bluuebunny/crossref_metadata_2025 huggingface dataset:
DIFFUSION COEFFICIENTS OF O AND N ATOMS IN INERT GASES
Authors: Morgan J. E. , Schiff H. I.
Published: May 2006

The diffusion coefficients of atomic oxygen in O2, N2, Ar, and He, and of atomic nitrogen in N2, have been measured as a function of pressure and temperature, using a previously described method.The rigid sphere collision diameters of atomic oxygen and atomic nitrogen at 280 °K were calculated as 2.65 Å and 2.75 Å respectively. The temperature dependence of the diffusion coefficients of O in O2 and N in N2 yielded the following Lennard-Jones parameters:[Formula: see text]
GAS–SOLID EXCHANGE STUDIES BY THE FLOW METHOD: Zn–ZnS AND Zn–ZnO REACTIONS
Authors: MacKinnon Allan J. , Martin Ronald R. , Secco E. A.
Published: May 2006

The initial exchange of zinc vapor with polycrystalline zinc oxide and zinc sulphide has been studied by a flow method under different conditions of zinc vapor flow rates and temperature. The exchange rate was found to be independent of flow rate. Kinetic and mechanism interpretations of these results along with existing data from exchange studies by the static method are discussed.
ADSORPTIVE AND GAS CHROMATOGRAPHIC PROPERTIES OF VARIOUS CATIONIC FORMS OF ZEOLITE X
Authors: Habgood H. W.
Published: May 2006

Gas chromatographic retention volumes for O2, N2, CH4, C2H6, C3H8, C4H10, C2H4, and C3H6 have been measured over a range of temperatures between 25 and 400 °C, on columns of the following ion-exchanged forms of zeolite X: Li+, Na+, K+, Mg++, Ca++, Ba++, and Ag+. In addition, for AgX zeolite, full isotherms have been determined for O2, N2, C2H6, and C2H4; and for NaX zeolite, isotherms for C2H6 and C2H4. The gas chromatographic retention volumes agree well with the isotherms in the case of NaX but are significantly low for AgX, presumably as the result of at least a portion of the adsorption process being slow. The heats of adsorption on NaX agree well with literature values for O2, N2, CH4, and C2H6 but are low for C3H8 and C4H10; further indication of slow processes and hence of a limitation of the g.c. technique. The observations can be correlated qualitatively in terms of the interplay of the following effects: (a) cationic field increases with decreasing ionic radius; (b) shielding of smaller cations is greater—at least in the six-membered oxygen-ring sites; (c) divalent cations, while having greater fields, are only half the number of monovalent cations and tend to be found in less exposed sites; and (d) the polarizing power of silver ion, which also occupies all types of exposed sites, is very strong. The most intense interactions were found with AgX; with ethylene a much stronger complex is formed than has been reported for any other silver compound. The significance of molecular quadrupole interactions on these heteroionic surfaces is shown by the much weaker cationic effects observed with O2 (which has negligible quadrupole moment) than with nitrogen.
QUANTITATIVE DECARBOXYLATIONS OF ELECTRONEGATIVELY SUBSTITUTED BENZOIC ACIDS VIA THE SCHMIDT REACTION
Authors: McNamara A. J. , Stothers J. B.
Published: May 2006

not available
LA RÉACTION DU SULFURE DE BORE AVEC LES ALCOOLS
Authors: Lalancette J. M.
Published: May 2006

not available
PROTON MAGNETIC RESONANCE CHEMICAL SHIFTS OF THE S-METHYL GROUP
Authors: Pettit George R. , Douglass Irwin B. , Hill Ralph A.
Published: May 2006

not available
AN ALTERNATIVE SYNTHESIS OF 5-CARBOXYVANILLIN
Authors: Morita Hirokazu
Published: May 2006

not available
THE REARRANGEMENT OF 2,4-DIMETHYLTHIAZOLE 3-OXIDE WITH ACETIC ANHYDRIDE
Authors: Anderson Hugh J. , Barnes Douglas J. , Khan Zahir M.
Published: May 2006

The rearrangement in acetic anhydride of 2,4-dimethylthiazole 3-oxide has been found to produce 2-acetoxymethyl-4-methylthiazole and 4-acetoxymethyl-2-methylthiazole in the ratio of about 4.5 to 1. The same type of rearrangement with 4-methylthiazole 3-oxide gave both 4-acetoxymethylthiazole and 2-acetoxy-4-methylthiazole, but in poor yields. The structure of the sulphate salt of 2,4-dimethylthiazole 3-oxide has been established.
ION–MOLECULE REACTIONS STUDIED BY TIME-OF-FLIGHT MASS SPECTROMETRY: II. REACTIONS IN CO–D2 AND CH4–D2 MIXTURES
Authors: Hand Clifford W. , Weyssenhoff Hanns von
Published: May 2006

The pulsed operation capability of the time-of-flight mass spectrometer has been used for the study of ion–molecule reaction kinetics. Reactions take place in a high-pressure (up to 0.08 Torr) region free from external electric fields, and time is used as a direct kinetic variable. The following reactions were studied.[Formula: see text]In CH4–D2 mixtures a reaction in addition to CH4+ + CH4 → CH5+ + CH3 leads to the formation of an ion of m/e 17. Various possibilities for this reaction are discussed.
KINETICS OF THE CATALYZED HYDROLYSIS OF p-NITROPHENYL ACETATE
Authors: Sacher E. , Laidler K. J.
Published: May 2006

Catalytic constants have been determined for the hydrolysis at 20 °C of p-nitrophenyl acetate in 9.56% (w/w) dioxane–water mixtures; catalysts used were hydroxide ions, imidazole and 2-methylimidazole, various substituted pyridines, serine, histidine and histidylhistidine. In the case of hydroxide ion catalysis, the rate constant falls off at high catalyst concentrations, and this is attributed to the establishment of an equilibrium involving the anion of the substrate. The results with the various catalysts indicate that there is no simple correlation between catalytic efficiency and pK or nucleophilicity. In the imidazole series there is evidence of steric hindrance when a group is present in a position next to the functional group. There is an indication of bifunctional catalysis in the hydrolysis by 2-(β-hydroxyethyl)pyridine and 4-(γ-hydroxypropyl)pyridine, both of which are much more effective than pyridine.
THE METAL-CATALYZED AUTOXIDATION OF TETRALIN: IV. THE EFFECT OF SOLVENT AND TEMPERATURE
Authors: Kamiya Y. , Ingold K. U.
Published: May 2006

