bluuebunny/crossref_metadata_2025 huggingface dataset:
SYNTHESIS OF SOME ALKYLATED ADENINES AS POTENTIAL ANTIMETABOLITES
Authors: Abshire C. J. , Berlinguet L.
Published: May 2006

Several substituted adenines and (or) their salts have been prepared by condensing adenine in dimethylformamide with the following halides: benzyl chloride, p-methylbenzyl chloride, n-propyl bromide, (3-chloropropyl) benzene, α-bromo-γ-butyrolactone, allyl bromide, and cinnamyl chloride. The reaction may be carried out in large quantities and the salts were isolated in high yields.Characterization of these compounds indicated that they are pure 3-substituted adenines with the possible exception of the allyl and the n-propyl derivatives, which may contain little, if any, of the 7- or 9-isomers.
REACTIONS OF PHENYL-SUBSTITUTED HETEROCYCLIC COMPOUNDS: V. NITRATIONS OF 1,3- AND 1,5-DIPHENYLPYRAZOLES
Authors: Lynch Brian M. , Hung Yuic-Yung
Published: May 2006

Dinitration of 1,3- or 1,5-diphenylpyrazole in sulphuric acid yields the corresponding di(p-nitrophenyl) compounds, while nitric acid–acetic anhydride yields the 4-nitro-1-p-nitrophenyl compounds.Mononitration at the 4-position occurs when the diphenylpyrazoles and several other 1-phenylpyrazoles are nitrated at 0° by nitric acid–acetic anhydride.Possible explanations of the dependence of orientation on the nature of the nitrating agent-are discussed.Nuclear magnetic resonance (n.m.r.) spectroscopy was used in demonstrating the structures of many of the nitration products, and a general discussion of the n.m.r. spectra of substituted 1-phenylpyrazoles is given.
NEW REARRANGEMENTS OF THE CARYOPHYLLENE SKELETON: THE DINITROPHENYLHYDRAZONES FROM CARYOPHYLLENE OXIDE
Authors: Warnhoff E. W.
Published: May 2006

Caryophyllene oxide (I) and dihydrocaryophyllene oxide (II) have been found to give 2,4-dinitrophenylhydrazones. Structures IV, V, and VII are assigned to three of these compounds on the basis of nuclear magnetic resonance data, other spectral and chemical data, and mechanistic considerations. Structure VII is the product of a new cyclization–rearrangement of the caryophyllene system. The dinitrophenylhydrazone previously obtained from isocaryophyllene oxide-a (III) is probably identical with VII. Three other new derivatives of caryophyllene are described, one of which (VI) is an intermediate in the conversion of I to VII.
RELATIVE RATES OF BASE-CATALYZED EXCHANGE OF ALPHA- AND GAMMA-HYDROGEN IN AN α,β-UNSATURATED KETONE
Authors: Warkentin J. , Lam L. K. M.
Published: May 2006

Relative rates of base-catalyzed exchange of vinylic and allylic hydrogen, in an α,β-unsaturated ketone, have been determined. In refluxing heavy water, with OD− catalyst, vinyl hydrogen was exchanged about 170 times as rapidly as allyl hydrogen. In CD3OD containing CD3O− the two rates were equal or nearly equal at ambient temperature. Factors which may contribute to the observed difference between the relative rates are discussed and results of simple molecular orbital calculations are presented.
POLYSACCHARIDES FROM THE SEEDS OF THE HUACRA PONA PALM (IRIARTEA VENTRICOSA)
Authors: Sowa W. , Jones J. K. N.
Published: May 2006

not available
THE REACTION OF SULPHUR TETRAFLUORIDE WITH SOME NITROGEN COMPOUNDS
Authors: Marinier B. , Boivin Jean L.
Published: May 2006

not available
THE ALKALOIDS OF ASPIDOSPERMA OBLONGUM A.D.C.
Authors: Palmer K. H.
Published: May 2006

not available
STUDIES ON THE THERMODYNAMICS AND CONDUCTANCES OF MOLTEN SALTS AND THEIR MIXTURES: PART III. DENSITIES, MOLAR VOLUMES, VISCOSITIES, AND SURFACE TENSIONS OF MOLTEN LITHIUM CHLORATE, WITH SMALL ADDITIONS OF WATER, AND OTHER SUBSTANCES
Authors: Campbell A. N. , Williams D. F.
Published: May 2006

