bluuebunny/crossref_metadata_2025 huggingface dataset:
ORGANIC PEROXIDES: III. REACTIONS OF DIALKYL PEROXIDES WITH ORGANOLITHIUM AND ORGANOMAGNESIUM COMPOUNDS
Authors: Baramki G. A. , Chang H. S. , Edward J. T.
Published: May 2006

Optimum conditions for obtaining arylalkyl ethers from the reactions of aryl-lithium or -magnesium compounds with dialkyl peroxides have been investigated. The reactions are considered to take place by ionic or four-center mechanisms.
METALLO-ORGANIC COMPOUNDS CONTAINING METAL–NITROGEN BONDS: PART II. SOME DIALKYLAMINO DERIVATIVES OF Nb(V) AND Nb(IV)
Authors: Bradley D. C. , Thomas I. M.
Published: May 2006

Reactions involving niobium pentachloride and lithium dialkylamides (LiNR2, where R = Me, Et, Prn, Bun) led to considerable reduction of niobium to Nb(IV) as the length of the alkyl chains increased. Nb(NMe2)5 was isolated by sublimation but distillation of the other products gave tetrakis-(dialkylamino)-niobium(IV) compounds. Steric factors are apparently responsible for the low stability of pentakis-(dialkylamino)-niobium(V) compounds. The smaller steric effects of —NMeBun and piperidino groups allowed the isolation of pentakis derivatives. The thermal decomposition of Nb(NMeBun)5 gave mainly Nb(NMeBun)4 with some BunN=Nb(NMeBun)3. Steric effects were also revealed in the replacement of —NMe2 groups in Nb(NMe2)5 by —NEt2 groups and in replacement of —NEt2 groups in Nb(NEt2)4 by piperidino groups.
THE ALKALOIDS OF STEMONA SESSILIFOLIA
Authors: Edwards O. E. , Feniak G. , Handa K. L.
Published: May 2006

The alkaloids tuberostemonine, oxotuberostemonine, and the new base tuberostemonine-A have been isolated from the rhizomes of Stemona sessilifolia. Tuberostemonine has been oxidized to oxotuberostemonine and tuberostemonine-A has been related to tuberostemonine through common oxidation products. Study of transformation products of tuberostemonine has enabled assignment of partial structure V to the alkaloid.
THE SYNTHESIS OF ACETAMIDO-DEOXY KETOSES BY ACETOBACTER SUBOXYDANS: PART III
Authors: Jones J. K. N. , Perry M. B. , Turner J. C.
Published: May 2006

1-Acetamido-1-deoxy-D-arabinitol, 1-acetamido-1-deoxy-D-ribitol, and 1-acetamido-1-deoxy-D-mannitol were synthesized and characterized. Microbiological oxidation of 1-acetamido-1-deoxy-D-arabinitol and 1-acetamido-1-deoxy-D-ribitol gave the crystalline acyclic 2-pentuloses 5-acetamido-5-deoxy-D-threo-pentulose and 5-acetamido-5-deoxy-L-erythro-pentulose respectively.
THE SYNTHESIS OF MERCAPTOINDOLES
Authors: Piers E. , Haarstad V. B. , Cushley R. J. , Brown R. K.
Published: May 2006

The 4-, 5-, 6-, and 7-mercaptoindoles have been prepared via the Reissert condensation of the isomeric benzylthio-o-nitrotoluenes. The latter were synthesized by diazotization of the corresponding 2-nitrotoluidines or by direct displacement of the halogen atom in monobrominated o-nitrotoluenes with the benzylmercapto group using dimethylformamide as solvent.
THE RAMAN SPECTRA OF SULPHURIC, DEUTEROSULPHURIC, FLUOROSULPHURIC, CHLOROSULPHURIC, AND METHANESULPHONIC ACIDS AND THEIR ANIONS
Authors: Gillespie R. J. , Robinson E. A.
Published: May 2006

The Raman spectra of sulphuric acid, deuterosulphuric acid, chlorosulphuric acid, and methanesulphonic acid have been redetermined, and the spectrum of fluorosulphuric acid measured for the first time. The spectra of fluorosulphuric acid – sulphuric acid, chlorosulphuric acid – sulphuric acid, and fluorosulphuric acid – arsenic trifluoride mixtures have also been measured. The spectra of the hydrogen sulphate, deutero sulphate, fluorosulphate, chlorosulphate, and methanesulphonate anions have been obtained in various solvents. Frequencies are assigned to the normal modes of vibration of all these acids and their anions and the assignments are compared with those of previous workers.
DEUTERIUM ISOTOPE EFFECTS IN ABSTRACTION OF HYDROGEN ATOMS FROM PHENOLS
Authors: Bird R. A. , Harpell G. A. , Russell K. E.
Published: May 2006

The effect of six deuterated phenols on the rate and degree of polymerization of styrene has been studied. The rate and degree of polymerization are decreased by deuterated phenols to a much less extent than by the corresponding phenols. Approximate transfer constants are estimated, and it is found that the transfer constant for hydrogen abstraction from the deuterated phenol is less than 0.2 of the transfer constant for the normal phenol. The rates of reaction of 2,2-diphenyl-1-picrylhydrazyl with three deuterated phenols have been determined. The rate constants for deuterated 2,6-di-t-butylphenol and 4-bromophenol are less than 0.15 of those for the corresponding phenols, but the isotope effect appears to be small with 4-nitrophenol.
STEREOCHEMICAL STUDIES: IV. ACID-CATALYZED EQUILIBRATION OF α- AND β-FORMS OF 3-ALKOXY-4-OXA-5α-CHOLESTANES. THE ANOMERIC EFFECT
Authors: Edward J. T. , Puskas I.
Published: May 2006

The α- and β-anomers of 3-methoxy-, 3-isopropoxy-, 3-cyclohexyloxy-, and 3-phenoxy-4-oxa-5α-cholestane were separated by chromatography on alumina. The configurations of the anomers were assigned from a consideration of their optical rotations. Acid-catalyzed equilibration of the 3-alkoxy anomers favored formation of the axial isomer, the proportions of α- to β-forms being about 7:3. 2α-Phenoxy-4-oxa-5α-cholestane in acid solution was in equilibrium with phenol and 4-oxa-5α-cholest-2-ene.
DERIVATIVES OF MONOGERMANE: PART II. PREPARATION AND PROPERTIES OF GERMYL PSEUDOHALIDES AND RELATED COMPOUNDS
Authors: Srivastava T. N. , Griffiths J. E. , Onyszchuk M.
Published: May 2006

