bluuebunny/crossref_metadata_2025 huggingface dataset:
SYNTHESIS IN THE FIELD OF THE ERYTHRINA ALKALOIDS: PART I. THE SYNTHESIS OF HEXAHYDROAPOERYSOTRINE
Authors: Belleau B.
Published: May 2006

The synthesis of the complete ring system of the aromatic class of Erythrina alkaloids is described. The basic sequence involves reaction of hexahydroindole (whose preparation was studied in some detail) with phenylacetyl chloride to give the ketoamide (VII) which suffered ring closure to the desired ring system (XI) when treated with polyphosphoric acid. Reduction of XI with lithium aluminum hydride gave the corresponding base (XIII). Evidence in support of structure XI is presented. Application of the same sequence with homoveratroyl chloride as starting material led ultimately to the spiroamine (XIV) which proved identical with a sample of natural origin. The stereochemistry of the spiroamines is discussed and the reaction mechanisms involved are critically examined. The new cyclization reaction was successfully applied to the system phenylacetamide–cyclohexanone in an effort to explore its scope.
THE LOCATION AND DISTRIBUTION OF SUBSTITUENTS IN A PURIFIED HYDROXYETHYL CELLULOSE
Authors: Brownell H. H. , Purves C. B.
Published: May 2006

A purified hydroxyethylcellulose of molar substitution 1.33 was completely hydrolyzed in acid, and paper chromatography of the neutral hydrolyzate separated glucose, the three possible hydroxyethyl glucoses, the three di(hydroxyethyl) derivatives, and 2,3,6-tri-O-hydroxyethyl glucose. These substances were isolated as sirups possibly contaminated with the corresponding hydroxyethoxyethyl and higher homologues, which had nearly the same Rf values in the system used. The chromatographic behavior of each of the seven hydroxyethyl glucoses was established by synthetical methods from methyl 4,6-O-benzylidene glucoside, 1,2;5,6-di-O-isopropylidene, and 1,2;3,5-di-O-methylene glucofuranose. Methyl 2,3-di-O-hydroxyethyl-4,6-O-benzylidene-β-glucopyranoside, m.p. 98°–100° and 119–121°, and 1,2-mono-O-methylene glucofuranose, m.p. 147°, were new substances.A quantitative examination of the hydrolyzates showed that the condensation between alkali cellulose and ethylene oxide was nearly homogeneous, that the primary hydroxyl groups in the anhydroglucose units reacted fastest, and those in the third positions slowest. The average substituent had a polyoxyethylene chain length of 1.6 units. Three commercial hydroxyethylcelluloses of apparent M.S. about 1.4 contained non-carbohydrate polyethylene glycols.
THE KINETICS OF ADSORPTION OF n-HEPTANE ON CARBON BLACK AT LOW PRESSURES
Authors: Dacey J. R. , Young D. M. , Mcdougall H. J.
Published: May 2006

The rates of adsorption at constant pressure of n-heptane on 'Spheron 6' carbon black have been measured between 0° and 30 °C. in the pressure range 0.005–0.120 mm., using a sensitive quartz spiral technique. From the results the diffusion coefficient has been calculated both as a function of temperature and as a function of surface concentration, and the activation energy for diffusion calculated as a function of surface concentration. The heat of adsorption, calculated as a function of surface concentration from isotherms measured under the above conditions, is the same as the activation energy. Accordingly, a model is proposed in which the heptane molecules diffuse into the powder mass by a series of jumps across the interparticle space. The distribution of heptane within the carbon bed at various times during adsorption has been calculated.
A STUDY OF SULPHATE IN NITROCELLULOSE USING S35O4− AS TRACER
Authors: Bricknell A. G. , Trevoy L. W. , Spinks J. W. T.
Published: May 2006

S35O4− has been used to show that the residual sulphur in nitrocellulose is not held by adsorption on the surface, as sulphate. Evidence has been obtained to support the view that the sulphur which is not removed by washing after nitration and subsequent stabilization is present within the fibrous structure.
SYNTHESIS OF PORPHOBILINOGEN
Authors: Jackson A. H. , MacDonald S. F.
Published: May 2006

The pyrrole Ib has been converted by several routes into 5-carboxy-porphobilinogen (IIe), the lactam of which is easily decarboxylated to porphobilinogen lactam (IVc). Hydrolysis of the latter gives porphobilinogen (V).
THE PHOTOINITIATED ADDITION OF MERCAPTANS TO OLEFINS: III. THE KINETICS OF THE ADDITION OF THIOPHENOL TO STYRENE AND TO 1-OCTENE
Authors: Pallen R. H. , Sivertz C.
Published: May 2006

Kinetic studies were made of the free radical photoinitiated addition of thiophenol to 1-octene and to styrene in the absence of oxygen. In addition to the usual attack, chain transfer, and termination steps, it is found that a reverse reaction accompanies the attack step, [Formula: see text] The rate constants for the thiophenol–styrene reaction were calculated to be [Formula: see text]kt = 2 × 107 liters.moles−1sec.−1. The over-all activation energies for the two reactions were found to be E (1-octene) = 1.2 kcal., E (styrene) = 2.4 kcal.; suggestions are submitted as to why these activation energies are so low. These reactions are compared with n-butyl mercaptan – olefin reactions.
A DILUTION VISCOMETER FOR FOAMING LIQUIDS
Authors: Nawab M. A. , Goring D. A. I. , Mason S. G.
Published: May 2006

not available
THE HYSTERESIS LOOP IN ADSORPTION ISOTHERMS ON POROUS VYCOR GLASS AND ASSOCIATED DIMENSIONAL CHANGES OF THE ADSORBENT. II
Authors: Quinn H. W. , McIntosh R.
Published: May 2006