The limiting rate of oxidation of tetralin catalyzed by cobalt, manganese, and copper decanoates has been measured in 12 solvents at 65 °C. This rate is generally determined by the kinetic condition that the hydroperoxide reaches a steady-state concentration but the experimental rates are smaller than expected in some solvents. Both cobalt and manganese are able to terminate reaction chains and they therefore act as inhibitors of the oxidation at high concentrations. The ratio of the propagation rate constant (k3) to the square root of the termination rate constant (k6) for the oxidation of tetralin in acetic acid solution is given by[Formula: see text]
THE PHOTOLYSIS OF FORMALDEHYDE-d2, FORMALDEHYDE AND THEIR MIXTURES
Authors: Venugopalan M. , Kutschke K. O.
Published: May 2006

It has been verified that H atoms are formed when formaldehyde vapor at 300 °C is illuminated by the 3 655 Å group of the mercury arc. Isolation of the group of lines was achieved by a combination of glass and solution filters. This observation gives further support to the "high" value of D(H—CO).It was found that D2CO also is predissociated following absorption at this wavelength. This observation is not in agreement with predictions based on purely spectroscopic studies of these molecules.
LYCOPODIUM ALKALOIDS: XV. STRUCTURE AND MASS SPECTRA OF SOME MINOR ALKALOIDS OF L. FLABELLIFORME
Authors: Alam S. N. , Adams K. A. H. , MacLean D. B.
Published: May 2006

Hydroxy-des-N-methyl-α-obscurine, C16H24O2N2, has been isolated from L. flabelliforme and a structure assigned to it on the basis of physical evidence. A structure is assigned to Lycopodium alkaloid L.5, which we have named flabellidine, on the basis of physical evidence and its chemical derivation from lycodine. The mass spectra of hydroxy-des-N-methyl-α-obscurine, flabellidine, and flabelline are discussed.
MECHANISM OF THERMAL DECOMPOSITION OF AMMONIUM METAVANADATE
Authors: Taniguchi M. , Ingraham T. R.
Published: May 2006

When ammonium metavanadate is roasted at 225 °C, ammonia and water are eliminated in the ratio 2:1 and an intermediate compound identified by weight loss and chemical analysis as (NH4)2•O•V2O5• is formed. An X-ray diffraction pattern for this material is reported. Transpiration experiments have been used to establish the free energy of this reaction. The second stage of the decomposition involves an endothermic and an exothermic process, both of which occur with the production of a gaseous product. The liberation of ammonia is not quantitative, and its oxidation on the vanadium pentoxide, in the last stage of decomposition, is suggested as a possible source of the exothermic heat.
THE SIGNIFICANCE OF HALIDE IN GRIGNARD REAGENTS
Authors: French Warren , Wright George F
Published: May 2006

The optical activity of 1-phenylethanol from benzaldehyde and methyl chloride Grignard reagent coordinated with (+)2,3-dimethoxybutane is about one fourth of that found for the same product when bis-methylmagnesium is the reagent. The difference has been attributed to the relative coordinating power of magnesium chloride versus the optically active ether.
THE PRESENCE OF EXCITED MOLECULES IN ACTIVE NITROGEN
Authors: Dunford H. B. , Milton E. R. V. , Whalen D. L.
Published: May 2006

Spectra of active nitrogen have been photographed under conditions comparable to those used for most studies of reactions of active nitrogen with other molecules. Bands observed were identified as the first positive system of nitrogen and the β- and γ-bands of nitric oxide. No trace of Vegard–Kaplan emission was observed. The 2 537 line of mercury was detected under certain conditions.The results are used to rationalize the large discrepancy which exists between estimates of the lifetime of N2(A3Σu+) by optical spectroscopy and reaction kinetics. In the former method, the measurements are performed in an oxygen-free system and are clearly related to a radiative lifetime. In the latter method, the measurements are performed in the presence of traces of oxygen and are believed to indicate a collisional lifetime. The reaction kinetic measurements are shown to be in complete agreement, both with regard to decay kinetics and lifetime, with electron spin resonance measurements on active nitrogen produced under near-identical conditions.
LYCOPODIUM ALKALOIDS: VII. LYCODOLINE (ALKALOID L.8)
Authors: Ayer W. A. , Iverach G. G.
Published: May 2006

Lycodoline (alkaloid L.8) is shown to have the structure and stereochemistry depicted in II. The transformation of lycodoline into lycopodine is described. The use of infrared spectroscopy in assigning the configuration at C-12 and the nitrogen in these and related alkaloids is described. The effect of the configuration at C-12 on the optical rotatory dispersion spectra and on the mass spectra of lycopodine (I) and 12-epilycopodine (X) is discussesd.
THE SYNTHESIS OF 3-O-[(BENZYLTHIO)CARBONYL]-β-D-GLUCOPYRANOSE AND METHYL 2,4,6-TRI-O-BENZOYL-α AND β-D-GLUCOPYRANOSIDES
Authors: Wlllard J. J. , Brimacombe J. S. , Brueton R. P.
Published: May 2006

The discovery that the (benzylthio)carbonyl group is stable in concentrated hydrochloric acid has permitted the removal in that medium of isopropylidene blocking groups from 3-O-[(benzylthio)carbonyl]-1,2;5,6-di-O-isopropylidene-α-D-glucofuranose to furnish crystalline 3-O-[(benzylthio)carbonyl]-β-D-glucopyranose. Benzoylation of the latter provided a derivative which has made possible the synthesis of methyl 2,4,6-tri-O-benzoyl-α and β-D-glucopyranosides.
THE REACTIVITY OF THE CYCLIC POLYENES TOWARDS FREE RADICALS: I. COPOLYMERIZATION WITH ACRYLONITRILE
Authors: Ferdinandi E. S. , Garby W. P. , James D. G. L.
Published: May 2006