The density (2.088 g ce−1) at 131.8 °C and viscosity (0.35 P at 131.8 °C) and their temperature dependence, of molten lithium chlorate, have been determined. Similar results have been obtained for lithium chlorate melts containing small quantities of water. The surface tension and its temperature dependence have been determined for lithium chlorate and for several lithium chlorate – water and lithium chlorate – lithium nitrate mixtures. From these measurements the surface heat has been calculated.The results for pure lithium chlorate indicate that the melt is complex, this complexity probably caused by association of some kind. This is especially evident just above the melting point, since there the temperature change in properties is greatest.Addition of water to the lithium chlorate melt causes the melt properties, especially the viscosity, to alter considerably. These changes are in part caused by a breakdown of the structural entities in the melt.
KINETICS AND MECHANISMS OF THE THERMAL DECOMPOSITION OF ACETALDEHYDE: II. THE REACTION IN THE PRESENCE OF NITRIC OXIDE
Authors: Eusuf M. , Laidler K. J.
Published: May 2006

The decomposition of acetaldehyde has been reinvestigated in the presence of various amounts of nitric oxide, over a range of temperatures (495 to 525 °C) and acetaldehyde pressures (36 to 340 mm Hg). At higher acetaldehyde pressures there is no inhibition, the rate steadily increasing with increasing nitric oxide concentration; at low acetaldehyde concentrations increasing amounts of nitric oxide first give inhibition and then give catalysis. The degree of inhibition increases with decrease in temperature. As the nitric oxide concentration is increased, the order rises above 3/2 and then falls to 3/2 again. At higher nitric oxide concentrations the rate varies with [CH3CHO]3/2 [NO]1/2. All of the facts are explained by a mechanism according to which initiation occurs by[Formula: see text]together with the processes occurring in the absence of nitric oxide (cf. Part I). Termination is considered to involve the reaction occurring in the case of no inhibition (CH3 + CH3 + X → C2H6 + X) together with[Formula: see text][Formula: see text]Application of the mechanism to the results is discussed in detail.
THE SYNTHESIS OF SOME DERIVATIVES OF 3,4-METHYLENEDIOXYBENZENE
Authors: Singh Pritam , Berlinguet Louis
Published: May 2006

A few derivatives of 3,4-methylenedioxy-α-nitromethylbenzyl alcohol (I) have been prepared. Chlorination with hydrochloric acid and potassium chlorate gave 6-chloro-3,4-methylenedioxy-α-nitromethylbenzyl alcohol (II) which on refluxing with acetic anhydride and sodium acetate gave 6-chloro-3,4-methylenedioxy-ω-nitrostyrene (III). Attempted reduction of (I) with ammonium formate resulted in dehydration to give 3,4-methylenedioxy-ω-nitrostyrene (IV). Reduction of (I) with hydrazine hydrate gave an isobenzaldoxime (VI).β-(3,4-Methylenedioxyphenyl) serine (VII) was prepared by the condensation of piperonal with glycine. α,β-Dibromo-β-(3,4-methylenedioxyphenyl) propionic acid could not be aminated by a dilute aqueous solution of ethylamine. Decarboxylation and elimination of HBr took place to give ω-bromo-3,4-methylenedioxystyrene (VIII).
RÉACTION DU SULFURE DE BORE AVEC QUELQUES GROUPES CARBONYLES
Authors: Jerumanis S. , Lalancette J. M.
Published: May 2006