Germyl isocyanate, isothiocyanate, and acetate have been prepared in almost quantitative yield by the interaction of germyl bromide with silver cyanate, thiocyanate, and acetate, respectively. Some of the physical properties of these new germyl derivatives are reported, and their thermal decompositions at moderate temperatures are described. The reaction of germyl bromide with silver oxide or carbonate produces germanium (II) hydride and water instead of digermoxane. Germyl bromide reacts with silver nitrite, forming germane, nitrous oxide, and nitric oxide as the only volatile products.
A CALCULATION OF THE H2O2 MOLECULE BY THE LCAO–MO–SCF METHOD
Authors: Amako Yoshito , Giguère Paul A.
Published: May 2006

The electronic structure of the hydrogen peroxide molecule in three different configurations, namely the cis, the trans, and the non-planar or skew forms, were calculated according to the LCAO–MO–SCF approximation. All the electrons were considered except those of the K-shell of the oxygen atoms. The orbitals of these atoms are essentially of the sp3 hybrid type. It was shown that the skew form of the molecule with an azimuthal angle Φ of about 120° is the most stable, due mainly to conjugation of the σ5 and σ6 orbitals of the oxygen atoms with the other molecular orbitals. On the contrary, in the cis and trans forms these two orbitals are non-bonding. Because of the approximate nature of the treatment, especially as regards the screening effect of the K-electrons, the calculated orbital energies are definitely too large. However, the heights found for the cis and the trans barriers are in a reasonable mutual ratio. Numerical values were also obtained for the ionization potentials and the dipole moment of the skew model; the latter result, 2.05 D, agrees well with the experimental data.
THE RAMAN SPECTRUM OF THE SULPHURIC ACIDIUM ION: THE CONSTITUTION OF CONCENTRATED SOLUTIONS OF TETRA(HYDROGENSULPHATO)BORIC ACID IN SULPHURIC ACID
Authors: Gillespie R. J. , Robinson E. A.
Published: May 2006

The Raman spectra of sulphuric acid solutions of tetra(hydrogensulphato)boric acid and its sodium and hydronium salts have been examined. Frequencies are assigned to some of the vibrations of the sulphuric acidium ion, H3SO4+, and are compared with the frequencies of the analogous vibrations of H2SO4 and HSO4−. Evidence is presented that elimination of disulphuric acid occurs between molecules of HB(HSO4)4 to give polymers containing B—O—B linkages.
CONDUCTANCES OF AQUEOUS SOLUTIONS OF SODIUM OCTANOATE AT 25° AND 35° AND THE LIMITING CONDUCTANCE OF THE OCTANOATE ION
Authors: Campbell A. N. , Kartzmark E. M. , Lakshminarayanan G. R.
Published: May 2006

Equivalent conductances, densities, and viscosities of aqueous solutions of sodium octanoate have been determined at 25° and 35 °C, at concentrations ranging from 0.0002 M to 2.8 M. The limiting equivalent conductances of the octanoate ion have been determined as 23.08 mhos and 29.09 mhos, at 25° and 35 °C respectively.Comparison has been made of our experimental conductances with those calculated, using the equations of Robinson–Stokes, of Falkenhagen–Leist, and of Fuoss.No evidence has been found of micelle formation in solutions of sodium octanoate.
THE PROTON MAGNETIC RESONANCE SPECTRA OF CHRYSANTHEMUM ETHYL ESTER AND THE RELATED cis- AND trans-CHRYSANTHEMUMIC ACIDS
Authors: Hutton H. M. , Schaefer T.
Published: May 2006

The high-resolution proton magnetic resonance spectra of a mixture of the cis and trans isomers of chrysanthemum monocarboxylic acid ethyl ester have been studied. The cis-chrysanthemumic and trans-chrysanthemumic acids spectra were obtained to facilitate the interpretation of the complex spectra of the ester. The percentage of the trans isomer in the chrysanthemum ester was measured to be 62.0 ± 1.1%. The cyclopropane proton spin coupling constants were found to be Jcis = 8.7 c.p.s. and Jtrans = 5.4 c.p.s., in reasonable agreement with Karplus' calculations of the dependence of coupling constants on the dihedral angle.
THE NUMBER-AVERAGE AND WEIGHT-AVERAGE MOLECULAR WEIGHT OF SOME NONIONIC SURFACE-ACTIVE AGENTS
Authors: Sirianni A. F. , Cowie J. M. G. , Puddington I. E.
Published: May 2006

Further evidence for the existence of large differences between the weight- and number-average molecular weight for nonionic surface-active substances in nonaqueous solvents has been found when the property is assessed by light-scattering and vapor-pressure-lowering measurements. Equilibrium ultracentrifuge measurements support the results obtained by vapor-pressure-lowering determinations. Sorbitan and glycerol monostearates have been examined in benzene solution.
IONIZATION OF ORGANIC COMPOUNDS: III. BASICITIES OF PROPIONIC ACID AND PROPIONAMIDE
Authors: Edward J. T. , Wang I. C.
Published: May 2006

Protonation constants (pKBH+) of −6.8 and −0.9 have been determined for propionic acid and propionamide, respectively, from measurements of their ultraviolet absorption in various concentrations of sulphuric acid. The ionization ratio of propionamide and of other amides increases more slowly than the Hammett acidity function, h0, with increase in acid concentration. This may be explained by assuming that in a given concentration of sulphuric acid the protonated amide is more heavily hydrated than the protonated Hammett indicator used to establish the h0 scale for this region of acid concentrations.
THE FORMATION AND THE THERMODYNAMIC PROPERTIES OF K2TiCl6 IN KCl-LiCl MELTS
Authors: Mui J. H. , Flengas S. N.
Published: May 2006