Cyclohexadiene-1,3 and bicyclo[2.2.1]heptadiene-2,5 each (B) copolymerize with acrylonitrile (A) in bulk at 60 °C in the presence of 0.01 M benzoyl peroxide. The copolymerization parameters for cyclohexadiene-1,3 are rA = 0.026 ± 0.014,rB = 0.20 ± 0.01, QB = 1.76, eB = −1.18; for bicycloheptadiene the parameters are rA = 0.65 ± 0.02, rB = 0.47 ± 0.08, QB = 0.27, eB = 0.03; limits of error are given at the 10% probability level. Cycloheptatriene and cyclooctatetraene inhibit the polymerization of acrylonitrile under similar conditions over a wide range of concentration. These results are discussed in terms of the general reactivity of the cyclic polyenes and of the behavior of structurally related monomers in polymerization, and a consistent pattern of reactivity emerges.
RAMAN SPECTRA AND VIBRATIONAL ASSIGNMENTS FOR TWO FORMS OF TETRAPHENYL CYCLOTETRAPHOSPHINE
Authors: Amster R. L. , Henderson W. A. , Colthup N. B.
Published: May 2006

Raman spectra have been obtained and vibrational assignments made for two isomeric compounds of tetraphenyl cyclotetraphosphine. The asymmetric P4 ring stretch has been identified near 500 cm−1 while the symmetric ring-breathing vibration most probably mixes with other low-frequency motions and is not explicitly assigned.
LYCOPODIUM ALKALOIDS: XVI. ANNOTINE
Authors: Szarek W. A. , Adams K. A. H. , Curcumelli-Rodostamo M. , MacLean D. B.
Published: May 2006

Annotine, C16H21O3N, is shown to be pentacyclic and to contain a tertiary hydroxyl group, a lactone function, a tertiary nitrogen atom, and a dialkylated double bond. The position of the double bond and the tertiary hydroxyl group relative to the nitrogen atom has been established by Emde degradation of annotine methiodide. The presence of a lactone function is inferred from the reduction of annotine to dihydroannotinol, a hemiacetal, which reacts with 1 mole of ethyl mercaptan. The reduction of the lactone to a diol in an annotine derivative has been carried out. The chemical studies and the examination of annotine and its derivatives by modern instrumental methods allow the assignment of a plausible structure to the alkaloid.
ESSENTIAL OILS AND THEIR CONSTITUENTS: XXII. DETECTION OF NEW TRACE COMPONENTS IN OIL OF GINGER
Authors: Nigam M. C. , Nigam Ishwar C. , Levi Leo , Handa K. L.
Published: May 2006

Oil of ginger was found to contain the following, as yet unreported, constituents—cumene, β-pinene, myrcene, p-cymene, γ-selinene, β-elemene, 2-heptanol, 2-nonanol, and bornyl acetate. The presence of 2 alcohols, for which gas chromatographic and infrared criteria of identity were determined, was also demonstrated. These data are important for establishing the authenticity of the essential oil.
UNIT CELL DIMENSIONS AND SPACE GROUPS OF SYM-DIPHENYL THIOUREA AND SYM-DIPHENYL UREA
Authors: Kari Roy , Kunchur N. R.
Published: May 2006

not available
THE STRUCTURES AND ABSOLUTE CONFIGURATIONS OF ANHYDRODEOXYHEPTITOLS
Authors: Camerman A. , Koch H. J. , Rosenthal A. , Trotter J.
Published: May 2006

not available
REACTIONS WITH DIAZOALKANES III. 1,4-NAPHTHAQUINONE AND DIAZOALKANES
Authors: Awad William Ibrahim , Boulos Alfred
Published: May 2006

The addition of diazomethane to 1,4-naphthaquinone has been reexamined. Two products are isolated from this reaction, one of them (IIIa) has been previously reported. Similarly, diazoethane gives two products. The constitution of these products is discussed, particularly in the light of their ultraviolet and infrared spectra. The thermal stability of diazoalkane adducts to I is discussed.
STEROIDS: VIII. SOME REACTIONS OF THE 3-METHYLCHOLEST-5-EN-3-OLS AND THEIR DERIVATIVES
Authors: Just G. , Tullio V. Di
Published: May 2006

The preparation and ethanolysis of 3-methylcholesteryl derivatives is described. It was noticed that Δ5-3-methyl-3-oxygenated steroids undergo hydrogenolysis, which can be suppressed by addition of sodium nitrite.
THE REACTIONS OF FREE RADICALS WITH NITROUS OXIDE
Authors: Bell T. N. , Kutschke K. O.
Published: May 2006

A study of the reactions of methyl, ethyl, and trifluoromethyl radicals with nitrous oxide has shown that each radical causes the formation of nitrogen at temperatures below 400°. It is believed that the oxygen abstraction reaction occurs.[Formula: see text]A semiquantitative study of the reaction of trifluoromethyl with nitrous oxide has been made, and difficulties in studying this type of reaction quantitatively are discussed.
PROTONATED CARBONYL GROUPS: IV. N,N-DIMETHYLACETAMIDE SALTS
Authors: Cook Denys
Published: May 2006

The infrared spectra of N,N-dimethylacelamide salts have been recorded and are consistent with protonation at the oxygen atom, vOH is between 2 095 and 3 360 cm−1 depending on the anion. The average value of the two components of the OH in-plane hydrogen-bending mode, δOH, is 1 253 cm−1 (splitting of about 147 cm−1 due to correlation field effects). The out-of-plane hydrogen-deformation mode occurs at 928 to 761 cm−1 depending on the salt. The 1 680 and 1 400 cm−1 bands which are present in all the salts are associated chiefly with stretching the CN and CO bonds respectively, in the OCN group, though it is likely that the vibrations are somewhat mixed.Some salts of complex acids are of the 2 base: 1 acid variety with very strong broad absorption centered near 900 cm−1, containing sharp transmission windows.
THE ALUMINIUM – ALUMINIUM BROMIDE AND ALUMINIUM – ALUMINIUM IODIDE SYSTEMS
Authors: Thonstad Jomar
Published: May 2006

The Al–Al2Br6and Al–Al2I6binary systems have been investigated by cryoscopy and solubility measurements. Pure Al2BrGmelts at 98.01 ± 0.02 °C; the eutectic is found at 97.91 ± 0.02 °C and 0.017 wt. % Al; at 254 °C the solubility of aluminium increases to 0.0195 wt. %. Pure Al2I6melts at 188.32 ± 0.02 °C; the eutectic is found at 188.17 ± 0.02 °C and 0.018 wt. % Al; at 320 °C the solubility increases to 0.021 wt. % Al. From the results it is concluded that dissolved aluminium is present in the melt either as Al20dimer species or as associated molecules of Al4Br6and Al4I6.
DENSITY AND VISCOSITY OF THALLIUM AMALGAMS
Authors: Foley William T. , Basak Arun K. , Delorey John R.
Published: May 2006