The causes of hysteresis in the adsorption isotherms on porous Vycor glass are discussed, employing as ancillary evidence the dimensional changes of the adsorbent. Diagrams of domain complexions for pores of the ink-bottle type are given and used to develop certain of Everett's theorems. Evidence showing the interdependence of domains or voids is given. The compressibility of the porous adsorbent is evaluated and shown to differ with different adsorbates, which suggests distributions of adsorbed matter specific to the adsorbate. A thermodynamic development is given, which indicates that the most stable states of the system are represented along the adsorption isotherm. Finally, certain anomalous findings in the region of low adsorption and within the hysteresis loop are reported and discussed.
HYDRIDE TRANSFER TO CARBONIUM IONS: I. THE MECHANISM OF THE REDUCTION OF TRIPHENYLMETHYL CARBONIUM ION IN FORMIC ACID
Authors: Stewart Ross
Published: May 2006

In an attempt to prove that reduction can take place by hydride transfer, the conversion of triphenyl carbinol in formic acid to triphenylmethane via the carbonium ion was examined. Kinetic and isotopic proof was obtained for the following mechanism:[Formula: see text][Formula: see text]The rate law based on the above mechanism is[Formula: see text]where R = C6H5, which leads to the integrated rate expression[Formula: see text]This equation was found to be obeyed under a variety of conditions.Anhydrous formic-d acid was synthesized in good yield by the glycerol catalyzed decomposition of oxalic acid-d2. The concentration of deuterium was shown by nuclear magnetic resonance spectroscopy to be greater than 99%. Use of this material in the reduction gave a kinetic isotope effect and led to isolation of triphenylmethane which had greater than 97% deuterium in the α-position, thus supporting the idea that a hydride ion was transferred from formate ion to the carbonium ion.The energy and entropy of activation for the rate controlling step have been found to be 18.3 kcal. per mole and −7.5 e.u. The negative ΔS‡ is presumably due to the less likely orientation for the transition state A as compared to B.[Formula: see text]
FREE RADICALS BY MASS SPECTROMETRY: XIII. THE MERCURY PHOTOSENSITIZED DECOMPOSITION OF ALLENE AND BUTADIENE: THE C3H3 RADICAL
Authors: Collin J. , Lossing F. P.
Published: May 2006

The Hg(3P1) photosensitized decomposition of allene leads to the formation of a C3H3 radical. The reaction of this radical with added methyl radicals shows it to have the propargyl (ĊH2—C≡CH) structure rather than the alternative allenyl (CH2=C=ĊH) structure. The dissociation of 1,2-butadiene proceeds by two modes, one to give H2 + C4H4, and the other a split into CH3 and C3H3 radicals. The dissociation of 1,3-butadiene leads to the same final products, a shift of a hydrogen atom being required for the split into free radicals. No evidence was found for a dissociation of 1,3-butadiene into two vinyl radicals. Considerable polymer formation occurred with all three compounds.
THE FRACTIONATION OF POLYSACCHARIDES BY THE METHOD OF ULTRAFILTRATION
Authors: Wilkie K. C. B. , Jones J. K. N. , Excell Barbara J. , Semple R. E.
Published: May 2006

Ultrafiltration of an aqueous solution of a synthetic mixture of inulin and clinical dextran has been used to separate the two polysaccharides. A clinical dextran has also been fractionated in the same way to yield five dextran fractions having number-average molecular weights ranging from 11,000 for the lowest to 190,000 for the highest fraction.
THE STRUCTURE OF ALUMINUM DI- AND TRI-SOAPS
Authors: Leger A. E. , Haines R. L. , Hubley C. E. , Hyde J. C. , Sheffer H.
Published: May 2006

Confirmation of the existence of aluminum trilaurate has been obtained by using infrared absorption to follow the course of the reactions of trimethylaluminum and aluminum isopropoxide with lauric acid. The trisoap is shown to exist as micelles of high molecular weight in solution, the size decreasing on dilution or elevation of temperature. On hydrolysis to the disoap, hydrogen bonding does not appear to play a significant role in the formation of polymer structures. Coordination of carboxylate groups with aluminum is shown to be a major feature of the structure of both tri- and di-soaps. Spectral assignments in the 6.0 to 6.4 μ region have been made for various types of inter- and intra-molecular coordination. The effects of dilution, hydrolysis, and hydrochlorination of aluminum trilaurate in solution have been assessed by viscosity, light-scattering, and infrared measurements.
THE REACTION OF NITROUS ACID WITH 4-SUBSTITUTED-THIOSEMICARBAZIDES
Authors: Lieber Eugene , Pillai C. N. , Hites Ralph D.
Published: May 2006

The reaction of nitrous acid with 4-alkyl- or 4-aryl-thiosemicarbazides, as well as the reaction of alkyl- or aryl-isothiocyanates with hydrazoic acid, leads to the identical 5-(substituted)amino-1,2,3,4-thiatriazole. This has been established by infrared absorption and chemical degradation studies. The reaction of the 5-(substituted)amino-1,2,3,4-thiatriazoles with aqueous bases leads to two competitive reactions: (1) degradation to an isothiocyanate and azide ion, and (2) isomerization to a 1-substituted-tetrazole-5-thiol, the extent of path (1) or (2) depending on the nature of the substituent. Path (1) predominates when the substituent is alkyl, whereas when the substituent is aryl both paths (1) and (2) occur, the relative proportion depending on the electrical nature of the aromatic group, path (2) increasing as the electronegativity increases. The 1-aryl-tetrazole-5-thiols were found to be thermally unstable at their melting points, degrading more or less violently to one mole proportion of pure nitrogen with the formation of sulphur and organic products of lower melting point as yet unidentified. Theories to account for these observations are presented and discussed.
Bis-ORGANOMAGNESIUM REACTIONS: I. EFFECT OF SOLVATION ON ENOLIZATION
Authors: Guthrie C. A. , Spencer E. Y. , Wright George F
Published: May 2006

The reaction of bis-organomagnesium compounds with benzoin has been used to determine the effect of co-ordinative solvents on these halogen-free organometallic compounds after the test reaction has been re-examined to establish its reliability. Although the reaction of ether-free dimethylmagnesium is sufficiently different from reactions in which ethers of varying basicity are present to show that co-ordination is significant, this co-ordination seems to be relatively unimportant by contrast to organometallic systems containing halogen.
THE INFRARED AND RAMAN SPECTRA OF TOLUENE, TOLUENE-α-d3, m-XYLENE, AND m-XYLENE-αα′-d6
Authors: Wilmshurst J. K. , Bernstein H. J.
Published: May 2006

