformation and symmetric property of the radical molecules. The proposed analyses of the ENDOR spectra were also supported by the McLachlan Molecular Orbital calculations.
Equilibrium Spreading Pressure of the Mixed System of Normal Long Chain Fatty Acids
Authors: Fujii Kozo , Yoshino Seiji , Motomura Kinsi , Nakamura Makoto , Matuura Ryohei
Published: July 2006

Equilibrium spreading pressure were measured at various compositions and temperatures for mixed systems of tridecanoic acid-myristic acid, myristic acid-pentadecanoic acid, and pentadecanoic acid-palmitic acid, and thermodynamical treatment of these data with respect to the equilibrium between crystal and monolayer was performed. By evaluating the equilibrium composition of monolayer phase from the measured curve of equilibrium spreading pressure vs. composition of solid phase, the phase diagram was constructed. It was found that the equilibrium curve has a maximum point where the solid and monolayer phases have the same composition and a point where the solid phase is in equilibrium with two monolayer phases. The partial molar enthalpy change accompanied by the phase transition from solid to monolayer were found to be dependent on the composition.
Catalytic Isotope Exchange Reaction between Deuterium Gas and Water Pre-Adsorbed on Platinum/Alumina
Authors: Iida Itsuo , Kato Junko , Tamaru Kenzi
Published: July 2006

The catalytic isotope exchange reaction between deuterium gas and the water pre-adsorbed on Pt/Al2O3 was studied. At reaction temperatures above 273 K, the exchange rate was proportional to the deuterium pressure and independent of the amount of adsorbed water, which suggests that the rate determining step is the supply of deuterium from the gas phase. Its apparent activation energy was 38 kJ mol−1. Below freezing point of water, the kinetic behaviour was different from that above freezing point. At higher deuterium pressures the rate dropped abruptly at 273 K. Below the temperature the apparent activation energy was 54 kJ mol−1 and the exchange rate depended not on the deuterium pressure but on the amount of the pre-adsorbed water. At lower pressures, however, the kinetic behaviour was the same as that above 273 K, till the rate of the supply of deuterium from the gas phase exceeded the supply of hydrogen from adsorbed water to platinum surface.

These results suggest that below 273 K the supply of hydrogen is markedly retarded, the state of the adsorbed water differing from that above 273 K. It was also demonstrated that when the adsorbed water is in the state of capillary condensation, the exchange rate becomes very small.
Stereochemical Studies of Elimination Reactions of 2-Bromobutane and 2,3-Dibromobutane over Bivalent-Ion Exchanged Silica Gels
Authors: Aoki Yukio , Misono Makoto , Yoneda Yukio
Published: July 2006

Elimination reactions of 2-bromobutane and 2,3-dibromobutane over silica gels in which silanol protons on the surface were exchanged with bivalent ions such as Ba(II), Ca(II), Mg(II), and Ni(II) have been investigated. Dehydrobromination of 2-bromobutane was found to proceed mainly with syn elimination. Debromination by anti mode and non-stereospecific dehydrobromination were observed for 2,3-dibromobutane. The catalytic activities of these silica gels exhibit reversed volcano-type patterns when they are plotted against the electronegativity of metal ion together with those of alkali-ion exchanged silica gels. Reaction intermediates consistent with the stereochemistry observed are a s-butyl cation and a bromonium ion, respectively for 2-bromobutane and 2,3-dibromobutane.
Microwave Spectrum of (Chloromethyl)germane
Authors: Nakagawa Jun , Hayashi Michiro
Published: July 2006

In order to determine the molecular structure and barrier to internal rotation of the GeH3 group, the microwave spectra of (chloromethy)germane and its deuterated species ClCH2GeD3 have been investigated. From splittings of the spectra due to the first excited GeH3 torsional state, the barrier to internal rotation was determined to be 1740±30 cal/mol. Assuming the cylindrical symmetry of the C–Cl bond, the quadrupole coupling constant was determined to be χzz=−74.7 MHz for the 35ClCH274GeH3 species.
The Crystal and Molecular Structure of Naphthanthrone
Authors: Fujisawa Shoji , Oonishi Isao , Aoki Junji , Iwashima Satoshi
Published: July 2006