The densities of thallium amalgams were measured at 25, 50, 70, 90,105, 125, and 160 °C over the concentration range 0 to 42% thallium by weight and the results were fitted to equations of the form d = a + bx + cx2, where d is the density in grams per ml, a, b, and c are constants and x is weight % thallium in the amalgam. The coefficient of expansion was calculated for the temperature range 25 to 90 °C. Viscosities relative to mercury were also determined over the same range of composition and at the same temperatures as were used in the density measurements. Equations were presented which show the variation of viscosity with composition and also the variation of viscosity with temperature.
THE SYNTHESIS AND REACTIONS OF DIVINYL CARBONIUM IONS
Authors: Sorensen T. S.
Published: May 2006

A number of alkyl-substituted trienes have been protonated. In some cases, the existence of divinyl carbonium ions can be shown, while in others, a cyclization reaction leading to, cyclopentenyl carbonium ions takes place so rapidly that the presumed initially formed divinyl carbonium is never observed. Steric arguments are invoked to explain these differences. Complete n.m.r. and ultraviolet spectral data are presented in support of the assigned carbonium-ion structures. Some evidence has been obtained regarding the mechanism of the cyclization reaction. Finally, one of the cyclic carbonium ions is decomposed and the cyclic dienes which are produced are isolated and characterized.
PHOTOCHEMICAL TRANSFORMATIONS OF DIENES: IV. THE STEREOCHEMISTRY OF THE PHOTO-INDUCED ETHANOL ADDITION TO 3-METHOXYCHOLESTA-3,5-DIENE
Authors: Leznoff Clifford C. , Just George
Published: May 2006

The photolysis of 3-methoxycholesta-3,5-diene in ethanol-d resulted in a 1:1 mixture of 4α- and 4β-deuterio-3β-ethoxy-3α-methoxycholest-5-ene (II, IIa). A stereospecific synthesis of 4β-deuterio-3α,5-cyclo-5α-cholestan-6β-ol is described.
AGENTS AFFECTING LIPID METABOLISM: XIII. THE SYNTHESIS OF 1,4-DISUBSTITUTED BICYCLO[2.2.2]OCTANE DERIVATIVES
Authors: Humber L. G. , Myers G. , Hawkins L. , Schmidt C. , Boulerice M.
Published: May 2006

Several routes to the synthesis of 1,4-disubstituted bicyclo[2.2.2]octanes have been explored and the syntheses of several such derivatives are reported. The 1,4-disubstituted bicyclo[2.2.2]-octane nucleus could not be prepared through an elimination reaction on a corresponding 2,5-disubstituted derivative or by the Diels–Alder reaction of various dienophiles with dimethyl 1,3-cyclohexadiene-1,4-dicarboxylate.Unusual products are obtained from the reaction of tetracyanoethylene with dimethyl terephthalate and with 1,3-cyclohexadienes containing electron-attracting groups in the 1,4-positions. Some spectral properties of these compounds are described.
THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: III. A GALACTOMANNAN FROM TRICHOPHYTON INTERDIGITALE
Authors: Blank F. , Perry M. B.
Published: May 2006

The water-soluble polysaccharide preparation from Trichophytoninterdigitale was fractionated to give two distinct galactomannans and a glucan. A galactomannan isolated via its insoluble copper complex had [α]D +75° (water) and was composed of D-galactose (12%) and D-mannose (88%). On periodate oxidation, the galactomannan consumed 1.73 mole periodate and released 0.67 mole formic acid and 0.12 mole formaldehyde per anhydrohexose unit. Hydrolysis of the methylated galactomannan gave 2,3,5,6-tetra-O-methyl-D-galactose (1 part), 2,3,4,6-tetra-O-methyl-D-mannose (1 part), 2,3,4-tri-O-methyl-D-mannose (4 parts), and3,4-di-O-methyl-D-mannose (2 parts). Mild acid hydrolysis of the galactomannan removed all the galactose residues, leaving a mannan having [α]D +84° (water) whose structure was analyzed by periodate oxidation and methylation techniques.
COMPLEX METAL HYDRIDE REDUCTION OF A KETIMINE AND A THIOKETONE
Authors: Sahyun M. R. V.
Published: May 2006

not available
PHOTOMETRIC OBSERVATIONS ON THE REACTIONS OF ACTIVE NITROGEN WITH CHLORINE AND BROMINE
Authors: Raxworthy K. S. , Phillips L. F.
Published: May 2006

not available
BIOSYNTHESIS OF ERGOT ALKALOIDS. THE ORIGIN OF THE N-METHYL GROUP
Authors: Baxter Ross M. , Kandel S. I. , Okany A. , Pyke R. G.
Published: May 2006

not available
SUPERSONIC MOLECULAR BEAMS: II. THEORY OF THE FORMATION OF SUPERSONIC MOLECULAR BEAMS
Authors: Valleau J. P. , Deckers J. M.
Published: May 2006

Supersonic molecular beams may be isolated from gas which has been allowed to expand through a nozzle. This paper concerns the kinetic theory of the isolation of such beams, taking into account the effect of collisions in the region between the skimmer and the collimator. These collisions turn out to be important. In particular, they offer an explanation of two interesting phenomena: (a) the existence of a maximum beam intensity as the distance is varied between the nozzle and the collimating system and (b), in a mixed beam, large increases in the intensity of the heavy gas as its initial concentration is reduced by replacement with a much lighter gas. The theory is compared with various experimental results. Although severe approximations have been introduced into the theory, it appears to predict the above phenomena in a way that is better than qualitative.
SECONDARY KINETIC ISOTOPE EFFECTS IN BIMOLECULAR NUCLEOPHILIC SUBSTITUTIONS: II. α-DEUTERIUM EFFECTS IN MENSCHUTKIN REACTIONS OF METHYL IODIDE
Authors: Leffek K. T. , MacLean J. W.
Published: May 2006

Secondary deuterium isotope effects have been measured for the reactions between methyl and methyl-d3 iodides and a series of tertiary amines in benzene solvent. Deuterium substitution increased the rate of each reaction but the rate ratios (kH/kD) show no systematic change with variation in the structure of the amine. The isotope effect for the reaction with 2-picoline was measured at different temperatures over a range of 40 deg and shows no change. These isotope effects may be rationalized as internal rotational effects of the methyl group or as solvation effects.
NUCLEAR MAGNETIC RESONANCE INVESTIGATIONS OF SOME GROUP V METAL FLUORIDES AND OXYIONS
Authors: Hatton J. V. , Saito Y. , Schneider W. G.
Published: May 2006