The infrared spectra of toluene, toluene-α-d3, m-xylene, and m-xylene-αα′-d6 have been obtained from 2 to 30 μ for the vapors and liquids. The Raman spectra of the liquids have also been obtained photoelectrically together with depolarization ratios. Vibrational assignments have been made for the four molecules consistent with vapor band contours, polarization data, the Teller Redlich ratio rule, and a modified ratio rule due to Fitzer and Scott.
A NOTE ON THE HYDROCARBON DIBENZO(cd, mn)PYRENE
Authors: Lister M. W.
Published: May 2006

not available
SEPARATION, MOLECULAR WEIGHT, AND INTERACTIONS OF HORSE GLOBIN COMPONENTS
Authors: Haug Arne , Smith David B.
Published: May 2006

Horse globin had been shown previously to dissociate into four subunits by suitable adjustment of pH and ionic strength. Two components have been separated electrophoretically. One of these separated components associates readily as pH and ionic strength are varied. The second component shows little tendency to associate with itself. The behavior of unfractionated globin indicates that interactions occur between these two components.
CONDUCTIVITY OF AQUEOUS SOLUTIONS OF SOME PARAFFIN CHAIN SALTS
Authors: Goddard E. D. , Benson G. C.
Published: May 2006

Specific conductivities of aqueous solutions of sodium dodecyl sulphate, sodium decyl sulphate, and sodium octyl sulphate were measured over concentration ranges about the respective CMCs and at temperatures from 10° to 55 °C. Values of the increase in heat content associated with micelle formation are estimated from the temperature variation of the CMC and the relation of these results to the theory of micelle formation is considered.
SELECTIVE SUBSTITUTION IN SUCROSE: II. THE SYNTHESIS OF 2,3,3′,4,4′-PENTA-O-METHYL SUCROSE AND C4 TO C6 ACETYL MIGRATION IN SUCROSE
Authors: McKeown G. G. , Hayward L. D.
Published: May 2006

Deacetylation of crystalline tri-O-trityl-penta-O-acetyl sucrose gave an amorphous tri-O-trityl sucrose derivative and methylation of this product followed by graded hydrolysis with acetic acid yielded a sirupy penta-O-methyl sucrose. Hydrolytic cleavage of the penta-O-methyl sucrose to nearly equal amounts of 2,3,4-tri-O-methyl-D-glucose and 3,4-di-O-methyl-D-fructose established the original positions of the O-trityl groups at the primary carbons in the sucrose molecule. It was therefore evident that acetyl migration from C4 to C6 in the glucose moiety had occurred during an earlier synthesis of 1′,4,6′-tri-O-methyl sucrose from the tri-O-trityl-penta-O-acetyl sucrose. The probable conformation of the transition state in the acyl migration is discussed.
THE ANALYSIS OF NUCLEAR MAGNETIC RESONANCE SPECTRA: II. TWO PAIRS OF TWO EQUIVALENT NUCLEI
Authors: Pople J. A. , Schneider W. G. , Bernstein H. J.
Published: May 2006

This paper deals with the analysis of the nuclear magnetic resonance spectrum of two pairs of two equivalent nuclei (of spin [Formula: see text])whose relative chemical shift is of the same order as the spin-coupling constants of the system (A2B2 in the notation of Part I). The complete matrix is set up and correlated with the results of McConnell, McLean, and Reilly (4) for the corresponding theory with large chemical shiftsThe proton resonance spectrum of naphthalene is reported and is analyzed as an A2B2 system on the hypothesis that spin couplings between protons on different rings are negligible. A complete analysis of the spectrum of o-dichlorobenzene, which represents a further example of an A2B2, system, is also given. The spectrum of 1-chloro-2-bromoethane at room temperature is also analyzed as an A2B2 system.
THE CONFIGURATION OF GLYCOSIDIC LINKAGES IN OLIGOSACCHARIDES: V. THE SUCROSE LINKAGE IN RAFFINOSE AND STACHYOSE
Authors: Mitra A. K. , Perlin A. S.
Published: May 2006

A direct chemical proof is provided for the occurrence of the sucrose linkage in raffinose and stachyose by isolation of sucrose, after selective removal of D-galactose units. The procedure used takes advantage of the fact that the D-galactopyranosyl residues contain a cis-α-glycol group which, in contrast to the trans glycol group of the other sugar residues, is rapidly attacked by ethanolic periodate. The resulting dialdehyde is alkali-labile and preferentially hydrolyzed with dilute base, the alkali-stable sucrose unit being released intact.
VAPOR ABSORPTION SPECTRA AND OSCILLATOR STRENGTHS OF NAPHTHALENE, ANTHRACENE, AND PYRENE
Authors: Ferguson J. , Reeves L. W. , Schneider W. G.
Published: May 2006

Vapor absorption spectra have been measured for naphthalene, anthracene, and pyrene using a modified Beckman DU Spectrometer. Vapor concentrations were determined using published vapor pressure data, and oscillator strengths were computed for a total of five transitions in the three molecules. It was found that the vapor oscillator strengths are considerably lower than in solution by a factor greater than that predicted by classical theory. An absorption region at about 41,000 cm.−1 in anthracene is tentatively assigned as the 1B2u+ state calculated by Pariser to lie at 42,400 cm.−1.
VOLTAIC CELLS IN FUSED SALTS: PART I. THE SILVER – SILVER CHLORIDE, COBALT – COBALTOUS CHLORIDE SYSTEM
Authors: Flengas S. N. , Ingraham T. R.
Published: May 2006