The reaction between gaseous titanium tetrachloride and the eutectic melt of potassium and lithium chlorides was investigated at various temperatures and pressures. It was found that, at an optimum temperature of 370 °C, titanium tetrachloride vapor at a pressure of 1 atm reacts with the potassium chloride in the eutectic to yield K2TiCl6 as a solid mixture with lithium chloride.The solubilities of K2TiCl6, and the partial molar properties of the solutions of K2TiCl6, and of potassium chloride, in the eutectic melt of potassium and lithium chlorides were obtained by vapor pressure measurements. It was found that the solubility of titanium tetrachloride increases from 1.5 weight% at 420 °C to 5 weight% at 500 °C. The activities of K2TiCl6, and of potassium chloride, indicate positive deviations from ideality.
THE SULPHURIC ACID SOLVENT SYSTEM: PART III. THE PREPARATION AND STRUCTURES OF SOME COMPLEX SULPHATOBORATES
Authors: Gillespie R. J.
Published: May 2006

By neutralizing sulphuric acid solutions of tetra(hydrogensulphato)boric acid with various metal hydrogensulphates, sodium, potassium, ammonium, and strontium salts have been prepared. From the compositions of these salts, and from the results of cryoscopic and conductimetric measurements on their solutions in sulphuric acid, it is concluded that they are best formulated as polysulphatoborates containing the six-membered ring [Formula: see text]It is shown that previously described sulphato compounds of boron can also be satisfactorily formulated on this basis.
ELECTRON SPIN RESONANCE OF X-RAY-IRRADIATED SINGLE CRYSTALS OF dl-ALANINE HYDROCHLORIDE
Authors: Lin W. C. , McDowell C. A.
Published: May 2006

The electron spin resonance of an X-ray-irradiated single crystal of dl-alanine hydrochloride indicates that the radical formed is probably the same as that produced by X- and γ-ray irradiation of alanine. The components of the hyperfine interaction tensor for the radical have been evaluated.
STUDIES ON THE CHEMICAL BASIS FOR CHOLINOMIMETIC AND CHOLINOLYTIC ACTIVITY: PART I. THE SYNTHESIS AND CONFIGURATION OF QUATERNARY SALTS IN THE 1,3-DIOXOLANE AND OXAZOLINE SERIES
Authors: Triggle D. J. , Belleau B.
Published: May 2006

Structure activity relationships in the muscarine and the quaternary 1,3-dioxolane (Fourneau series) series are briefly discussed. The most active member of the latter series (2-methyl-4-dimethylaminomethyl-1,3-dioxolane methiodide, (IX), F2268) was shown to consist of a mixture of 60% cis and 40% trans isomers. The same was found to apply to all synthetic intermediates in that series. Unequivocal assignments of configuration were made by relating various intermediates leading to (IX) and its analogs to D-cis-1,3-dimethyl-1,3-dioxolane itself, obtained by degradation of 1,6-anhydrogalactose. Attempted separation of cis–trans isomers in the 1,3-dioxolane series was not successful. However, a mixture of cis, trans-2-trichloromethyl-4-hydroxymethyl-1,3-dioxolane (XVI) could be fractionated by crystallization of the corresponding tosylates. Catalytic hydrogenolysis converted the pure cis- and trans-trichloromethyl derivatives (XVII) and (XVIII) to pure cis- and trans-2-methyl-4-hydroxymethyl-1,3-dioxolane tosylates (XIX) and (XX), which eventually afforded for the first time pure cis-F2268 and trans-F2268 (XXII) and (XXIII).Optically active members in the 1,3-dioxolane series were prepared. Members of the D(−)-series were conveniently obtained from D-isopropylidene glycerol. Members of the L(+)-series could be obtained in optically impure forms by resolution of dl-tertiary bases such as (XXXVI) with D- and L-dibenzoyltartaric acid. The best preparations had an optical purity not exceeding 32%. The resolution of the cis base (X) was unsuccessful.The synthesis of an oxazoline analog, (XLIV), of F2268 was accomplished. The reaction sequence involves solvolysis of N-acetyl-2,3-dibromo-n-propylamine (XLI) to give the 5-bromomethyl-2-methyloxazoline (XLII). This unstable intermediate was reacted with dimethylamine to give the tertiary base (XLIII), which was quaternized with methyl iodide whereupon the quaternary base (XLIV) was formed in good yield. The structure of the latter was established by an independent synthesis of the hydrolysis product (XLV).Preliminary pharmacological data are reported for the various new quaternary salts. The compounds were assayed for cholinomimetic activity. It is concluded from these studies that quaternary 1,3-dioxolanes display structure-activity relationships analogous to the muscarones. The use of triethylammonium analogs has revealed a large degree of preference of cholinergic receptors for the presence of a cis configuration in 2,4-disubstituted-1,3-dioxolanes. It was also noted that the oxazoline derivative (XLIV) ranks amongst the most active cholinomimetics thus far reported. Relationships between configuration and activity are briefly discussed.
PHOTOCONDUCTION OF CRYSTALLINE 9,10-DIBROMOANTHRACENE AND 9,10-DICHLOROANTHRACENE
Authors: Smith I.C. , Bock E.
Published: May 2006

not available
THE BINARY (ANHYDROUS) SYSTEMS NaNO3–LiNO3, LiClO3–NaClO3, LiClO3–LiNO3, NaNO3–NaClO3 AND THE QUATERNARY SYSTEM NaNO3–LiNO3–LiClO3–NaClO3
Authors: Campbell A. N. , Kartzmark E. M. , Nagarajan M. K.
Published: May 2006

The equilibrium diagrams of the systems NaNO3–LiNO3, LiClO3–NaClO3, LiClO3–LiNO3, NaNO3–NaClO3, and NaNO3–LiNO3–LiClO3–NaClO3 have been investigated by thermal analysis and, to some extent, by X-ray powder photography. All the binary systems are of the simple eutectic type, accompanied, in one instance, by considerable solid solubility. The allotropic transformation of sodium nitrate complicates the equilibria involving sodium nitrate somewhat, especially when there is solid solution.The quaternary diagram shows that in the (fused) reaction[Formula: see text]lithium nitrate and sodium chlorate constitute the stable solid pair. The two invariant points of this system are both congruent.
A SYNTHESIS OF MIMOSINE
Authors: Spenser Ian D. , Notation Albert D.
Published: May 2006

DL-Mimosine has been sinthesized by debenzylation and detosylation of the product obtained by condensation of 3-benzyloxy-4-pyrone with β-amino-α-tosylaminopropionic acid.A new method for the isolation of mimosine from Leucaena glauca Benth. is described.
SINGLET METHYLENE FROM THERMAL DECOMPOSITION OF DIAZOMETHANE. UNIMOLECULAR REACTIONS OF CHEMICALLY ACTIVATED CYCLOPROPANE AND DIMETHYLCYCLOPROPANE MOLECULES
Authors: Setser D. W. , Rabinovitch B. S.
Published: May 2006