The nuclear magnetic resonances of 51V, 93Nb, 121Sb, 123Sb, and 181Ta in solutions of the pentafluorides of these elements were measured. All of these nuclei have large electric quadrupole moments. In most cases the chemical species observed was identified by spin-multiplet splitting of the metal resonance. In aqueous 48% HF solutions the 181Ta resonance could not be observed; the 121Sb and 123Sb resonances consist of a symmetrical septet, corresponding to the hexafluoride ion; the 93Nb resonance consists of a single exchange narrowed line; and the 5IV resonance consists of a symmetrical quintet, corresponding to the VOF4− ion. In alcohol solution NbF5 disproportionates to form NbF6−, whereas in ether and triethylamine solutions, the complexes NbF5•OEt2 and NbF6•NEt3 are formed. The latter complexes were confirmed by proton resonance measurements. Resonances of 5IV in aqueous solutions of V2O5 and of NH4VO3 as a function of pH show a parallel behavior and reveal the presence of six different oxyions of vanadium. Five of these resonances are assigned to the species, VO43−, VO3−, V2O74− V3O106− and VO2+, on the basis of the resonance line width and the pH range in which the resonance appears.
CORRELATIONS OF PROTON COUPLING CONSTANTS IN THE CYCLOPROPANE RING WITH ELECTRONEGATIVITY: CONSIDERATION OF THE PROTON RESONANCE SPECTRUM OF CYCLOPROPYLLITHIUM
Authors: Schaefer T. , Hruska F. , Kotowycz G.
Published: May 2006

The analysis of cyclopropyllithium allows estimates to be made of all proton coupling constants. The exceptionally small couplings across carbon atoms 2 and 3 are examined in the context of correlations of coupling constants with the electronegativities of substituents. It is concluded that, although the couplings involving protons attached to the same carbon as the substituent decrease with increasing electronegativity of the substituent, the opposite is true for couplings involving the protons attached to carbons one bond removed from the substituent. Individual values are suggested for the coupling constants in cyclopropane itself and these agree with the observedI3C side bands in its proton spectrum.
THE REACTIONS OF METHYLENE RADICALS WITH ACETALDEHYDE AND PROPIONALDEHYDE
Authors: Back M. H.
Published: May 2006

The reactions of methylene radicals with acetaldehyde and propionaldehyde have been studied over the temperature range 48–118 °C and over a range of pressures of aldehyde and carbon dioxide. From acetaldehyde, the main products were carbon monoxide, methane, ethane, and acetone, with small amounts of ethylene at low pressures of acetaldehyde. With carbon dioxide present, small amounts of propylene oxide were formed, but propionaldehyde was not observed. The main products from the reaction with propionaldehyde were carbon monoxide, methane, ethane, and ethylene, with small amounts of methyl ethyl ketone, butene oxide, and isobutyraldehyde. The relation of the results to the relative rates and mode of attack of methylene on the various bonds is discussed.
THE CHEMISTRY OF THE AMINOCHROMES: PART VI. THE REACTION OF ADRENOCHROME WITH GLUTATHIONE
Authors: Mattok G. L. , Heacock R. A.
Published: May 2006

The reaction between adrenochrome and glutathione has been studied. The main products result from the 1,4-addition of glutathione to the C5 unsaturated carbonyl systems in adrenochrome involving the C6—C7 and the C4—C9 double bonds, and are probably 7-S-glutathionyl-5,6-dihydroxy-N-methylindole and 9-S-glutathionyl-2,3,6,9-tetrahydro-3,5-dihydroxy-6-oxo-N-methylindole respectively. 5,6-Dihydroxy-N-methylindole is also formed during the interaction of glutathione and adrenochrome. The mechanisms by which these compounds are formed are discussed.
ESTER HYDRAZONES AS POSSIBLE PRECURSORS TO ALKOXYDIAZOALKANES: I. THE SYNTHESIS OF ESTER (p-TOLYLSULFONYL)HYDRAZONES AND THEIR DECOMPOSITION IN PROTIC SOLVENTS TO GIVE MIXED ACETALS
Authors: Crawford Robert J. , Raap Rintje
Published: May 2006

Methyl benzoate (p-tolylsulfonyl)hydrazone (I) was prepared from the reaction between (p-tolylsulfonyl)hydrazide and either methyl benzimidate hydrochloride or methyl orthobenzoate. When the potassium or sodium salt of this hydrazone was decomposed, thermally or photochemically, in the presence of alcohols, benzaldehyde mixed acetals could be isolated in good yields and of high purity. When the decomposition was carried out in the presence of piperidine, there was produced 1(α-methoxybenzyl) piperidine (II) and α,α-dipiperidinotoluene (III). The reaction products can be explained by assuming the initial formation of phenylmethoxydiazomethane.
A PULSED ION SOURCE FOR THE STUDY OF UNIMOLECULAR AND BIMOLECULAR REACTIONS OF GAS-PHASE IONS
Authors: Shannon T. W. , Meyer F. , Harrison A. G.
Published: May 2006

A pulsed ion source has been constructed for use with a magnetic-deflection mass spectrometer. With this source the time between ion formation and withdrawal for analysis can be controlled and varied in a known manner. The design and operating characteristics of the source are discussed and a technique is described for the measurement of ion withdrawal times using the pulsing technique. The rate constant for the ion molecule reaction[Formula: see text]has been determined for the reaction of thermal energy ions using reaction time as the experimental variable. The equivalent reactions in the deuteriomethanes have also been studied. Preliminary results obtained in the study of the unimolecular fragmentation of the cyclohexadiene, toluene, and spiroheptadiene parent ions are presented.
ELECTROCHEMICAL STUDIES ON TITANIUM IN MOLTEN LiCl–KCl EUTECTIC
Authors: Baboian R. , Hill D. L. , Bailey R. A.
Published: May 2006