The reactions of boron sulphide with some types of carbonyls have been studied. The reaction of boron sulphide with aromatic aldehydes and aliphatic aldehydes which have been deprived of active hydrogen in the α position gives a good yield of the corresponding trithioaldehydes. This reaction is examined for four aldehydes, namely, benzaldehyde, 3-methylbenzaldehyde, 3-nitrobenzaldehyde, and 2,2′-dimethylpropionaldehyde. Through this study the authors have brought out a method which enables either the α-trithiobenzaldehyde, m.p. 166–167 °C, or the β-trithiobenzaldehyde, m.p. 225–226 °C, to be obtained selectively. The reaction of 3-methylbenzaldehyde with boron sulphide yields only one β stereoisomer, but nitrobenzaldehyde remains completely inert. The aldehydes having one active hydrogen in the α position undergo a dehydrogenation at the same time as the oxygen is being replaced by one atom of sulphur. 2,2′-Dimethylthiopropanal exists in a trimeric state at normal temperatures and becomes monomeric at higher temperatures, whereas the trithiobenzaldehydes do not depolymerize. Methyl benzoate reacts with boron sulphide to give tetraphenyldioxadiene. The structure of this extremely inert substance has been established mainly by physical means: infrared, ultraviolet, and n.m.r. spectra. The reaction of benzophenone and acetophenone with boron sulphide has been investigated. The former has been found inert to the action of the sulphide, and the latter reacts quite readily to give 2,4-diphenylthiophene. The structure of this thiophene is established by desulphuration over nickel. The role of boron sulphide as dehydrogenating and deoxygenating agent is discussed, and a laboratory preparation of boron sulphide is described.
FURTHER EVIDENCE FOR THE DIENONE-IMINE INTERMEDIATE IN THE FISCHER INDOLE SYNTHESIS: AN UNCATALYZED FISCHER REACTION UNDER MILD CONDITIONS
Authors: Robinson F. P. , Brown R. K.
Published: May 2006

Evidence has been presented for the transient formation of a dienone-imine intermediate in the Fischer indole synthesis analogous to the dienone intermediate found in the Claisen rearrangement. The isolation of methylamine hydrochloride, 8-chloro-1,2,3,4-tetrahydrocarbazole, and 5-amino-6-chloro-9-methyl-1,2,3,4-tetrahydrocarbazole from the room temperature, uncatalyzed condensation between cyclohexanone and N′-methyl-2,6-dichlorophenylhydrazine under enamine synthesis conditions can be rationalized only on the assumption of the occurrence of a dienone-imine intermediate. An example of a facile, uncatalyzed Fischer cyclization at room temperature has been described.
A THEORETICAL STUDY OF RING CLOSURE: APPLICATION TO THE CYCLIC–LINEAR DISTRIBUTION IN POLYDIMETHYLSILOXANE
Authors: Carmichael J. B. , Kinsinger J. B.
Published: May 2006

The purpose of this work was to provide insight into the formation of cyclics from fundamental considerations of chain geometry. The structural variables which must be specified are the length(s) of the valence bond in the skeletal structure, bond angle(s) in the skeletal structure, and the energetics and positions of the allowed conformations in the system. A mathematical model involving only these structural variables has been developed which is valid for chains with any number of bonds.This model is applied to the polydimethylsiloxane system in which cyclic molecules containing from six to eighteen atoms in their skeletal structures make up approximately 12 to 20% by weight of the equilibrated system. A three-rotational-state model is assumed for the polydimethylsiloxane chain. The relationship between cyclic formation and other features of polymer behavior and structure will be interpreted in terms of the model. A good correlation is shown between the experimental equilibrium constant for octamethylcylcotetrasiloxane and the theoretical equilibrium constant from the model calculation.
PROPYLENE GAS HYDRATE STABILITY
Authors: Clarke E. C. , Ford R. W. , Glew D. N.
Published: May 2006

not available
THE FORMATION OF TRIBUTYLIODOAMMONIUM IODIDE IN THE URANYL PHOTOSENSITIZED REACTION WITH TETRABUTYLAMMONIUM IODIDE
Authors: Wan J. K. S. , Schuck E. A. , Foote J. K. , Pitts Jr. J. N.
Published: May 2006

not available
PRIMARY PROCESS STUDIES BY MONOISOTOPIC PHOTOSENSITIZATION ON THE REACTIONS OF Hg 6(3P1) ATOMS WITH ALKYL CHLORIDES
Authors: Wan J. K. S. , Strausz O. P. , Allen W. F. , Gunning H. E.
Published: May 2006