A reversible silver − silver chloride reference electrode for use in melts at high temperatures has been developed. It was found that the solution of silver chloride in an equimolar mixture of KCl–NaCl melt is ideal for the range of concentrations studied, i.e. 1.0 × 10−3 to 6.0 × 10−2 mole fraction of AgCl.The electromotive force of the voltaic cell[Formula: see text]in which the half-cell to the right contains the above-mentioned reference electrode, was measured as a function of CoCl2 concentration. The applicability of the Nernst equation to this system was established. Deviation from ideality was observed in the case of the solution of CoCl2 in the melt solvent, and this was attributed to the formation of a complex. The dissociation constant of this complex was calculated as 4.50 × 10−2 at 710 °C.The effect of temperature on the electromotive force of this cell was also measured, and the heat of the cell reaction in the presence of solvent (Co + 2AgCl → CoCl2 + 2Ag) was calculated from the data as 22.8 ± 1.3 kcal.The thermodynamic significance of the standard electrode potential of the Co–Ag voltaic cell, derived experimentally as 0.324 volt, is discussed briefly.
ATTEMPTED LOCATION OF THE SUBSTITUENT IN CELLULOSE XANTHATE BY NEW METHODS
Authors: Sanyal Amiya K. , Falconer E. L. , Vincent D. L. , Purves C. B.
Published: May 2006

Cellulose sodium xanthate of degree of substitution (D.S.) about 0.4 was methylated in 91% to 96% yield by methyl iodide in ether or benzene to the corresponding white S-methyl xanthate. This S-methyl xanthate was partly hydrolyzed, less than 40% of the substituent being incidentally lost, and the hydrolyzate was chromatographed on paper. About 20% of glucose was recovered together with two substances recognized as characteristic hydrolytic products of glucose 6-S-methyl xanthate. The procedure was not quantitative for xanthate groups in the primary alcohol positions of cellulose, and was too drastic to yield information about the less stable groups in the secondary positions.The acetylation of the above cellulose S-methyl xanthate with acetic anhydride and pyridine led to a near-white, fibrous, fully acetylated product with unaltered xanthate substitution. Repeated attempts to remove the S-methyl xanthate groups by reaction with heavy metals or their salts, or with sodium chlorite, resulted in the simultaneous removal of about the same number of acetyl groups.
POLAROGRAPHY OF URANIUM: III. URANIUM(VI) IN FLUORIDE MEDIA
Authors: McEwen David J. , Vries Thomas De
Published: May 2006

The uranium(VI) and (V) polarographic waves were studied in chloride and perchlorate supporting electrolytes of 0.1 M to almost neutral acidities and containing 0 to 100 fold excess of fluoride. The concentrations of the uranium(VI)–fluoride species (UO2Fn+2−n, n = 1 − 4) were calculated and it is shown that the first two species, UO2F+ and UO2F2, are either reduced reversibly at the D.M.E., or dissociate rapidly to the uncomplexed ion, UO2++, which is known to reduce reversibly. The UO2F4− species, and possibly also UO2F3− is reduced irreversibly, and the rate constant of the electron transfer process, kf°, and the transfer coefficient, α, were calculated by two methods. The electrode reaction is proposed as UO2Fn+2−n+e− = UO2++nF−. The rate of disproportionation of uranium(V) was found to depend upon the F/U ratio, and the rate constants for the reaction were calculated.
PREPARATION OF GUANIDINE FROM AMMONIUM THIOCYANATE, SULPHUR DIOXIDE, AND AMMONIA UNDER PRESSURE
Authors: Boivin Jean L. , Tremblay Meude
Published: May 2006

Nearly quantitative yields of guanidine have been obtained by heating a mixture of ammonium thiocyanate, sulphur dioxide, and ammonia under moderate pressure. Guanidine is present chiefly as the sulphamate. When a molar ratio of ammonium thiocyanate, sulphur dioxide, and ammonia of 1:3:7 respectively was used, approximately one mole of guanidine sulphamate was produced together with half a mole of ammonium sulphate and more than two moles of elemental sulphur. The reaction products are in the molten state at the synthesis temperature, and with a suitable reactor capable of withstanding corrosion, the reaction has possibilities as a continuous process.
AN IONIZATION GAUGE DETECTOR FOR GAS CHROMATOGRAPHY
Authors: Ryce S. A. , Bryce W. A.
Published: May 2006

An ionization gauge has been modified to serve as a detector for gas chromatography. A small fraction of the effluent gas from the column is diverted into the gauge through an adjustable leak. The gauge is operated under conditions such that ionization of the eluted compound only occurs, and not of the helium carrier. The ion current is amplified and displayed on a pen recorder. The gauge combines very high sensitivity and rapid response with almost complete independence of changes in flow rate, pressure, or temperature.
1,1-DISUBSTITUTED-2-NITROGUANIDINES
Authors: McKay A. F. , Steyermark P. R.
Published: May 2006

not available
ADDITION OF n-BUTYL MERCAPTAN TO 1-PENTENE ON IRRADIATION WITH X-RAYS OR GAMMA RAYS: II. EFFECT OF RIGOROUS DRYING AND DEGASSING
Authors: Fontijn A. , Spinks J. W. T.
Published: May 2006

Butyl mercaptan reacts with 1-pentene when irradiated with X and gamma rays. Experiments on mixtures which had been rigorously degassed and dried suggest that the reaction kinetics are strongly dependent on traces of oxygen in the system. A possible mechanism for the reaction is given.
ADDITION OF n-BUTYL MERCAPTAN TO 1-PENTENE ON IRRADIATION WITH X-RAYS OR GAMMA RAYS: III. ENERGY DEPENDENCE, 140 KVP. TO 24.5 MEVP
Authors: Fontijn A. , Spinks J. W. T.
Published: May 2006

The effect of energy variation on the addition of n-butyl mercaptan to 1-pentene has been studied using radiations at 140 kvp., 1.25 Mev., and 24.5 Mevp. No appreciable energy dependence has been found over this range.
THE NORMAL C17 FATTY ACIDS OF MUSK-OX FAT
Authors: Chisholm Mary J. , Hopkins C. Y.
Published: May 2006