The thermal decomposition of diazomethane (DM) into singlet methylene radicals and nitrogen has been studied from 225° to 450° in 10:1 olefin–diazomethane mixtures. At 2.5 cm pressure, k = 1.2 × 1012 exp (−34,000/RT) sec−1. The methylene radicals have similar reactivity to methylene generated from photolytic decomposition of DM, as judged by the follow-up reactions with ethylene and cis-butene-2. The structural isomerization reactions of energized cyclopropane and the structural and geometric isomerization of 1,2-dimethyl-cyclopropane (DMC), formed from the addition of the thermally generated methylene to the olefins, were measured from 250° to 450° over a wide range of pressures. For comparison, cyclopropane formed from photolysis at 4358 Å and 25° of DM and ethylene was studied. As judged from comparison of the experimental isomerization rate constants, the energy of the cyclopropanes formed at 350° in the thermal DM system is about the same as for cyclopropanes formed by photolysis at 4358 Å of DM at 25°. The experimental rate constants obtained on the assumption of strong collisions are compared with calculated rate constants which are based on quantum statistical models for kE which fit literature data on conventional thermal isomerization of cyclopropane and DMC. From this comparison, the average energies of the formed molecules in the thermal systems are estimated to be between 107 and 115 kcal/mole, depending upon the temperature. Photolysis at 25° of the ketene–ethylene system (3200 Å) and of DM–ethylene system (4358 Å) give cyclopropane characterized as being at 103 and 111 kcal/mole respectively. These energies deduced from kinetic data are compared with available thermochemical quantities; the existing value of ΔHf0(CH2N2) is questioned. Further support for fast intramolecular relaxation of vibrational energy in DMC, relative to the relaxation process for reaction, is noted. Comparison of data in the literature on the ketene and DM photolytic systems strongly suggests that a larger fraction of the excess light energy resides with methylene from ketene (0.65–0.8) than with methylene from DM (0.3–0.5). Various approximations for the calculation of kE are examined and are compared with accurate quantum statistical evaluation.
FREE-RADICAL REACTIONS WITH AROMATIC ETHERS: PART I. BENZOYL PEROXIDE WITH ANISOLE
Authors: Lynch Brian M. , Moore Ralph B.
Published: May 2006

A re-examination of the products of thermal decomposition of benzoyl peroxide in anisole has resolved anomalous findings by previous workers. The expected phenylation of the substrate is accompanied by appreciable benzoyloxylation, and the distribution of isomers in the phenylation and benzoyloxylation products has been examined; the theoretical implications of the results are discussed.
THE POLYMERIZATION OF 1-BUTENE BY TiCl3–Al(i-Bu)3 CATALYSTS
Authors: Jones M. H. , Thorne M. P.
Published: May 2006

An investigation has been made of the polymerization of 1-butene by TiCl3–Al(i-Bu)3 catalysts in heptane solution at 40 °C. The polymerization curve has two segments covering initial and steady-state periods at which the rate increases several fold. The change in rate, which occurs after the formation of a constant amount of polymer for a given concentration of TiCl3, is interpreted as an increase in surface area due to breakdown of the catalyst particles. For the steady-state period, it has been shown that the rate of polymerization is proportional to the monomer and titanium trichloride concentrations and approaches a constant value as the aluminum triisobutyl concentration increases.The intrinsic viscosity of the bulk polymer and the crystallinity, as determined by infrared analysis, were found to be essentially independent of the concentrations of the catalyst components and the extent of polymerization.The results are considered in terms of current theories on the mechanism of heterogeneous polymerization.
DITERPENOID QUINONES OF INULA ROYLEANA D. C.
Authors: Edwards O. E. , Feniak G. , Los M.
Published: May 2006

Three related diterpenoid quinones, royleanone, 9-acetoxyroyleanone, and 9-dehydroroyleanone, have been isolated from the roots of Inula royleana D. C. These have been assigned structures on the basis of degradation studies and the synthesis of royleanone from ferruginol.
STEREOCHEMISTRY OF ARSENIC: PART IV. CHLORODIPHENYLARSINE
Authors: Trotter J.
Published: May 2006

Crystals of chlorodiphenylarsine, (C6H5)2AsCl, are monoclinic with four molecules in a unit cell of dimensions a = 11.09, b = 8.55, c = 11.93 Å, β = 95.0°. The crystals are isomorphous with crystals of the corresponding bromo derivative, and the structure has been determined by the isomorphous replacement method. The mean values of the bond lengths and valency angles (with standard deviations) are: As—Cl = 2.26 ± 0.02 Å, As—C = 1.97 ± 0.04 Å, C—C = 1.39 ± 0.02 Å, [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] The general molecular configuration and the intermolecular separations are very similar to those in bromodiphenylarsine.
THE RANGE OF Cs137 IONS OF KEV ENERGIES IN GERMANIUM
Authors: Davies J. A. , McIntyre J. D. , Sims G.
Published: May 2006

The range of Cs137 ions in germanium has been measured at 4-, 20-, and 40-kev bombardment energy. Two independent methods of determining the depth of penetration were used. The results are in reasonable agreement with our previous range measurements in aluminum, and with the recently published theoretical treatment of Lindhard and Scharff. A possible explanation has been found for the abnormally large value reported by Bredov for the penetration depth of 4-kev Cs134 ions in germanium.
THE X-RAY POWDER DIFFRACTION PATTERNS OF AMMONIA–NICKEL CYANIDE COMPLEXES
Authors: Bhatnagar V. M. , Cloutier J. A. R.
Published: May 2006

not available
A NEW SPRAY FOR THE DETECTION OF HIGHLY SUBSTITUTED ACETALS AND KETALS OF CARBOHYDRATES
Authors: Bird J. W.
Published: May 2006

not available
SYNTHESIS OF CARBON-14 LABELED DEOXYRIBONUCLEOSIDES
Authors: Williams D. L.
Published: May 2006