The specific nature of the primary process in the reaction of 202Hg 6(3P1) atoms, photoexcited in natural mercury vapor by a cool 202Hg electrodeless discharge source, with CH3Cl has been examined in detail. Primary C–Cl bond scission occurs with unit efficiency. Quantum yields (φ) for the two primary modes of decomposition[Formula: see text]were found to have values of 0.71 (b) and 0.29 (a). The effect of various reaction parameters on the 202Hg enrichment in the calomel product has been investigated and the importance of isotopic mercury depletion in the reaction zone demonstrated by the use of intermittent illumination.A brief study of the reaction of ethyl, n-propyl, i-propyl, t-butyl, and n-amyl chlorides has revealed a relation between the molecular structure of the alleyl chloride and the efficiency of the monoisotopic route (a) to calomel formation. Thus, while the reactions of all the normal alkyl chlorides have φa values between 0.29 and 0.32, φa (isopropyl chloride) is only 0.22 and φa (t-butyl chloride) is 0.17.
SUR LES ÉTHERS ÉNOLIQUES DÉRIVÉS DU FORMYL-3 CAMPHRE
Authors: Richer Jean-Claude , Clarke Reginald
Published: May 2006

not available
OBSERVATIONS BY X-RAY DIFFRACTION ON DISCOLORED ZINC OXIDE AFTER HEATING
Authors: Secco E. A.
Published: May 2006

not available
THE REACTION OF DL-PROPYLENIMINE WITH MESO-1,2;3,4-DIEPOXYBUTANE
Authors: Holton Sandra L. , Christensen James E. , Crews Osborne P. , Goodman Leon
Published: May 2006

not available
PHOTOCHEMICAL TRANSFORMATIONS OF DIENES: II. THE PHOTOLYSIS OF 3-METHYLCHOLESTA-3,5-DIENE (V)
Authors: Just G. , Tullio V. Di
Published: May 2006

Photolysis of 3-methylcholesta-3,5-diene (V) in ethanol gave 3-methylenecholest-5-ene (VI), 6β-ethoxy-3α-methyl-3β,5-cyclo-5β-cholestane (VII), 3β-ethoxy-3α-methylcholest-5-ene (VIII), and 3α-methylcholesterol (VIIIa) as well as a number of unidentified hydrocarbons and alcohols. A similar photolysis in pentane, followed by reaction of the resulting 3β,5;4α,6α-bicyclo-5β-cholestane (IIa) with ethanol, gave the cyclo ether VII as the only isolable product.
COMPLEXES DU GERMANIUM (IV) AVEC LA DICHLORO-2,5 DIHYDROXY-3,6 p-BENZOQUINONE
Authors: Beauchamp A. , Benoit R. L.
Published: May 2006

not available
MEASUREMENT OF ELECTRON SPIN RESONANCE DIFFERENCE SPECTRA AT 77 °K: APPLICATIONS OF THE METHOD IN LOW-TEMPERATURE RADIATION CHEMISTRY
Authors: Smith D. R. , Pieroni J. J.
Published: May 2006

The technique of measuring e.s.r. difference spectra has been extended to 77 °K. This enables elimination of the main signal due to irradiated silica sample tubes and of about 90% of the hydrogen atom signal from the same source. Under certain conditions, e.g. when the e.s.r. spectrum due to one species can be photochemically bleached, the method permits resolution of two superimposed spectra. This has been demonstrated by measurements which resolve the e.s.r. singlet due to trapped electrons in irradiated tetrahydro-2-methylfuran from the underlying septet. These developments have rendered the e.s.r. difference method very useful for the study of paramagnetic species formed in systems which have been γ-irradiated at 77 °K.
THE REDISTRIBUTION REACTION OF BIS-MERCURIALS
Authors: French W. E. , Inamoto N. , Wright George F
Published: May 2006