A sample of body fat of the Canadian musk ox (Ovibosmoschatus subsp.) was converted to methyl esters and distilled. The fraction containing esters of C17 acids was crystallized fractionally at low temperature and two straight-chain C17 acids were isolated. n-Heptadecanoic acid was identified by analysis, by mixed melting point of the acid and two derivatives with authentic samples, and by its X-ray diffraction pattern. 9-Heptadecenoic acid was identified by analysis, by mixed melting point of two derivatives with authentic samples, and by oxidative cleavage. It is estimated that the fat contained 1.7% of n-heptadecanoic acid and 0.9% of cis-9-heptadecenoic acid, based on the total fatty acids. Although there was an appreciable content of trans acids in the fat, the heptadecenoic acid was found to contain little or none of the trans form.
HYDROGENOLYSIS OF CARBOHYDRATES: III. FURTHER OBSERVATIONS ON THE REDUCTION OF METHYL α-D- GLUCOPYRANOSIDE
Authors: Rudloff E. Von , Tulloch A. P.
Published: May 2006

The hydrogenolysis of methyl α-D-glucopyranoside at 180° to 220 °C. was found to yield in addition to the polyols obtained at 240° substantial quantities of hydro-D-glucal (2-deoxy-1,5-anhydro-D-sorbitol), smaller amounts of 2-deoxymethyl glucoside, and the hitherto unknown hydro-D-altral, as well as trace amounts of several other unidentified deoxy-glycosides and 1,5-anhydrohexitols. These findings accordingly revise the reduction mechanism proposed earlier and show that inversion of one or more hydroxyl groups can occur during the hydrogenolysis.
ISOPIESTIC TECHNIQUES APPLIED TO PHASE DIAGRAM DETERMINATION IN THE SYSTEMS SILVER–CADMIUM AND COPPER–CADMIUM
Authors: Rayson H. W. , Alexander W. A.
Published: May 2006

not available
A CORRELATION OF ELECTRIC DIPOLE MOMENTS OF SUBSTITUTED BENZENES BY REACTIVITIES
Authors: Rao C. N. Ramachandra , Wahl Werner H. , Williams Edward J.
Published: May 2006

not available
THE ELECTRONIC SPECTRA OF CRYSTALLINE TOLUENE, DIBENZYL, DIPHENYLMETHANE, AND BIPHENYL IN THE NEAR ULTRAVIOLET
Authors: Coffman Robert , McClure Donald S.
Published: May 2006

The electronic absorption spectra of single crystals of toluene, dibenzyl, diphenylmethane, and biphenyl have been photographed at 20 °K. using polarized light in the range 3000 to 2500 Å. The fluorescence spectrum of biphenyl has also been examined. This is the first time that the excited states of biphenyl analogous to the B2u state of benzene have been observed. The main features of the spectra are similar for all four compounds, and the differences may be understood in terms of the weak coupling between the benzene rings of the "double molecules".
ENERGY TRANSFER IN MOLECULAR CRYSTALS AND IN DOUBLE MOLECULES
Authors: McClure Donald S.
Published: May 2006

The theory of the transfer of electronic energy between two molecules, or between two parts of a "double molecule", is discussed for the case in which vibrational quanta are present. The results are obtained for two limiting cases of weak and strong electronic interaction. Some of the phenomena occurring in the intermediate region are discussed qualitatively. With the aid of these results the spectra of biphenyl, diphenylmethane, and dibenzyl have been analyzed, and the electronic energy exchange parameter has been determined for each. These data are compared with similar data on durene crystal and the paracyclophanes. The electronic energy exchange parameter is given approximately correctly by considering the interaction of electronic transition dipoles except for very close and for very distant molecules.
SOME EFFECTS OF INTRAMOLECULAR VIBRATIONAL ENERGY TRANSFER IN COMPLEX FLUORESCENT MOLECULES
Authors: Stevens B.
Published: May 2006

The effects of intramolecular redistribution of vibrational energy on both the fate of an excited complex molecule and the appearance of its electronic spectra are discussed in terms of a three-dimensional energy surface. It is suggested that continuous absorption be used as a criterion for the application of classical methods to intra- and inter-molecular vibrational energy transfer in those cases where fluorescence emission is observed.
QUENCHING AND VIBRATIONAL-ENERGY TRANSFER OF EXCITED IODINE MOLECULES
Authors: Polanyi J. C.
Published: May 2006

Quenching of I2* [Formula: see text] (υ′ = 26) is shown to take place to the exclusion of vibrational-energy transfer in iodine at pressures up to 19 mm. A possible quenching mechanism involving sensitized predissociation of the collision partner is described. Vibrational transfer in collisions with H2 and D2 is found to occur at less than every gas kinetic collision. Arguments on general grounds are put forward to support this result, which conflicts with that of earlier workers. Increase in the mass of the isotope is found to bring about increased efficiency of vibrational transfer.
THE FLUORESCENCE AND ITS RELATIONSHIP TO PHOTOLYSIS IN HEXAFLUOROACETONE VAPOR
Authors: Okabe Hideo , Steacie E. W. R.
Published: May 2006

Hexafluoroacetone vapor, when excited at 25 °C by light of wavelength 3130 Å, gives rise to fluorescence. The fluorescence spectrum starts at about 3470 Å and extends to almost 6000 Å with a maximum at about 4200 Å, independent of pressure over the range 3 mm. to 170 mm. No fine structure is observed. Oxygen has almost no effect on the spectrum, contrary to the cases of acetone and biacetyl vapor, where oxygen causes a marked change. The absorption follows Beer's law between 5 mm. and 50 mm. of hexafluoroacetone pressure and the absorption coefficient has been measured.The fluorescence efficiency decreases slightly with the addition of less than 1 mm. of oxygen and there stays constant up to an oxygen pressure of 30 mm., indicating that the fluorescence may be principally from the short-lived singlet excited state. The fluorescence efficiency increases with pressure of hexafluoroacetone or with the addition of inert gases such as perfluorobutane, perfluoropropane, hexafluoroethane, or carbon dioxide. The present results may be compared with those of the photolysis, where it was found that the quantum yield of the decomposition decreases with increasing pressure and with added inert gases. A close relationship between the fluorescence and the photolysis suggests itself. A mechanism is proposed to explain the results, which assumes that the molecule is raised to the upper vibrational levels of a singlet excited state, and subsequently deactivated to the lowest vibrational levels of the same state, from which it fluoresces. On the basis of this mechanism it seems possible to correlate the photolysis with the fluorescence.
HYDROGEN ABSTRACTION REACTIONS OF DIPHENYLPICRYLHYDRAZYL
Authors: Brook A. G. , Anderson R. J. , Patot J. Tissot Van
Published: May 2006