The enzymatic transfer of deoxyribose from a purine or a pyrimidine deoxyriboside to a carbon-14 labeled purine or pyrimidine base affords an efficient means of preparing labeled deoxyribonucleosides. Deoxyadenosine-8-C14, deoxyguanosine-8-C14, deoxycytidine-2-C14, and thymidine-2-C14, with the natural β-configuration, were prepared in good yields and isolated in radiochemically pure form by large-scale paper chromatography.
THE PROTON RESONANCE SPECTRA AND STRUCTURES OF SUBSTITUTED AZULENES IN TRIFLUOROACETIC ACID
Authors: Danyluk S. S. , Schneider W. G.
Published: May 2006

The proton resonance spectra for a number of substituted azulenes and their conjugate acids are reported at 22 °C. From the spectra for the conjugate acids it is confirmed that monoprotonation occurs in the five-membered ring in each case. The unit electron deficiency is shown to be mainly localized in the seven-membered ring of the ion.Chemical shift changes on protonation are interpreted qualitatively in terms of changes in local π electron charge densities on the carbon atoms.Unusually large values are noted for the coupling constants between protons on the five-membered ring of the cations and are attributed in part to hyperconjugative effects.
THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: I. A GALACTOMANNAN FROM TRICHOPHYTON GRANULOSUM
Authors: Bishop C. T. , Blank F. , Hranisavljevic-Jakovljevic M.
Published: May 2006

A galactomannan containing D-galactose (16%) and D-mannose (84%) has been isolated from the water-soluble polysaccharides of Trichophyton granulosum. Methylation studies showed that the structure was highly branched, the predominant structural feature being a chain of α-D-mannopyranose units joined together by an equal number of 1 → 2 and 1 → 6 linkages. About 22% of the D-mannose units were doubly substituted at positions 2,6; 2,4; and 2,3 to form branch points. The branches were terminated by D-mannopyranose and D-galactofuranose residues, the latter accounting for all of the D-galactose present in the polysaccharide.
THE KINETICS OF THE ALKALINE HYDROLYSES OF DIMETHYL TEREPHTHALATE AND THE TRANS ISOMER OF DIMETHYL 1,4-CYCLOHEXANEDICARBOXYLATE IN DIOXANE–WATER MIXTURES
Authors: Svirbely W. J. , Cunniff Patricia A.
Published: May 2006

The kinetics of the alkaline hydrolyses of dimethyl terephthalate and trans-dimethyl 1,4-cyclohexanedicarboxylate was studied in dioxane–water mixtures varying in dielectric constant from 60 to 11. The effect of the medium on the mechanism and rate constants is, in general, similar to that previously observed in the study of the alkaline hydrolyses of aliphatic diesters.
HIGH-FIELD KINETIC PROCESSES IN ANODIC OXIDE FILMS ON ALUMINUM
Authors: Ryan P. J. , Dignam M. J.
Published: May 2006

not available
SYNTHESIS OF 19-NORTESTOLACTONE
Authors: Bagli Jehan F.
Published: May 2006

not available
3,4-DIHYDRO-β-CARBOLINES: I. THE ALKYLATION OF 1-SUBSTITUTED Nβ-ALKYL-3,4-DIHYDRO-β-CARBOLINE ANHYDRO BASES
Authors: Gupta R. N. , Spenser Ian D.
Published: May 2006

Methylation of the anhydro base derived from 1-methyl-3,4-dihydro-β-carboline methiodide is accompanied by ring opening and yields 3-[2-acetylindolyl]-β-ethyltrimethylammonium iodide, and not a 2,2-dialkyl-1-methylene-1,2,3,4-tetrahydro-β-carbolinium salt, as reported.
STABILIZATION OF POLYMERIC CARBOHYDRATE NITRATES FROM STUDIES ON STARCH, AMYLOSE, AMYLOPECTIN, AND GLYCOGEN
Authors: Mustafa Ahmed , Dawoud Abdel Fattah , El-Shourbani Salah
Published: May 2006

Whole starch, amylose, amylopectin, and glycogen (polymeric carbohydrates of the α-D-glycosidic linkage type) were nitrated by nitric acid in the presence of phosphoric anhydride and stability properties of the nitrated products were studied. Crude amylose nitrate is more stable than amylopectin nitrate and the latter is less stable than the whole-starch nitrate as judged by the Bergmann–Junk test. The stability of glycogen nitrate is closely similar to that of amylopectin nitrate.Appreciable stabilization of the crude nitrates was brought about by boiling with slightly alkaline water for long periods (60–70 hours). All stabilized samples were found to possess closely similar stability properties. The Bergmann–Junk values of all examined nitrates ranged from 2.2 to 1.7 mg of nitrogen per gram sample; the latter value seems to represent the maximum stabilization which could be attained for the polymeric carbohydrate nitrates of the α-D-glycosidic linkage type. In the case of cellulose nitrate (β-D-glycosidic linkage type) Bergmann–Junk values of 1 to 1.25 mg of nitrogen were obtained.
THE CONSTITUTION OF A SYNTHETIC XYLAN: III. METHYLATION STUDIES
Authors: Dutton G. G. S. , Unrau A. M.
Published: May 2006

Hydrolysis of the fully methylated xylan gave a complex mixture of sugars indicating the highly branched nature of the polysaccharide. At least 27% of the internal xylose units were furanose and 38% of the terminal units were also furanose.
ON THE EVALUATION OF CERTAIN TWO- AND THREE-CENTER MOLECULAR INTEGRALS OCCURRING IN ELECTROSTATIC CALCULATIONS
Authors: Bader R. F. W.
Published: May 2006

A general method is developed for the evaluation of the three-center integrals which occur in the application of the Hellmann–Feynman theorem to the study of molecular binding. The method employs Gegenbauer polynomials for the series expansion of the radial dependence of the electric field. It is also shown that the same expansion greatly simplifies the evaluation of the two-center electrostatic penetration integrals. General formulae are presented for these latter integrals for all nonvanishing combinations of s, p, and d atomic orbitals for all principal quantum numbers.
THE PURIFICATION OF SOLVENTS FOR ULTRAVIOLET ABSORPTION SPECTROSCOPY
Authors: Vinogradov Serge N.
Published: May 2006

not available
THE KINETICS OF THE REACTION OF ORGANIC ISOTHIOCYANATES WITH 1-OCTANOL IN o-DICHLOROBENZENE
Authors: Iwakura Yoshio , Okada Hisao
Published: May 2006