The demetalation of diorganosubstituted mercury compounds is catalyzed by peroxides. When organomercuric salts are present this demetalation leads to formation of mercurous salt plus mercury. This latter combination has been found to be a catalyst for the redistribution reaction of bis-mercurials. It is suggested that all previously reported catalysts for this reaction operate by formation of the mercurous salt – mercury combination. Equilibration studies with this combination as catalyst indicate that random exchange is not general for the redistribution reaction of mercury compounds.
PRÉPARATION DU tert-BUTYL-5 DIMETHYL-3,3 CYCLOHEXÈNE ET DE QUELQUES ISOMÈRES
Authors: Richer Jean-Claude , Bélanger Patrice
Published: May 2006

not available
KINETIC STUDIES OF THE AgO/Ag2O ELECTRODE IN ALKALINE SOLUTIONS
Authors: Barradas R. G. , Fraser G. H.
Published: May 2006

The anodic oxidation of Ag2O to AgO in normal aqueous potassium hydroxide solution was investigated quantitatively under both galvanostatic and potentiostatic conditions at 25 °C. A few results for similar experiments in N/40 KOH are also reported. Tafel slopes and other parameters were determined. The experimental results show the dependence of current density as a hyperbolic function of overpotential, i.e. i = 2i0 sinh (λFη/2RT). The electron number λ was found to be 2 and the symmetry factor β was confirmed to be 1/2. It is proposed that the rate-determining step for the formation of AgO from Ag2O occurs at the Ag2O/AgO interface and involves the transfer of O−2 ions.
A UNIFIED TREATMENT OF INTEGRALS FOR ONE-ELECTRON OPERATORS
Authors: Fraga Serafin
Published: May 2006

A general formula has been developed to express, in terms of C-functions, the integrals appearing in the evaluation (when using Slater-type orbitals) of the expectation values of the most important one-electron operators.
REGULARITIES IN THE INFRARED SPECTRA OF 4-PICOLINE COMPLEXES
Authors: Cook Denys
Published: May 2006

Complexes of 4-picoline with Lewis acids have been prepared and their infrared spectra from 4 000 to 650 cm−1 recorded. Regular trends in certain absorption bands in the aromatic molecule, particularly those due to vibrations of the CC and CN bonds, are similar to those in pyridine complexes.
19F N.M.R. SPECTRA OF HEPTAVALENT FLUORIDES AND OXIDE PENTAFLUORIDES
Authors: Bartlett N. , Beaton S. , Reeves L. W. , Wells E. J.
Published: May 2006

The 19F n.m.r. spectra of IF7, ReF7, IOF5, ReOF5, and OsOF5 have been recorded. IF7gives rise to a broad symmetric doublet with a splitting of 4 100 ± 300 c.p.s. interpreted as partially collapsed and unresolved 19F—127I coupling. ReF7 gives a single line of width 60 c.p.s. at low field. These spectra give no information about the molecular structure other than that there is a fast intramolecular process causing magnetic equivalence. IOF5 and ReOF5 both exhibit a quintet/doublet spectrum indicative of locked C4v symmetry. The multiplet splittings in IOF5 are not resolved in pure IOF5 or in IOF5/IF7 mixtures, but can be seen for IOF5 in solution in IF5. The doublet lies to higher field than the quintet in IOF5, but the reverse occurs in ReOF5. In the paramagnetic molecule OsOF5 only the resonance of the unique axial fluorine is observed, indicative of localization of the non-bonding d-electron in the equitorial plane of the molecule.
THE PRINCIPAL CONFORMATIONS OF SOME ORTHO-SUBSTITUTED DIPHENYL ETHERS
Authors: Chandler W. D. , Smith W. MacFarlane , Moir R. Y.
Published: May 2006