The crystals of naphthanthrone(C19H10O) are orthorhombic, with the P212121 space group and these lattice constants: a=17.345(17), b=3.973(13), c=17.392(14) Å, and Z=4. The structure was solved by the Patterson method and refined by a block-diagonal least-squares program to give an R-value of 0.085 on the basis of the 897 observed reflections collected by Weissenberg photographs. The molecule is planar within the limits of experimental error and has an approximate symmetry of mm. The molecules are stacked face-to-face by van der Waals forces along the b-axis. The interplanar spacing is 3.50 Å.
Theoretical Analysis of Optical Rotatory Power of Methylcyclohexanone with Treatment of Conformational Equilibria
Authors: Nakamura Tomoyasu , I’Haya Yasumasa J
Published: July 2006

Optical rotational strength for the n-π* transition of (R)-3-methylcyclohexanone is calculated by the CNDO/2 and INDO methods and compared with the observed values at 81 and 300 K, taking account of conformational equilibria. The conformer species are chosen so that they have minimal potential energies, the potential energy surface being estimated with a non-bonded interaction approximation. Excited state wave functions are improved by a model potential method. The ratio of the rotational strengths at 81 and 300 K, each of them being calculated as a statistical average of the rotational strengths of four conformers, is in good agreement with the corresponding observed value.
Carbon-13 and Proton Nuclear Magnetic Resonance Spectra of Methylmercury Nitrate in Strong Acids
Authors: Kawasaki Yoshikane , Aritomi Mitsutoshi , Iyoda Jun
Published: July 2006

Proton and carbon-13 nuclear magnetic resonance spectra and Raman spectra of some methylmercury compounds, CH3HgX, were measured. The spin-spin coupling constants, 2J(199Hg–H) and 1J(13C–H) of methylmercury nitrate in some strong acids were found to increase when the proton resonance of the methyl group attached to the mercury shifts to lower magnetic field. It was also found that the C–H stretching bands of the methyl group shift to higher frequency in the strong acids. The results are explained by an increase of the effective positive charge on the mercury. As has been observed in other alkylmercury compounds, the spin-spin coupling constant between directly bonded mercury and carbon nuclei, 1J(199Hg–C),of some methylmercury compounds in organic solvents increased with the geminal spin-spin coupling constant, 2J(199Hg–H). The 1J(199Hg–13C) value of methylmercury nitrate in strong acids was found to decrease, whereas the 2J(199Hg–H) values increased in these media. The lowering of the mercury-carbon bond strengths in the strong acids, which was revealed from the mercury-carbon stretching frequency in the Raman spectra, is considered one possible reason for the decrease of the 1J(199Hg–13C) value.
Template-Directed Synthesis of Oligonucleotide. Condensation of Nucleotide in the Presence of Polystyrene-Supported Neutral Oligonucleotide Derivative
Authors: Shimidzu Takeo , Imai Akio
Published: July 2006

A template-directed synthesis of oligonucleotide in the presence of polystyrene-supported neutral oligonucleotide derivative was studied. The oligonucleotide which has the sequence of the complementary base with the template, the neutral oligonucleotide derivative, yielded with a considerable amount, when the template with degree of oligomerization of 4 was used.
Complex Formation of Crosslinked Poly(4-vinylpyridine) Resins with Copper(II)
Authors: Nishide Hiroyuki , Deguchi Jichio , Tsuchida Eishun
Published: July 2006

Poly(4-vinylpyridine) was crosslinked with 1,4-dibromobutane, The obtained resin (DBQP) formed a stable complex with Cu2+, and the adsorption capacity of DBQP varied with the degree of crosslinking. The complex, formation of DBQP with Cu2+ was studied by examining the adsorption equilibrium and the spectroscopic measurement. The resin complex seems to be formed via no step-by-step mechanism, and the stability constant was appreciably large in comparison with those of non-crosslinked polymers and of a monomeric analogue. In the highfy crosslinked resins, the ligand-field is relatively weak and the stability of the Cu2+ complex is decreased.
Crystal Structures of Bis[N-(3-methoxysalicylidene)isopropylaminato]nickel(II) (Brown Room Temperature Phase) and -cobalt(II)
Authors: Ashida Tamaichi , Iwata Suteo , Yamane Takashi , Kakudo Masao , Takeuchi Akira , Yamada Shoichiro
Published: July 2006