The kinetics of the reaction of organic isothiocyanates with a large excess of 1-octanol in o-dichlorobenzene was examined at 90–140°. The rate of the reaction was first order with respect to the concentration of isothiocyanate, but the apparent second-order rate constants calculated varied according to the initial 1-octanol concentration. These facts can be explained by a reaction mechanism involving two molecules of 1-octanol in the transition state for the slow step of the reaction. The relative rate of the reaction of isothiocyanates with 1-octanol at 120° decreased in the order of benzyl, phenyl, allyl, ethyl, n-butyl, n-hexyl, isobutyl, and cyclohexyl isothiocyanate. The apparent energies of activation and log A were obtained as 13.5–16.5 kcal/mole and 4.65–6.46 (A in liter/mole min), respectively. Tributylamine had a slight catalytic effect, but dibutyltin dilaurate and ferric acetylacetonate had a strong catalytic action in these reactions.
THE COMPOSITION OF THE SUCROSE MONOMYRISTATE PREPARED BY TRANSESTERIFICATION
Authors: Lemieux R. U. , McInnes A. G.
Published: May 2006

The composition of the sucrose monomyristate which is obtained by reaction of sucrose with methyl myristate in dimethylformamide and in the presence of a basic catalyst was established by application of gas–liquid partition chromatography and nuclear magnetic resonance spectroscopy to appropriate derivatives. The substance is a mixture of 6′-myristoyl sucrose, 6-myristoyl sucrose, and unidentified isomeric esters in the relative proportions of 0.62:0.28:0.10, respectively.
REACTIONS OF THE DIMER OF 2,4-TOLYLENE DIISOCYANATE
Authors: Singh Pritam , Boivin Jean L.
Published: May 2006

not available
NEW APPROACHES TO THE STUDY OF ELECTROCHEMICAL DECARBOXYLATION AND THE KOLBE REACTION: PART III. QUANTITATIVE ANALYSIS OF DECAY AND DISCHARGE TRANSIENTS AND THE ROLE OF ADSORBED INTERMEDIATES
Authors: Conway B. E. , Dzieciuch M.
Published: May 2006

Galvanostatic cathodic discharge and open-circuit decay transients have been obtained for the decarboxylation of formate in formic acid and interpreted quantitatively in terms of the adsorption of intermediates in the reaction. These intermediates are identified with HCOO• radicals. Extended anodic polarization at platinum and particularly at palladium leads to the formation of films of an anodic product which are considerably thicker than a monolayer. After relatively long times (> 100 seconds) of anodic polarization, the film growth obeys the inverse logarithmic rate law deduced by Mott and Cabrera. The thick films which are formed at palladium are believed to be responsible, upon autocatalytic decomposition, for the delayed gas evolution phenomenon observed at this metal.A new method for deduction of adsorption pseudocapacitance and charge associated with the ad-layer from open-circuit decay curves and Tafel parameters is used to obtain the pseudo-capacitance and charge associated with the transition region in the current–potential curves for the formate decarboxylation. It is shown that this region corresponds to filling of the surface with adsorbed intermediates formed in the reaction. These observations are shown to support the reaction mechanism proposed in Part I.
LIQUID-LIQUID EXTRACTION OF BERYLLIUM: II. STUDIES OF BERYLLIUM–THIOCYANATE EXTRACTION
Authors: Biermann Wendell J. , McCorkell Robert
Published: May 2006

The partition of beryllium and aluminum between aqueous thiocyanate solutions and several organic solvents was determined under a variety of experimental conditions. From these batch studies it was concluded that a two-solvent countercurrent extraction of beryllium from a thiocyanate solution should give good recovery of beryllium with effective separation from aluminum and, by inference, other inert gas configuration cations.
THE ORIGIN OF CARBON ATOMS 2, 3, AND 7 OF RICININE
Authors: Juby P. F. , Marion Léo
Published: May 2006

The isolation of carbon atoms 2 and 3 of the α-pyridone nucleus of ricinine is described. Evidence is provided to support the suggestion that succinic acid or a closely related four-carbon dicarboxylic acid provides carbon atoms 2, 3, and 7 in the biosynthesis of the ricinine molecule.
A NUCLEAR MAGNETIC RESONANCE INVESTIGATION OF THE PROTONATION OF AMIDES IN FLUOROSULPHURIC ACID
Authors: Gillespie R. J. , Birchall T.
Published: May 2006

The proton resonance spectra of solutions of acetamide, N,N-dimethylacetamide, formamide, and N,N-dimethylformamide in fluorosulphuric acid have been studied at temperatures between 25° and −98°. At low temperatures a new peak appears in the spectra of solutions of all four compounds which is not present at room temperatures and which, from peak areas and other consideration, may be assigned with certainty to the [Formula: see text] group. It is thereby unambiguously established that these amides protonate on the carbonyl oxygen and not on the nitrogen atom.
CHARACTERISTIC VIBRATIONAL FREQUENCIES OF OXYGEN COMPOUNDS OF PHOSPHORUS AND CHLORINE: CORRELATION OF SYMMETRIC AND ASYMMETRIC STRETCHING FREQUENCIES OF PO AND ClO BONDS
Authors: Robinson E. A.
Published: May 2006

Linear relationships have been established between the symmetric and asymmetric stretching frequencies of PO2 and ClO2 groups that are useful in the assignment of the characteristic vibrational frequencies of these groups in the Raman and infrared spectra of phosphorus and chlorine compounds containing two or more oxygen ligands. The values of the frequencies depend, in a systematic manner, on the electronegativities of the groups attached to the central atom.
STEREOCHEMISTRY OF ARSENIC: PART VII. IODODIPHENYLARSINE
Authors: Trotte J.
Published: May 2006

not available
HYDROGEN BONDING IN HALOFORM SOLUTIONS
Authors: Paterson W. G. , Cameron D. M.
Published: May 2006

not available
KINETICS AND MECHANISM OF THE PERSULPHATE OXIDATION OF 2-PROPANOL AND 2-BUTANOL
Authors: Levitt L. S. , Levitt Barbara W.
Published: May 2006

not available
X-RAY DIFFRACTION DATA FOR ALKALI DITHIONATES
Authors: Larson D. W. , VanCleave A. B.
Published: May 2006