A study of the nuclear magnetic resonance, infrared, and ultraviolet spectra showed that some doubly and triply ortho-substituted diphenyl ethers adopt, principally but not exclusively, the "H-inside" conformation, while the quadruply ortho-substituted 7-(4′-carbomethoxy-2′,6′-dinitrophenoxy)metameconine (V) adopts the "methoxy-inside"conformation. Interconversion of conformational isomers is extremely fast. Reduction of methyl 4-methoxy-3-nitrobenzoate with tin and hydrochloric acid gave methyl 3-amino-2-chloro-4-methoxybenzoate.
ULTRAVIOLET ABSORPTION OF SUBSTITUTED PHENYL AND POLYCYCLIC ARYL CHALCONES
Authors: Wheeler Owen H. , Gore Peter H. , Santiago Marcelina , Baez Rosita
Published: May 2006

The ultraviolet and near-visible light absorption of a number of substituted trans-chalcones are reported.
SOME CONSIDERATIONS ON THE STRUCTURE AND RADIATION CHEMISTRY OF WATER
Authors: Schiller Robert , Kiss István
Published: May 2006

The variation in the yields of products from the radiolysis of water at high solute concentrations and with increasing temperature are as yet unexplained by the diffusion theory. It is shown that by considering some structural features of water, both the temperature dependence of the yields and the concentration dependence of H2 production in the entire range of solute concentration can be interpreted. The results predicted from the relations thus established agree within an order of magnitude with the measured temperature coefficients of the yields.
SPECTRES ÉLECTRONIQUES DU FLUORANTHÈNE ET DE L'ACÉNAPHTYLÈNE EN SOLUTION A BASSE TEMPÉRATURE
Authors: Pesteil L. , Pesteil P. , Laurent F.
Published: May 2006

not available
TRACER DIFFUSION OF THALLIUM IN THALLIUM AMALGAMS
Authors: Foley William T. , Liu Michael T. H.
Published: May 2006

The tracer diffusion coefficient of thallium in thallium amalgams was measured at 25 °C by the capillary-reservoir technique. The values of 105D in cm2 s−1 at 0.0075, 0.0713, 0.1610, 0.2004, 0.2858, 0.3460, 0.3868, 0.4158 mole fraction thallium were 0.98, 0.85, 0.71, 0.62, 0.47, 0.41, 0.38, 0.39 with an average standard deviation of 0.016 × 10−5 cm2 s−1. The compound Tl2Hg5 plays a significant role in the tracer diffusion.
THE THERMAL REVERSIBILITY OF THE MICHAEL REACTION: IV. THIOL ADDUCTS
Authors: Allen C. F. H. , Fournier J. O. , Humphlett W. J.
Published: May 2006

The hydrochlorides of 27 Michael adducts, formed from alkylthiols and chalcones mono-substituted successively in each ring by nitro, chloro, and methoxy groups, were thermally cleaved by hot water. The amount of cleavage was readily determined iodimetrically.
CORROBORATION THAT 3,3′-DIINDOLYL SULPHIDE IS THE COMPOUND OBTAINED FROM THE REACTION OF INDOLE MAGNESIUM BROMIDE WITH SULPHUR
Authors: Jardine R. V. , Brown R. K.
Published: May 2006

not available
EFFECTS OF pH IN THE γ-RADIOLYSIS OF AQUEOUS SOLUTIONS OF CYSTEINE AND METHYL MERCAPTAN
Authors: Armstrong D. A. , Wilkening V. G.
Published: May 2006

not available
STABILITY CONSTANT OF THE BORON–DIAMINOCHRYSAZIN COMPLEX
Authors: Brown R. S.
Published: May 2006

not available
THE STUDY OF HYDROGEN BONDING AND RELATED PHENOMENA BY SPECTROSCOPIC METHODS: PART VIII. THE ULTRAVIOLET AND INFRARED SPECTRA OF SOME 2,4-DINITRODIPHENYLAMINES
Authors: Balasubramanian A. , Capindale J. B. , Forbes W. F.
Published: May 2006