The stable free radical diphenylpicrylhydrazyl (DPP•) has been found to react quantitatively with ammonia and hydrazine forming nitrogen and diphenylpicrylhydrazine, and less cleanly with hydroxylamine forming diphenylpicrylhydrazine and nitrous oxide. The reactions of DPP• with a variety of amines are not clean, in part owing to the formation of complexes of the amines with the reaction product diphenylpicrylhydrazine. Preliminary investigations of the reactions of DPP• with mercaptans have shown that these otherwise clean reactions have a variable stoichiometry, dependent on the concentration and other reaction conditions.
EXCHANGE BETWEEN THALLOUS AND THALLIC IONS IN THE PRESENCE OF SULPHATE ION
Authors: Wiles D. R.
Published: May 2006

The rates of the exchange reaction between thallous and thallic ions have been measured as a function of sulphate ion concentration, at constant acidity. At high sulphate concentrations, the results agree with those of Brubaker and Mickel, indicating second- and higher-order dependence of the rate on sulphate ion concentration. At low sulphate concentrations, pure first-order dependence on sulphate is found. The inhibitive effect found in some systems is absent. A bridge-transfer mechanism is suggested.
THE STUDY OF HYDROGEN BONDING AND RELATED PHENOMENA BY ULTRAVIOLET LIGHT ABSORPTION: PART I. INTRODUCTION
Authors: Forbes W. F. , Templeton J. F.
Published: May 2006

Hydrogen bonding, which is known to give rise to dimer formation in benzoic acids and similar compounds, may affect solution spectra by intermolecular and by intramolecular bond formation. Generally environmental factors affecting absorption spectra can be conveniently divided into three types: intermolecular hydrogen bonding between solute molecules only; intermolecular hydrogen bonding between solute and solvent molecules; and environmental effects not involving the formation of hydrogen bonds.Distinct evidence for these types of interaction is deduced from ultraviolet spectra, and various implications of the spectral analyses are discussed.
CRITICAL CONCENTRATION EFFECTS IN POLYMER–POLYMER–SOLVENT SYSTEMS
Authors: Bigelow C. C. , Cragg L. H.
Published: May 2006

In various ternary systems of the type polymer A – polymer B – solvent S, a dip or peak has been observed in the [η] – cB curve at the critical concentration of polymer B. ([η] is the intrinsic viscosity of A in mixed solvent consisting of B and S, and cB is the concentration of B in this mixed solvent.) It is shown that such a critical concentration effect is most likely to occur when the solvent is poor for polymer B, and will be the larger the poorer the solvent.Evidence is also presented in support of the hypothesis that if, as is usual, the two polymers repel each other, the effect is a dip if the solvent is good for polymer A and is a peak if the solvent is sufficiently poor for polymer A.Critical concentrations of polystyrene, polyvinyl acetate, and polymethyl methacrylate (five different samples) have been measured in this way in 12 different ternary systems. These observed critical concentrations are in good agreement with values calculated using the equation previously described, according to which the critical concentration of a polymer is inversely proportional to its intrinsic viscosity in the solution.
AMMONOLYSIS OF 1,2-EPOXYCYCLOHEXANE AND TRANS-2-BROMOCYCLOHEXANOL
Authors: Hawkins L. R. , Bannard R. A. B.
Published: May 2006

Optimum conditions for the preparation of trans-2-aminocyclohexanol by ammonolysis of 1,2-epoxycyclohexane or trans-2-bromocyclohexanol are realized by use of a 20-fold excess of aqueous alcoholic ammonia at 100°. Under these conditions formation of secondary amines is minimized. Lower ammonia–reactant ratios, or the use of absolute methanolic ammonia or aqueous ammonia, lead to lower yields of primary amine and higher yields of secondary amines. 1,2-Epoxycyclohexane has been isolated from the interaction of trans-2-bromocyclohexanol with aqueous ammonia. The oxide reacts more rapidly with aqueous alcoholic ammonia than the bromohydrin and the rate of conversion of the latter to amine is thus controlled by the rate of conversion of bromohydrin to oxide.
CONFORMATIONAL EFFECTS AND THE INFLUENCE OF PRESSURE ON REACTION RATES
Authors: Whalley E.
Published: May 2006

It has been suggested that the pressure coefficient of the rate constant of some reactions may be influenced by the formation of intermolecular or intramolecular conformations prior to reaction. This has been examined theoretically and the relevant experimental evidence has been discussed. No examples of an effect in which the conformations are at equilibrium are known with certainty, but the effect of pressure on termination in the polymerization of styrene appears to be an example of a conformational effect when the conformations are not at equilibrium.The pressure coefficient of the rate constant for the isomerization of citraldehyde to 3,8-carvomenthenediol is not consistent with a unimolecular slow step, but it is consistent with either a bimolecular or a termolecular slow step. It is pointed out that the pressure coefficient of rate constants may be very useful in determining the molecularity of some reactions.
THE PHOTOCHEMICAL OXIDATION OF ALDEHYDES IN THE GASEOUS PHASE: PART III. THE ABSOLUTE VALUES OF THE VELOCITY CONSTANTS FOR THE PROPAGATING AND TERMINATING STEPS IN THE PHOTOCHEMICAL OXIDATION OF ACETALDEHYDE AND PROPIONALDEHYDE
Authors: McDowell C. A. , Sharples L. K.
Published: May 2006