The methods of potentiometry and polarography have been used to study the Ti(II) and Ti(III) ions in solution in the LiCl–KCl eutectic at 450 °C and 550 °C. Solutions of Ti(II) were prepared by anodic dissolution of Ti metal, and Ti(III) solutions by coulometric titration of Ti(II) by Pt(II). Apparent standard electrode potentials were measured for the Ti(II)/Ti and Ti(III)/Ti(II) couples against the Pt(II)/Pt and Ag(I)/Ag reference electrodes. Values obtained on the mole fraction scale with a Pt(II)/Pt reference electrode were[Formula: see text]Polarographic waves for oxidation and reduction of Ti(II), and for reduction of Ti(III), were observed.
AN ELECTRON IMPACT STUDY OF SOME C8HI0 ISOMERS
Authors: Meyer F. , Haynes P. , McLean Stewart , Harrison A. G.
Published: May 2006

The mass spectra of 1-, 2-, and 6-methylspiro[2.4]hepta-1,3-diene have been measured and found to be very similar to the spectra of 7-methylcycloheptatriene and the isomeric alkyl benzenes. It is concluded that in all cases the major part of the fragmentation occurs by identical paths involving identical intermediates. This conclusion is supported by deuterium labelling and appearance potential data. On the other hand the mass spectrum of 2,5-dimethyl-1,5-hexadien-3-yne, an acyclic C8H10 isomer, shows a number of significant differences in its fragmentation pattern. These differences are reflected in the energetics of ion formation and it is concluded that in this case the fragmentation proceeds through different intermediates.
MASS DISTRIBUTION IN THERMAL NEUTRON FISSION OF 239Pu
Authors: Marsden D. A. , Yaffe L.
Published: May 2006

Improved radiochemical techniques have been used to study the distribution in mass of the fission fragments resulting from thermal neutron fission in 239Pu.Disintegration rates and half-lives were determined by measurement with a 4πβ gas flow proportional counter. Further identification of the nuclides was obtained by gamma scintillation spectrometry. The flux intensity during irradiation was monitored by the 59Co(n,γ)60Co reaction.The absolute fission yields of 89Sr, 90Sr, 91Y, 95Zr, 99Mo, 103Ru, 106Ru, 105Rh, 109Pd, 1I2Pd, 111Ag, and 115Cd in the light mass peak and 127Sb, 131I, 133I, 132Te, 137Cs, 140Ba, 141Ce, 143Ce, 144Ce, 147Nd, and 156Eu in the heavy mass peak have been measured. In addition, the independent yields of 82Br, 124Sb, 126Sb, and 136Cs were obtained.
THERMAL INDOLIZATION OF ARYLHYDRAZONES
Authors: Kelly A. H. , McLeod D. H. , Parrick J.
Published: May 2006

Thermal cyclization of arylhydrazones in the absence of acid catalyst has been investigated. Indole was not obtained from acetaldehyde phenylhydrazone; aniline, N-ethylaniline, and an unidentified compound were isolated. Phenylhydrazones of cyclohexanone and cyclopentanone and their 2-substituted derivatives were cyclized, often in good yield, to the indole and indolenine; the nature of the substituent markedly influences the ratio of the two products. Gas–liquid chromatographic analysis of the reaction mixture from indolization of two arylhydrazones revealed no crossed products. Nitrophenylhydrazones do not cyclize in good yield, but thermal indolization of some pyridylhydrazones is a good method for the preparation of pyrrolopyridines.
THE OPTICAL ACTIVITY OF FUCOXANTHIN
Authors: Antia N. J.
Published: May 2006

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UREA INCLUSION COMPOUNDS OF ALKENOIC ACIDS AND ALKYL ALKENOATES
Authors: Radell Jack , Brodman B. W.
Published: May 2006

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THE PREPARATION OF THIOACETALS FROM ORTHOTHIOBORIC ESTERS
Authors: Bessette F. , Brault J. , Lalancette J. M.
Published: May 2006

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THE AMMONOMERCURATION OF CYCLOHEXENE
Authors: Chow D. , Robson J. H. , Wright George F
Published: May 2006

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HYDRATION OF PURINES, PYRIMIDINES, NUCLEOSIDES, AND NUCLEOTIDES
Authors: Falk Michael
Published: May 2006

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REACTIONS OF OZONIDES: III. OZONOLYSIS OF ETHYL 10-UNDECENOATE IN ETHANOL
Authors: Diaper D. G. M. , Mitchell D. L.
Published: May 2006

Diethyl sebacate was the major product obtained by ethanolysis of the ozonization products of ethyl 10-undecenoate in the temperature range 28 to 170 °C. Mixed esters of sebacic acid were similarly obtained, in poor to moderate yields, by alcoholysis of the ozonization product from an alkyl ester of 10-undecenoic acid in the appropriate alcohol. Sebacic acid half esters are prepared by a similar treatment of the ozonization products from 10-undecenoic acid itself. Ester formation has been shown to proceed mainly by rearrangement of an alkoxyhydroperoxide, with oxidative esterification of an aldehyde intermediate contributing to a minor degree.
STRUCTURAL STUDIES BY MASS SPECTROMETRY: DETERMINATION OF THE STRUCTURE OF LYCOFAWCINE (BASE L)
Authors: Ayer W. A. , Bowman W. R. , Kebarle P. , Burnell R. H.
Published: May 2006

The mass spectra of lycofawcine (base L from L. fawcettii) and some of its derivatives are recorded and discussed. On the basis of the interpretation of the mass spectra a structure (IV) is proposed for lycofawcine. Experiments which confirm structure IV are described, and the stereochemistry of lycofawcine is discussed.
ESTER HYDRAZONES AS POSSIBLE PRECURSORS TO ALKOXYDIAZOALKANES: II. THE DECOMPOSITION OF ESTER (p-TOLYLSULFONYL) HYDRAZONE SALTS IN APROTIC SOLVENTS
Authors: Crawford Robert J. , Raap Rintje
Published: May 2006

The thermal and photochemical decomposition of methyl benzoate (p-tolylsulfonyl)hydrazone salts in 1,2-dimethoxyethane, 1,2-diethoxyethane, or diglyme gives rise to benzaldehyde dimethyl acetal, methyl benzoate azine (II), meso-1,2-diphenyl-1,2-dimethoxyethane, and methyl α-(p-tolylsulfonyl)benzyl ether. The thermal decomposition in the presence of diethyl fumarate produced diethyl 3-methoxy-3-phenyl-trans-1,2-cyclopropanedicarboxylate (XIV) in 62% yield; a low yield (4%) of the two isomeric forms of 1-methoxy-2-n-octyl-1-phenyl-cyclopropane (V) was formed in 1-decene. The thermal and photochemical decomposition of potassium 4-pentenyl benzoate (p-tolylsulfonyl)hydrazone (XVIII) produced 1-phenyl-2-oxabicyclo[4.1.0]heptane (XXI) in 14 and 21% yield respectively. These products provide additional evidence for the occurrence of alkoxydiazoalkanes and suggest alkoxycarbenes as possible intermediates in the decomposition of ester (p-tolylsulfonyl)hydrazone salts.
THE RADIOLYSIS OF ETHANOL: III. LIQUID PHASE
Authors: Myron J. J. J. , Freeman G. R.
Published: May 2006