X-Ray powder diffraction patterns have been recorded for the alkali dithionates and for barium and ammonium dithionate. The patterns have been indexed and unit cell dimensions determined for lithium dithionate dihydrate, sodium dithionate (anhydrous), and rubidium dithionate. Previously determined cell dimensions have been confirmed in other cases.
DIELECTRIC EVIDENCE FOR ACETONE HYDRATE
Authors: Wilson G. J. , Davidson D. W.
Published: May 2006

The phase diagram of the acetone–water system shows that acetone hydrate decomposes at an incongruent melting point. The existence of acetone hydrate is confirmed by a study of the low-frequency dielectric properties of this system. A dispersion region, related to the relaxation of water molecules in the clathrate structure, is characterized by a "static" dielectric constant and an activation energy about half as large as the corresponding values for ice, and by a limiting high-frequency dielectric constant of about 7 at 200° K. The magnitude of the latter is attributed to orientation of acetone molecules within the larger cavities of the hydrate structure.
REACTIONS OF PHENYL-SUBSTITUTED HETEROCYCLIC COMPOUNDS: I. NITRATION OF 2-PHENYL-1,2,3,2H-TRIAZOLE
Authors: Lynch Brian M. , Chan Tze-Lock
Published: May 2006

Structures have been assigned to the mono-, di-, and tri-nitration products of 2-phenyl-1,2,3,2H-triazole, on the basis, partly, of ultraviolet absorption spectra. The pattern of nitration closely resembles that of 1-phenylpyrazole. A compound previously described as 2-(o-nitrophenyl)-1,2,3,2H-triazole is actually 4-nitro-2-p-nitrophenyl-1,2,3,2H-triazole.
THE MERCURY-PHOTOSENSITIZED DECOMPOSITION OF PROPANE: A MASS SPECTROMETRIC STUDY AT LOW PRESSURES: PART I
Authors: Kebarle P. , Avrahami M.
Published: May 2006

It is found that the primary decomposition involves the cleavage of a C—H bond. Both primary and secondary hydrogen atoms are lost. The relative rates of the two processes could not be determined accurately but are estimated to be approximately 1:1. It is found that at least 70% of the secondary reactions involves the interaction of hydrogen atom with a propyl radical. The main reaction is the re-formation of propane. An important disproportionation of hydrogen atoms with propyl radicals leading to propylene is shown to occur. The atomic cracking reaction H + C3H7 → C3H8* → C2H5 + CH3 is also observed. Using mixtures of C3H8 and C3D8 the relative cracking rate of n-propyl- to isopropyl-derived propane is determined to be equal to 5. This result is compared with theoretical predictions.
THE BEHAVIOR OF D-GLUCURONIC, D-GALACTURONIC, AND D-MANNURONIC ACID IN DILUTE AQUEOUS SODIUM HYDROXIDE
Authors: Siddiqui I. R. , Purves C. B.
Published: May 2006

Two percent aqueous sodium hydroxide at room temperature, preferably for 24 hours, was used to obtain the Lobry de Bruyn – van Ekenstein transformation products. The transformations proceeded much more slowly than in the case of the hexoses; complex changes in specific rotation occurred, and equilibrium among the products was not attained, probably because acidic non-reducing substances formed at a comparable rate. After 24 hours, 39% of D-glucurone was recovered unchanged, together with 9% of D-mannuronic acid and 2% of keto acid probably based on fructose. D-Mannurone gave the same products, but unchanged starting material once more predominated. D-Galacturonic acid was recovered in 58% yield together with 12% of D-taluronic acid, a new substance characterized as a crystalline mono-hydrated brucine salt. A trace of a keto acid, presumably derived from D-tagatose, was also formed.
SOLVENT SHIFT OF THE CHLOROFORM NUCLEAR MAGNETIC RESONANCE LINE
Authors: Kaiser Reinhold
Published: May 2006

The chloroform and dioxane proton magnetic resonance line positions have been measured relative to an internal tetramethylsilane reference signal as a function of concentration in binary chloroform −1,4-dioxane mixtures at 28 °C. Corrections have been applied to eliminate the effects of the chloroform self-association and of the non-specific interactions of the chloroform dipole. Analysis of the remaining nuclear magnetic resonance line shift in terms of an equilibrium between free chloroform and 1:1 and 2:1 chloroform-dioxane complexes gives the position of the signal from chloroform in the 1:1 complex at −1.20 p.p.m. and in the 2:1 complex at −0.85 p.p.m. relative to the position of the signal from chloroform at infinite dilution in cyclohexane. Data on other binary chloroform systems have been collected from the literature and have been similarly corrected. The results support the hypothesis of a monotonic relation between the proton magnetic resonance line shift and the energy of the hydrogen bonds which are believed to cause the formation of complexes in these systems. The accuracy of the data is not sufficient to give conclusive evidence regarding the linearity of this relation or the structure of the 2:1 chloroform–dioxane complex.
GALVANIC STRESS POTENTIALS OF METALS
Authors: Tan S. , Nobe Ken
Published: May 2006

The electrode potential of silver, brass, and steel wires under tensile stress have been measured in aqueous solutions of silver nitrate, copper sulphate, and ferrous sulphate, respectively. The stress potentials were continuously measured with a stabilized d-c. microvolt amplifier which made possible the study of the transient and the steady-state period during loading and unloading. The stressed silver and steel electrodes were cathodic with respect to the reference electrode, and the e.m.f. was approximately a linear function of the stress. The slope of the e.m.f.–stress curve for silver increased with decrease in electrolyte concentration. The stressed brass electrode was anodic with respect to the reference electrode and the e.m.f. varied linearly with stress only for 1 N CuSO4.
PROTONATED γ-PYRONES
Authors: Cook Denys
Published: May 2006

The vibrational spectra of several salts of 4-pyrone and 2,6-dimethyl-4-pyrone have been measured in the solid state. Deuterium replacement has been used to identify motions of the hydrogen atom which is located on the carbonyl oxygen atom and forms a hydrogen bond with the anion.Bands due to OH stretching vibrations have been observed from 2086 cm−1 in the HCl salt to 3310 cm−1 in the hexachloroantimonate of 2,6-dimethyl-4-pyrone. In-plane hydrogen-deformation modes of the OH group have been found near 1300 cm−1 with a much smaller range in the different salts than the stretching vibration. For the 4-pyrone salts the OH stretching vibrations were at similar frequencies, and the in-plane hydrogen-deformation frequencies were close to 1340 cm−1. Bands due to the out-of-plane deformation were not observed.Aqueous solutions of 2,6-dimethyl-4-pyrone hydrochloride at various concentrations showed the presence of both protonated and neutral molecules.
INFRARED SPECTRA OF COMPLEXES OF 4-PYRIDONES
Authors: Cook Denys
Published: May 2006