The crystal structures of two Schiff base complexes, bis[N-(3-methoxysalicylidene)isopropylaminato]nickel (II) and -cobalt(II), have been determined. Ni complex: brown, room temperature phase, monoclinic, P21/c, a=21.089, b=7.254, c=14.386 Å, β=98.40°, Z=4, final R=0.076. Co complex: red, triclinic, P\bar1, a=22.699, b=7.395, c=14.099 Å, α=107.78, β=99.03, γ=93.75°, Z=4, final R=0.13. In both crystals the metal ions have distorted tetrahedral coordinations. The two crystals are roughly isostructural, although appreciable differences exist in both of the molecular and crystal structures. The Co complex gives a unique example of the methoxy group which sticks out nearly perpendicularly from the phenyl plane.
The Preparation and Characterization of Isomers of (Amino acidato)(iminodiacetato)nitrocobaltate(III)(1–) Complexes
Authors: Yamamoto Yukihiro , Kaizaki Sumio , Shimura Yoichi
Published: July 2006

Three geometrical isomers of fac(ida)-[Co(NO2)(gly)(ida)]− have been prepared and optically resolved (gly=glycinato(1–) and ida=iminodiacetato(2–) ligand), and their configurations were determined from the visible and ultraviolet absorption, and circular dichroism spectra. A diastereomeric pair was obtained for the corresponding l-alaninato, l-serinato, or l-prolinato complex.
Hydrothermal Synthesis of Some Varieties of Zircon
Authors: Nakai Izumi , Shima Tetsuo , Izawa Mihoko , Nagashima Kozo
Published: July 2006

Some varieties of zircon which contain yttrium, niobium, and phosphorus in solid solution have been synthesized at temperatures 500–550 °C and under pressures 700–1000 kg/cm2. In zircon containing yttrium, the unit cell constants a and c increase with increase in yttrium content up to 70 mol%. From IR and TGA studies, a valence compensation accompanying the substitution of yttrium is assumed to be effected by a concomitant substitution of OH for O sites, and the variety is represented by a formula (Zr,Y)Si(O,OH)4. On the other hand, the substitution of Nb5+ for Zr4+ is followed by a decrease in the cell constants. Zircon phase did not form from starting materials with more than 20 mol% of niobium content. From the syntheses of zircon containing both yttrium and niobium, the formula (Zr,Y,Nb) Si(O,OH)4 is found to be appropriate for naegite. An attempt was made to synthesize some solid solutions between zircon and xenotime. The unit cell constant c of the products is found to decrease with the substitution of PO4 for SiO4.
Syntheses of d-Arabinofuranosyl and 2′-Deoxy-d-ribofuranosyl Pyrazolecarboxamides
Authors: Makabe Osamu , Yajima Jutaro , Umezawa Sumio
Published: July 2006

Several d-arabino- and 2′-deoxy-d-ribonucleosides of carbamoylpyrazoles were synthesized by an acid-catalyzed fusion reaction of 1-O-acetyl derivatives of the corresponding sugars with pyrazole derivatives. Spectral evidences for their N-glycosylation sites and anomeric configurations were presented.
Synthesis of Corticotropin Peptides. X. The Synthesis of ACTH(1–18)–OH, ACTH(1–18)–NH2 and ACTH(1–19)–NH2
Authors: Inouye Ken , Shinozaki Fusako , Kanayama Makoto , Otsuka Hideo
Published: July 2006

The final coupling, deprotection and purification processes for the synthesis of octadecapeptides, H–Ser–Tyr–Ser–Met–Glu–His–Phe–Arg–Trp–Gly–Lys–Pro–Val–Gly–Lys–Lys–Arg–Arg–OH(I) and H–Ser–Tyr–Ser–Met–Glu–His–Phe–Arg–Trp–Gly–Lys–Pro–Val–Gly–Lys–Lys–Arg–Arg–NH2 (II), corresponding to the first eighteen amino acid residues of corticotropin (ACTH) are described, in which the N-hydroxysuccinimide ester of the N-terminal decapeptide derivative is coupled with the C-terminal octapeptide and octapeptide amide derivatives to give the two protected end products. The same decapeptide active ester is also utilized to the synthesis of a nonadecapeptide, H–Ser–Tyr–Ser–Met–Glu–His–Phe–Arg–Trp–Gly–Lys–Pro–Val–Gly–Lys–Lys–Arg–Arg–Pro–NH2 (III), identical with the first nineteen amino acid residues of ACTH. The in vivo steroidogenic potencies of the synthetic peptides are compared with that of the synthetic human ACTH (αh-ACTH) as reference to show that the relative potencies of I, II, and III vs. αh-ACTH are 0.14, 0.48, and 0.47, respectively, as estimated on a molar basis.
Synthesis of Corticotropin Peptides. XIII. The Synthesis of a Hexacosapeptide and a Heptacosapeptide Corresponding to the First Twenty-six and Twenty-seven Amino Acid Residues of Corticotropin (ACTH)
Authors: Inouye Ken , Sumitomo Yoshie , Shin Masaru
Published: July 2006