It has been established (Parts I and II) that the photochemical oxidation of acetaldehyde and propionaldehyde obeys the kinetic expression[Formula: see text]where RCHO represents the aldehyde and RCO3H the corresponding peracid. k3 is the velocity constant for the propagating reaction, and k6 that for the terminating reaction involving the mutual interaction of two RCO3 radicals. [Formula: see text] represents the rate of initiation of the photooxidation.Alcohols have been found to retard the photooxidation and it has been shown that the retarded reaction obeys the kinetic expression:[Formula: see text]It has thus been possible to determine the rates of initiation [Formula: see text] for each of the photooxidations. Application of the rotating sector technique has enabled the lifetime of the oxidation chains to be measured. These data together with the information given in Parts I and II have been used to calculate the absolute values for the velocity constants for the propagating and terminating reactions, k3 and k6:[Formula: see text]in the gas-phase photooxidations of acetaldehyde and propionaldehyde.The values of the respective velocity constants are: acetaldehyde at 20°, k3 = 8.05( ±2.04) × 103 1. mole−1 sec−1, k6 = 8.93( ±4.20) × 1010 1. mole−1 sec−1; propionaldehyde at 22°, k3 = 4.35( ±0.9) × 104 1. mole−1 sec−1, k6 = 2.69( ±1.35) × 1010 1 mole−1 sec−1.These values for the velocity constants for the "recombination" reactions of the peracetic and perpropionic radicals indicate that for these radicals reaction [6] is very efficient.
ULTRAVIOLET IRRADIATION OF PYRIMIDINE DERIVATIVES: II. NOTE ON THE SYNTHESIS OF THE PRODUCT OF REVERSIBLE PHOTOLYSIS OF URACIL
Authors: Moore A. M.
Published: May 2006

not available
AN ALTERNATIVE SYNTHESIS OF 2-O-METHYL-D-XYLOSE
Authors: Bowering W. D. S. , Timell T. E.
Published: May 2006

not available
THE REACTION OF CARBON DISULPHIDE WITH ALUMINA
Authors: Pinkus A. G. , Kim J. S.
Published: May 2006

The absorption spectrum in aqueous solution of the yellow substance formed by the reaction of carbon disulphide and alumina exhibits absorption maxima at 398 and 325 mμ. This yellow color is not due to sodium disulphide as previously proposed since the latter substance showed an entirely different spectrum with shoulders at about 360–375 mμ and 290–300 mμ. The presence of both water and sodium hydroxide in the alumina is necessary for the formation of the yellow color in confirmation of previous work. A study of the gain in weight of the alumina with time of contact with carbon disulphide showed that this reaction begins to level off after about 24 hours. A minimum value for the heat evolved for the alumina–carbon disulphide system was determined as 8.6 cal. per g. of alumina reacting with an excess of carbon disulphide.
THE PHOTOLYSIS OF METHYL CYANIDE AT 1849 Å
Authors: McElcheran D. E. , Wijnen M. H. J. , Steacie E. W. R.
Published: May 2006

The photolysis of MeCN has been investigated under a considerable range of conditions and a mechanism proposed which accounts satisfactorily for the products found, viz. H2, HCN, C2N2, CH4, C2H6, C2H5CN. Two primary processes occur[Formula: see text]of which the former is apparently the more important. HCN is formed predominantly by an H atom abstraction of the CN group which is believed to occur through addition to the unsaturated bond with the formation of an unstable inline radical. This and similar intermediates formed by other radicals are proposed to account for several anomalies found in the photochemistry of nitriles.A brief investigation of the photolysis of carbonyl cyanide is reported.
THE LIMITING EQUIVALENT CONDUCTANCES OF AMMONIUM CHLORIDE, AMMONIUM BROMIDE, AND AMMONIUM NITRATE AT 35.00 °C.
Authors: Campbell A. N. , Bock E.
Published: May 2006

The limiting equivalent conductances of ammonium chloride, ammonium bromide, and ammonium nitrate as well as the limiting ionic conductances of the ammonium and nitrate ions were determined at 35 °C. with a probable error of 0.05%. The values found were [Formula: see text] 180.97 mhos, [Formula: see text] 182.73 mhos, [Formula: see text] 174.21 mhos, [Formula: see text] 88.73 mhos, and [Formula: see text] 85.48 mhos. These values were obtained by the application of the Shedlovsky method of extrapolation to equivalent conductance data, which had been corrected for the hydrolysis of the ammonium ion.Observed equivalent conductances of aqueous solutions of ammonium nitrate at 35 °C., in the concentration range from 0.0002 N to 10 N, have been compared with those calculated by means of the Wishaw–Stokes and Falkenhagen–Leist equations. The Wishaw–Stokes equation was found to give better agreement with experiment than the Falkenhagen–Leist equation.
(—)-HOMOSTACHYDRINE, A NEW ALKALOID ISOLATED FROM THE SEEDS OF MEDICAGO SATIVA L. GRIMM
Authors: Wiehler Gerhard , Marion Léo
Published: May 2006

The seeds of Medicago sativa (alfalfa) have previously been shown to contain other bases besides stachydrine. One of these bases has now been isolated and found to be a homologue of stachydrine for which the name homostachydrine is suggested. (—)-Homostachydrine is shown to be identical with the (—)-methyl betaine of pipecolic acid. The synthetic racemate of the betaine of pipecolic acid has similar properties to homostachydrine, and their infrared spectra and X-ray powder diagrams are identical.
TRYPTAMINES, CARBOLINES, AND RELATED COMPOUNDS: PART IV. ATTEMPTED SYNTHESIS OF THE PHYSOSTIGMINE RING SYSTEM
Authors: Abramovitch R. A.
Published: May 2006

4-Methylpiperid-2,3-dione-3-phenylhydrazone failed to undergo ring closure under Fisher–cyclization conditions but rearranged to a more stable form of the phenylhydrazone. Cis–trans isomerism is suggested for the two forms.
COEXISTENCE PHENOMENA IN THE CRITICAL REGION: V. THE GRAVITY EFFECT IN THE BINARY LIQUID SYSTEM ANILINE-CYCLOHEXANE FROM LIGHT SCATTERING
Authors: Murray F. E. , Mason S. G.
Published: May 2006

Transmittance measurements were used to investigate vertical concentration gradients, at temperatures slightly above the critical, in a binary liquid system. The gradients, which are predicted theoretically, did not begin to form during time intervals of several hours. It was found that a theoretical relation between transmittance and concentration gradient did not apply, even qualitatively, to the results obtained. The significance of these observations is discussed.
PHOTOOXIDATION OF KETONES IN AN O18 ENRICHED ENVIRONMENT
Authors: Dunn J. R. , Kutschke K. O.
Published: May 2006