The ultraviolet spectra of a number of 2,4-dinitrodiphenylamines suggest that these compounds are generally non-planar in a number of different solvents. The infrared and ultraviolet spectral data in different solvents also suggest that an intramolecular hydrogen bond is present in these molecules, at least in inert solvents. There is evidence that a p-nitro substituent is necessary to increase the positive charge on the amino group sufficiently to permit it to form this fairly strong type of hydrogen bond.
THE CHEMICAL FATE OF RECOIL IODINE ATOMS IN IODINE–METHYL IODIDE SOLUTIONS
Authors: Klassen N. V. , Baerg A. P.
Published: May 2006

The organic yield of recoil 126I, produced by the 14 MeV neutron irradiation of iodine–methyl iodide solutions, was examined over iodine concentrations from 0.34 mole fraction iodine to "pure" methyl iodide. By correcting for exchange between I2 and methyl iodide, the initial organic yield at very low iodine concentrations was found to be 57%. The time for one-half of the I2 to exchange with CH3I was found to decrease with decreasing iodine concentration. At all iodine concentrations the organic products containing 126I consisted mainly of CH3I and CH2I2. The formation of products is discussed in terms of thermal reactions, diffusion-controlled reactions in the spurs, and hot reactions.
RÉACTIONS AVEC LE DIFLUOROAMINO-PENTAFLUOROSULFURE
Authors: Boivin Jean L.
Published: May 2006

Difluoroamino-sulphur pentafluoride was prepared in quantitative yield by heating tetrafluorohydrazine and disulphur decafluoride at 150° for a period of 12 h under autogenous pressure conditions. The reactions of the product with potassium iodide, oxygen, water, hydrogen chloride, sulphur dioxide, acetone, ethyl bromide, methyl iodide, ethyl nitrite, cyanogen bromide, and acetonitrile are reported.
THE PREPARATION AND PROPERTIES OF SOME METHYL-SUBSTITUTED HEPTATRIENES
Authors: Sorensen T. S.
Published: May 2006

The synthesis and assignment of the geometry of a number of previously unknown methyl-substituted 1,3,5-heptatriens are described. A table of the ultraviolet spectral maxima of these and other trienes is included. Anomalies in the ultraviolet spectral curves of certain trienes are attributed to steric interactions affecting the coplanarity of the chromophore system.
SELF-CONDENSATION OF p-CHLOROPHENACYL CHLORIDE IN THE PRESENCE OF GRIGNARD REAGENT
Authors: Kulka Marshall
Published: May 2006

A crystalline by-product, formed in the reaction of p-chlorophenacyl chloride (I) with ethylmagnesium chloride, has been identified as 1,3-dichloro-2,4-bis(p-chlorophenyl)-2,4-hexanediol (IV). Its formation has been attributed to aldolization of I followed by reaction with Grignard reagent at the carbonyl function. The dehydrochlorination of IV yielded one of two possible compounds to which the diepoxide structure VI was assigned on the basis of n.m.r. spectra. The dehydrochlorinated product (VI) was synthesized from 1-chloro-2,3-epoxy-2,4-bis(p-chlorophenyl)-4-butanone (VIII) by treatment with ethylmagnesium chloride followed by reaction of the resulting epoxy alcohol IX with alcoholic alkali. It is suggested that the epoxy alcohol IX did not dehydrochlorinate directly to the 3,4-epoxytetrahydrofuran derivative V but instead rearranged first by epoxide alcohol transposition to X and then dehydrochlorinated to 1,2,3,4-diepoxy-2,4-bis(p-chlorophenyl)hexane (VI).
2-p-CHLOROPHENYLALKANOLS
Authors: Kulka Marshall
Published: May 2006