The G values of the major products of the γ-radiolysis of liquid ethanol at a dose of 2 × 1020 eV/g are: hydrogen, 4.2; acetaldehyde, 1.9; 2,3-butanedio1, 2.2; G(—C2H5OH) = 7.5. At progressively lower doses G(H2) increases to a maximum of 5.0. The yield of water, G(H2O) = 0.5, is equal to the sum of the yields of the C2 fragments found in the other products.The approximate yields of three kinetically distinguishable sources of hydrogen were found to be [Formula: see text] G(H2) = 2.7 and G(unscavengeable H2) = 1.5. The half-life of solvated electrons with respect to reactions such as[Formula: see text]is 3 μs.Both 1,3-pentadiene and benzene inhibit hydrogen and glycol formation but neither affect the high dose yield of acetaldehyde. Pentadiene reacts with H atoms and other radicals and possibly also with [Formula: see text] Benzene appears to inhibit hydrogen and glycol formation mainly by an unidentified activation transfer process.
CONSTITUTION OF AN ARABINOGALACTOMANNAN FROM HONEY
Authors: Siddiqui I. R.
Published: May 2006

An arabinogalactomannan isolated from honey consisted of D-mannose, L-arabinose, and D-galactose in molar proportions of 1.0:2.04:4.04 respectively. Electrophoretic and sedimentation results indicated that the arabinogalactomannan was homogeneous. Methylation studies showed a highly branched structure. Hydrolysis of the methylated polysaccharide gave 2,3,4,6-tetra-O-methyl-D-mannose (3 molecular proportions); 2,3,4,6-tetra-O-methyl-D-galactose (2 molecular proportions); 2,3,5-tri-O-methyl-L-arabinose (1 molecular proportion); 2,3,4-tri-O-methyl-D-galactose (6 molecular proportions); 2,3-di-O-methyl-L-arabinose (4 molecular proportions); 2,5-di-O-methyl-L-arabinose (1 molecular proportion); 2,4-di-O-methyl-D-galactose (5 molecular proportions). The general structural features of the arabinogalactomannan are discussed.
ADDITION COMPOUNDS OF TITANIUM(IV) CHLORIDE CONTAINING ELEMENTS OF GROUPS V AND VI AS DONOR ATOMS
Authors: Westland Alan D. , Westland Lieselotte
Published: May 2006

Complexes TiCl4. L where L is a mono- or bi-dendate ligand having P, As, S, or Se as donor atom were prepared. Triphenylphosphine and dialkyl sulfide also form complexes TiCl4.2L. Far infrared data are presented for certain of the complexes.
REACTIONS OF PALLADIUM COMPOUNDS WITH ACETYLENES: II. TETRAKIS(p-CHLOROPHENYL)CYCLOBUTADIENE PALLADIUM COMPLEXES
Authors: Maitlis P. M. , Pollock D. , Games M. L. , Pryde W. J.
Published: May 2006

It is found that both diphenylacetylene and bis(p-chlorophenyl)acetylene on reaction with bis(benzonitrile)palladium chloride in benzene give the benzenoid trimer (R6C6) as well as a new type of cyclobutadiene complex [(R4C4)(PdCl2)x]2(R = Ph and p-ClC6H4) for which structure IV is proposed. p,p′-Dichlorotolan reacts with bis(benzonitrile)palladium chloride in ethanol – methylene chloride to give a complex [(R4C4OC2H5)PdCl]2 (II) which is converted into the normal cyclobutadiene complex [(R4C4)PdBr2]2 (V) on treatment with hydrogen bromide. This can also be obtained from IV. The tetrakis(p-chlorophenyl)cyclobutadiene palladium halides on treatment with tri-n-butylphosphine give a dimer of tetrakis(p-chloro-phenyl)cyclobutadiene which is probably octakis(p-chlorophenyl)cyclooctatetraene. Tetrakis-(p-chlorophenyl)cyclobutadiene iron tricarbonyl has also been prepared from IV and V by a ligand-transfer reaction.
13C N.M.R. STUDIES: PART IV. CARBON-13 N.M.R. SPECTRA OF SOME ALKYL PHENYL KETONES
Authors: Dhami K. S. , Stothers J. B.
Published: May 2006

The 15.1 Mc/s 13C n.m.r. spectra of 21 substituted alkyl phenyl ketones, ArCOR, have been determined and the 13C chemical shifts measured. This group of compounds included examples of each of the ethyl, isopropyl, and t-butyl phenyl ketone series. Variations of the chemical shifts with structure are analyzed and compared with the results for substituted acetophenones. The study of steric inhibition of conjugation in these compounds by means of their 13C data is discussed in detail. The parameters for the acetyl carbons for a few methyl aryl ketones have been determined as well to examine the effect of orientation of this group on a polycyclic aromatic skeleton.
CONTRIBUTION A L'ÉTUDE DU MÉCANISME D'OXYDATION CHROMIQUE DES ALCOOLS SECONDAIRES
Authors: Richer Jean-Claude , Gilardeau Claude
Published: May 2006

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SOLVOLYSIS OF ALKYL CHLOROSULFATES: PART I. REACTION OF n-PROPYL CHLOROSULFATE WITH NUCLEOPHILES
Authors: Buncel E. , Millington J. P.
Published: May 2006

The effect of various reagents on the rate of hydrolysis of n-propyl chlorosulfate in 10 M aqueous dioxane is reported. Halide ions increase the rate of reaction (I− > Br− > Cl−) but perchlorate is without effect. Hydroxide and pyrrolidine have a strong accelerating effect, but only at higher concentrations. These observations support a bimolecular mechanism: rate-determining displacement by nucleophile on carbon, with OSO2Cl− as the leaving group. The present results are not in accord with a previous proposal that alkyl chlorosulfates react by rate-determining sulfur–chlorine bond fission followed by fast displacement by nucleophile on carbon.
SPECTROSCOPIC STUDIES OF ORGANOPHOSPHORUS COMPOUNDS: PART I. THE CONSTITUTION OF ALKYLPHOSPHINE – CARBON DISULFIDE ADDUCTS
Authors: Beg M. Arshad A. , Siddiqui M. S.
Published: May 2006