The syntheses are described of a hexacosapeptide H–Ser–Tyr–Ser–Met–Glu–His–Phe–Arg–Trp–Gly–Lys–Pro–Val–Gly–Lys–Lys–Arg–Arg–Pro–Val–Lys–Val–Tyr–Pro–Asn–Gly–OH (I) and a heptacosapeptide H–Ser–Tyr–Ser–Met–Glu–His–Phe–Arg–Trp–Gly–Lys–Pro–Val–Gly–Lys–Lys–Arg–Arg–Pro–Val–Lys–Val–Tyr–Pro–Asn–Gly–Ala–OH (II) corresponding to the first twenty-six and twenty-seven amino acid residues, respectively, of corticotropin (ACTH), in which a new protecting group 1-methylcyclohexyloxycarbonyl (Mhoc) is utilized for the temporary protection of the ε-amino function of lysines. The in vivo steroidogenic potencies of the synthetic peptides I and II are compared on a molar basis with those of ACTH(1–18)-NH2 and synthetic human ACTH (αh-ACTH) to demonstrate that the relative potencies of I and II vs. ACTH(1–18)–NH2 are 2.3 and 2.3–3.8, respectively, and those vs. αh-ACTH are 1.1 and 1.1–1.8, respectively.
A Study of the 1,3,5-Trialkylbenzenes with Aluminum Chloride-Hydrogen Chloride Systems
Authors: Nambu Nobuyoshi , Hiraoka Nobumoto , Shigemura Kenji , Hamanaka Sawako , Ogawa Masaya
Published: July 2006

The “red-oil” complex layers of systems of 1,3,5-trialkylbenzenes (Me3B, Et3B, i-Pr3B, and s-Bu3B) with AlCl3–HCl were prepared and studied by means of 1H NMR and 13C NMR spectroscopy. The results show that the 2,4,6-trialkylbenzenium ion is evidently formed in the complex layer of the AlCl3–HCl system, much as in other super acid systems, and that those ions from i-Pr3B and s-Bu3B are substantially stable, even at room temperature. The molar ratios of i-Pr3B and s-Bu3B to HAl2Cl7 are almost 1. On the other hand, the molar ratios of Me3B and Et3B to HAl2Cl7 are 4.5 and 1.9 respectively. These two complex layers are considered to be formed by both 1,3,5-trialkylbenzene and its protonated product, and to be in a certain equilibrium state as a result of proton exchange at room temperature.
Coenzyme Models. VIII. Reduction of the Schiff Base of Pyridoxal Analogs by 1,4-Dihydronicotinamide
Authors: Shinkai Seiji , Shiraishi Sumihiro , Kunitake Toyoki
Published: July 2006

Reduction of Schiff bases by 1-benzyl-1,4-dihydronicotinamide (BzlNH) was performed in refluxing methanol. Protonated imines such as N-(p-nitrobenzylidene)benzylamme hydrochloride (1H+) and N-(4-nitrosalicylidene)benzylamine hydrochloride (1(OH)H+) were reduced to the corresponding aminomethyl derivatives. The NMR product analysis for the reaction of BzlNH and 1H+ in refluxing ethanol-d established that the solvent deuteron was not incorporated into the aminomethylene product. 1(OH), unprotonated species, was partially reducible, whereas 1 was totally unreactive. The facile reduction of 1 occurred in the presence of several amine hydrochlorides (NEt3·HCl, imidazole hydrochloride, N,N,N′,N′-tetramethylethylenediamine dihydrochloride). These results show that the ortho hydroxyl group of 1(OH) facilitates imine reduction not only by polarization of the Schiff base via hydrogen bonding but also by proton transfer. The relative reactivity of the Schiff base to the BzlNH reduction is: 1H+, 1+NEt3·HCl≥1(OH)H+>1(OH)>1(unreactive) This order is similar to that found in “trans-Schiffization” between semicarbazide and the Schiff base of pyridoxal and its analogs, as reported by Gordes and Jencks.