A technique is described in which the origins of the products of photooxidation of ketones can be obtained in respect to whether they arise from the carbonyl or the alkyl groups of the ketone molecule. This is accomplished with the use of reactant molecular oxygen which has been enriched in the O18 isotope. Application of this to the photooxidation of acetone indicates that a large fraction of the carbon dioxide contains the carbonyl group of the ketone and that acetyl radicals play an important role in the oxidation to temperatures at least as high as 175 °C. Propionyl radicals are much less stable, and, in the photooxidation of diethyl ketone, their reactions, other than decomposition, appear to be negligible at quite low temperatures. Some comment is made on the mechanisms of these photooxidations.
SUR LA TRANSFORMATION DE LA DIHYDROHÉTÉROCONESSINE EN DIHYDROCONESSINE
Authors: Favre H. , Marinier B.
Published: May 2006

not available
THE CHEMISTRY OF PEAT PART: I. THE STEROLS OF PEAT MOSS (SPHAGNUM)
Authors: Ives D. A. J. , O'Neill A. N.
Published: May 2006

Peat moss (Sphagnum) from the surface of an Atlantic peat bog has been extracted with a mixture of benzene and ethanol. The extract has been fractionated chromatographically on alumina. A mixture of sterols has been isolated from one fraction. This mixture has been proved by oxidation experiments to consist of β-sitostanol (stigmastanol) and β-sitosterol. It constituted approximately 0.2% by weight of the dried peat moss.
ORGANIC DEUTERIUM COMPOUNDS: XIX. SYNTHESIS OF SOME DEUTERATED LAURIC ACIDS AND THEIR METHYL ESTERS
Authors: Isabelle M. Elaine , Leitch L. C.
Published: May 2006

The synthesis of lauric acids deuterated in the carboxyl, the terminal methyl, and the α-methylene groups and in various combinations of these is described. The methyl and methyl-d3 esters of each of the acids were also prepared.Two further examples of homolytic halide addition to olefins are reported.The reaction between alkyl halides and silver acetylides is described. A mechanism involving a new type of free radical is postulated.
A STUDY OF THE CONDUCTIVITY OF CERTAIN ACIDS AND ALKALI HALIDES IN GLYCOL AND THE INFLUENCE OF THE ADDITION OF A SECOND SOLVENT
Authors: Kirby P. , Maass O.
Published: May 2006

The conductivities of HCl, H2SO4, HNO3, and a number of their alkali metallic salts were measured in ethylene glycol. The influence of the addition of water, methanol, and hydrogen peroxide was determined. The results are discussed on the basis of well-known theories of electrolytic conductivity involving H+ ions.
D-APIOSE
Authors: Gorin P. A. J. , Perlin A. S.
Published: May 2006

Naturally-occurring apiose is shown by synthesis to be the D-isomer in the open-chain form. In this synthesis 3-O-benzyl-D-fructose is cyanohydrated and the resulting heptonic lactones are reduced to 3-O-benzyl-2-C-(hydroxymethyl)-D-arabo-hexitol. The latter is oxidized with lead tetraacetate affording 2-O-benzyl-3-C-(hydroxymethyl)-D-glycero-tetrose which, on debenzylation, gives 3-C-(hydroxymethyl)-D-glycero-tetrose (D-apiose).
SYNTHESIS OF SOME HEXANEDIOLS
Authors: Rudloff E. von
Published: May 2006

A general method for the preparation of 1,3-, 1,4-, and 1,5-hexanediols is described. The synthesis involves the preparation of a corresponding ketohexanoate, which is reduced to the diol with lithium aluminum hydride. Countercurrent distribution was found useful in the purification of small amounts of intermediates and end products. 1,2-, 1,6-, and 2,5-hexanediols were also prepared by known procedures. The infrared spectra of these diols have been recorded and their p-nitrobenzoates were prepared.
METHYLATION OF SUGAR MERCAPTALS: I. INTRODUCTION AND D-GLUCOSE DIETHYL MERCAPTAL
Authors: Dutton G. G. S. , Yates K.
Published: May 2006

The methylation of the diethyl mercaptals of D-glucose, D-mannose, D-galactose, and L-arabinose in methyl iodide has been re-examined. The apparent lack of reactivity of the last three has been shown to be due to their insolubility in methyl iodide since appreciable methylation occurs in tetrahydrofuran. The case of D-glucose diethyl mercaptal has been examined in some detail and although polysubstitution occurs on reaction with methyl iodide in tetrahydrofuran the only monomethyl derivative formed is the 2-O-methyl ether. Preliminary work suggests that this is not the case with D-mannose mercaptal.
SOME ANOMALOUS ELECTRICAL POLARIZATIONS
Authors: Podleschka Peter , Westland Liselotte , Wright George F
Published: May 2006

Dielectric-constant determinations of a series of solids previously reported to have high atom polarizations have not confirmed earlier opinions. Moreover, when it has been practicable to determine the change in polarization with respect to temperature, the relationship is not invariant. This variation may be, and in some instances should be, interpreted as evidence for orientation polarization. However, all such assignments cannot be certain until the change in solid dielectric constant with respect to temperature has been studied.
SYNTHESIS OF 4-AMINOBUTYRIC ACID AND 2,4-DIAMINOBUTYRIC ACID FROM BUTYROLACTONE
Authors: Talbot Guy , Gaudry Roger , Berlinguet Louis
Published: May 2006

The ring opening of γ-butyrolactone with 1 mole of potassium phthalimide and the hydrolysis of the intermediate product gave 4-aminobutyric acid with an excellent yield. The condensation of 1 mole of potassium phthalimide with 2-bromo-4-butyrolactone gave a 2-phthalimidolactone which can also be opened by treatment with a second molecule of potassium phthalimide. This diphthalimido acid when hydrolyzed gave, with an excellent yield, 2,4-diaminobutyric acid dihydrochloride.