The constitution of the alkylphosphine – carbon disulfide adducts has been investigated by the study of their infrared spectra. Certain definite features of the spectra of the adducts are the shift of the P—C asymmetric vibrations to higher frequencies and the large shifts in the fundamentals of the acceptor molecule. These features are attributed to the formation of a quadruply connected phosphorus compound. From a comparison of the spectra of the carbon disulfide adducts with those of the corresponding phosphonium compounds, phosphine oxides and phosphines, evidence is provided for the structure of these compounds which has been suggested to be of the phosphonium type.
A QUANTUM-THEORETICAL STUDY OF SOME AROMATIC NITRILES BY THE SEMIEMPIRICAL LCAO–SCF–MO METHOD
Authors: Popkie H. E. , Moffat J. B.
Published: May 2006

Semiempirical LCAO–SCF–MO calculations have been carried out on some aromatic nitriles in an attempt to predict spectral transitions. Mataga's approximation has been applied to the Coulomb repulsion integrals and a set of parameter values which gives a reasonable prediction of the observed singlet–singlet transition energies of pyridine and benzonitrile was used. The calculations were applied to pyridine, benzonitrile, 2-, 3-, and 4-cyanopyridine, 1,2-, 1,3-, and 1,4-dicyanobenzene, 2,6-dicyanopyridine, and 1,2,4,5-tetra cyanobenzene. Computed singlet–singlet transition energies are in fair agreement with experiment. However, calculated singlet–triplet transition energies are, in general, lower than the experimental values by about 1 eV. The SCF ground state MO's and orbital energies are reported together with the wave functions for the four lowest-energy excited singlet states for each molecule.
REACTIONS OF THE ETHYL RADICAL: V ADDITION TO THE MONOMETHYL ACRYLONITRILES
Authors: James D. G. L. , Ogawa Takeshi
Published: May 2006

The Arrhenius parameters have been measured for the addition of the ethyl radical to methacrylonitrile and to the cis and trans isomers of crotononitrile. The energy of activation for each of these derivatives is significantly greater than for acrylonitrile. There is no significant variation among the values of the energy of activation for the monomethyl acrylonitriles, so that the introduction of a methyl group into the acrylonitrile molecule appears to raise the energy of activation by an amount which is insensitive to the position of the group. The pre-exponential factor is significantly smaller for each of the crotononitrile isomers than for methacrylonitrile; the partial shielding of the β-carbon atom of crotononitrile is thus expressed by a steric factor rather than by an energy term. The cis-trans isomerization of crotononitrile is photosensitized by diethyl ketone illuminated by o 3 130 Å radiation in both the liquid and gaseous phases; a mechanism of triplet state energy transfer is proposed for the process.
FAST REARRANGEMENT OF exo-NORBORNANOL IN STRONG ACID SOLUTIONS
Authors: Fraenkel Gideon , Ralph Phillip D. , Kim John P.
Published: May 2006

Nuclear magnetic resonance spectra have been obtained at several temperatures for solutions of 2-exo-norbornanol in strong acids. The spectra change with temperature reversibly. It is concluded that the 2-exo-norbornanol undergoes very rapid rearrangement, the fast steps being 2,6 and 3,2 hydride shifts, respectively.
ISOMERIC 1,3-CYCLOPENTANEDICARBOXYLIC ACIDS FROM THE OXIDATIVE OZONIZATION OF NORBORNENE
Authors: Temin Samuel C. , Baum Melvin E.
Published: May 2006

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SUR LES PRODUITS DE SUBSTITUTION DU DIMÉTHOXY-1,7 NAPHTALÈNE
Authors: Richer Jean-Claude , Lamarre Claude
Published: May 2006

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PHOTOCHEMICAL SYNTHESIS OF VINYLTHIOLS
Authors: Strausz O. P. , Hikida T. , Gunning H. E.
Published: May 2006

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AROMATIC SUBSTITUTION: PART VIII. SOME ASPECTS OF THE MECHANISM OF THE TSCHITSCHIBABIN REACTION
Authors: Abramovitch R. A. , Helmer F. , Saha J. G.
Published: May 2006

The mechanism of the direct amination of pyridines is discussed in terms of both addition–elimination and elimination–addition pathways. The absence of deuterium kinetic isotope effects as well as the orientations observed in such reactions rule out the intervention of 2,3- or 2,6-dehydropyridines. The effect of a 3-methyl group upon the reactivities towards the amide ion of the various nuclear positions in pyridine has been determined. Predictions based on molecular orbital (m.o.) calculations are discussed in terms of the detailed mechanism of this reaction and of the orientations observed.
THE ORTON REARRANGEMENT IN APROTIC SOLVENTS: PART II. THE ACID-CATALYZED BROMINATION OF ANISOLE BY A SERIES OF 4-SUBSTITUTED N-BROMOACYLANILIDES
Authors: Scott John M. W. , Martin June G.
Published: May 2006

Anisole has been brominated using a sequence of brominating reagents generated by the reaction of a series of 4-substituted N-bromoacylanilides 4-RC6H4NBrAc (R = Ph, H, Cl, and NO2) with a series of carboxylic acids R′COOH (R′ = CF3, CCl3, CH2Cl, and CH3). The isomer distributions of the bromoanisoles produced have been measured for each N-bromoacylanilide–carboxylic acid pair and their variation with both the structure of the N-bromoacylanilide and the carboxylic acid provides a useful basis for a discussion of the mechanism of the bromine migration.
α-PYRIDONE COMPLEXES AND THEIR INFRARED SPECTRA
Authors: Cook Denys
Published: May 2006

The infrared spectra of complexes of 1-methyl-2-pyridone and 1-methyl-2-quinolone with Lewis acids are consistent with interaction at the carbonyl group. The stretching frequency of this group, vco, is lowered on complex formation, the change being proportional to the Lewis acidity. Two other bands, at 1 670 and 1 380 cm−1 move to lower frequency in much smaller steps and are associated with ring modes.