The infrared spectra of many complexes of Lewis acids with some 4-pyridones have been recorded. Large shifts to lower frequencies of about 100 cm−1 have been observed in a band near 1560 cm−1 as the Lewis acid strength increased. Much smaller shifts of about 5 to 10 cm−1 in a band near 1640 cm−1 were noted. The former band has therefore been designated as the carbonyl frequency, and the latter as a ring mode involving CC stretching.The donor site of 4-pyridones is therefore the carbonyl group, and not the nitrogen atom. Protonated 4-pyridones have similar spectra, and are consistent with O-, not N-protonation.
PHASE EQUILIBRIUM STUDIES FOR THE QUATERNARY SYSTEM URANYL NITRATE – ALUMINUM NITRATE – NITRIC ACID – WATER
Authors: Thibodeau Robert D. , Adelman M.
Published: May 2006

The quaternary system UO2(NO3)2−Al(NO3)3−HNO3−H2O) was studied in the temperature range 0–20 °C, and the concentration range of 0–1.5 M Al(NO3)3 and 0–10 N HNO3. From the data, phase diagrams were prepared. No phase separation was evident at 30 °C and above, for the concentrations studied.
AZA STEROIDS: II. SYNTHESIS OF 6-AZA STEROIDS—A NOVEL CLASS OF AZAANDROSTANE ANALOGUES
Authors: Kutney James P. , Johnson Roy A. , Vlattas I.
Published: May 2006

A synthesis of N-benzyl-6-azacholestane is described and the generality of the approach is exemplified by the successful synthesis of 17β-hydroxy-N-benzyl-6-azaandrostane. This represents the first synthesis of a 6-aza derivative in the androstane series.
AN INVESTIGATION OF THE ALUMINUM–OXYGEN–CARBON SYSTEM
Authors: Cox J. H. , Pidgeon L. M.
Published: May 2006

A differential thermal analysis technique was used to study the carbothermic reduction of aluminum oxide at reduced pressures in the temperature range 1700–2200 °K. The reduction was found to proceed through the intermediate oxycarbide Al4O4C, identified by previous workers, to the aluminum carbide. The Al4O4C and another oxycarbide, Al2OC, were formed by a direct solid–solid reaction, rather than by formation of a gaseous aluminum suboxide and subsequent reaction with carbon as has been postulated.The carbon monoxide pressures over the following reactions were measured:[Formula: see text]Heats and free energies of reaction were found and standard heats and free energies of formation were calculated for Al2OC, Al4O4C, and Al4C3. The values for Al4C3 agreed with previously published results.The direct reaction[Formula: see text]did not occur. To account for the aluminum produced at high temperatures, the reaction below was postulated:[Formula: see text]The calculated equilibrium pressure above this reaction agreed with experimental observations.
PYRAZOLINES: PART III. THE PREPARATION AND PYROLYSIS OF 4,5-DIMETHYL-3-CARBOMETHOXY-Δ2-PYRAZOLINE AND 3,5-DIMETHYL-3-CARBOMETHOXY-Δ1-PYRAZOLINE
Authors: McGreer Donald E. , Morris Peter , Carmichael George
Published: May 2006

4,5-Dimethyl-3-carbomethoxy-Δ2-pyrazoline and 3,5-dimethyl-3-carbomethoxy-Δ1-pyrazoline have been synthesized and pyrolized neat and in the vapor phase. The product analysis from these and a related dimethyl-3-carbomethoxypyrazoline indicate that substituent effects of methyls in the ring are cumulative.
PROTON MAGNETIC RESONANCE SPECTROSCOPY AND THE SULPHATION OF LINEAR AND BRANCHED DEXTRAN
Authors: Pasika W. M. , Cragg L. H.
Published: May 2006

The introduction of sulphate groups into dextran produces characteristic changes in its proton magnetic resonance spectrum. With linear dextran a new signal appears which can be attributed solely to an effect of sulphate groups; with branched dextran this signal coincides with that due to the branching. From a comparison of peak areas in these spectra with peak areas in the spectra of the unsulphated linear and branched dextrans it is concluded that during sulphation no appreciable degradation occurred, whether by chain scission or branch hydrolysis.The proton magnetic resonance spectra also provide evidence for preferential substitution of sulphate at carbon 2 in the anhydroglucose unit.
THE CONFIGURATION OF DEOXYSTREPTAMINE
Authors: Lemieux R. U. , Cushley R. J.
Published: May 2006

The nuclear magnetic resonance (n.m.r.) spectrum of 5-O-methyl-l,3-di-N-methyl-4,6-di-O-acetyldeoxystreptamine dihydrogenperchlorate requires the all-trans configuration since the signal for the equivalent ring hydrogens at the 4- and 6-positions is in the form of a triplet with a spacing of 10 c.p.s. This spacing requires these hydrogens to be axial and coupled with axial hydrogens at the neighboring 1-, 3-, and 5-positions.
THE STRUCTURE OF STRYCHNOSPERMINE EVIDENCE FROM DOUBLE IRRADIATION AND VARIABLE TEMPERATURE N.M.R.
Authors: Anet F. A. L.
Published: May 2006

The nuclear magnetic resonance spectrum of strychnospermine has been measured at −20°, room temperature, and at +80°. The changes observed are attributed to restricted rotation in the N-acetyl group. At room temperature the rate of rotation is such that the band of one aromatic proton is extremely broad and therefore almost invisible. Double irradiation has been used to determine the environment of the C-methyl group of the alkaloid. The n.m.r. results confirm the structure previously postulated.
THE NUCLEAR MAGNETIC RESONANCE SPECTRUM OF SULPHUR TETRAFLUORIDE
Authors: Bacon J. , Gillespie R. J. , Quail J. W.
Published: May 2006

not available
AZOESTER-ANTHRACENE REACTIONS
Authors: Huffman C. W.
Published: May 2006

not available