2-p-Chlorophenyl-1-butanol (V) has been synthesized by the condensation of p-chlorophenacyl chloride (I) with ethylmagnesium chloride and dehydrochlorination of the resulting 1-chloro-2-p-chlorophenyl-2-butanol (II) to 2-ethyl-2-p-chlorophenyloxirane (III), followed by reduction. It has been discovered that reduction of III with lithium aluminium hydride yielded the tertiary alcohol, 2-p-chlorophenyl-2-butanol (IV), while reduction of III with aluminium hydride yielded the primary alcohol V. The two alcohols IV and V were also prepared by unambiguous methods. Attempts to synthesize the higher homologues of the alcohol V were not very successful.
STRUCTURE OF MAGNESIUM ALUMINIOSILICATE LIQUIDS AT 1 700 °C
Authors: Rlebling E. F.
Published: May 2006

An improved counterbalanced sphere viscometer–densitometer was used to obtain precise viscosity and density data for melts on (a) the silica •cordierite (2MgO•2Al2O3•5SiO2) •spinel (MgO•Al2O3) join and (b) the 50 mole % SiO2line at temperatures between 1 500 and 1 720 °C. The viscosity, activation energy for viscous flow, and expansion data are indicative of a general tightening of melt flow parameters and structure as either the silica or the alumina content is increased.The density-derived data have been interpreted in terms of a model that involves no significant change of the partial molar volume of SiO2 (Vsio2). Crystalline coordination number information was used to develop a liquid molar volume model that agrees rather closely with the experimental information. This model involves AlO4tetrahedra as the major aluminium (III) species for all melts studied with Al2O3/MgO ratios equal to or less than unity. The gradual formation of MgO6octahedra from MgO4tetrahedra appears to accompany the substitution of MgO for Al2O3in melts containing 50 mole % SiO2.It has been demonstrated that a reasonable correlation can exist between the coordination number of a given cation in the crystalline state and in high-temperature liquids of similar composition.
CONTRIBUTION A L'ÉTUDE STRUCTURALE DU CÉDRÉLANOL (δ-CADINOL), ALCOOL SESQUITERPÉNIQUE C16H26O DE L'HUILE ESSENTIELLE CEDRELA ODORATA BRASILIENSIS
Authors: Smolders R. R.
Published: May 2006

not available
THE INHIBITION OF AUTOXIDATION BY 2,4,6-TRI-tert-BUTYL SUBSTITUTED PHENOL, ANILINE, AND THIOPHENOL
Authors: Gardner D. V. , Howard J. A. , Ingold K. U.
Published: May 2006

The reactions of peroxy radicals with 2,4,6-tri-t-butyl substituted phenol, aniline, and thiophenol have been examined by a kinetic method. The primary process involves abstraction of the hydrogen atom attached to the functional group, since all three compounds show fairly large isotope effects when this hydrogen is replaced by deuterium. The phenol and aniline react with about two peroxy radicals per molecule. In contrast, the thiophenol reacts with only a single peroxy radical.
ENERGY TRANSFER IN THE RADIOLYSIS OF CYCLOPENTANE–CYCLOHEXANE MIXTURES
Authors: Stone J. A.
Published: May 2006

Energy transfer in the radiolysis of cyclopentane–cyclohexane mixtures has been studied by observing the yields of HD and D2 obtained when small amounts of cyclohexane-d12 are added. Energy migration occurs from cyclopentane to cyclohexane but this transfer can be prevented by the addition of carbon tetrachloride or iodine. The relative yields of the dimers (C6H11)2, C6H9C6H11, and (C5H3)2 show that the •C6H11 and •C5H9 radicals, which are the precursors of the dimers, can abstract hydrogen atoms from the solvent and may thus change their identity. Added iodine or carbon tetrachloride removes the diffusing radicals, and the residual dimer yield, which is unaffected by solute, has a composition determined solely by the composition of the mixtures. The yields of cyclohexene and cyclopentene show evidence of both energy transfer and radical change of identity.
CARBONYL AND THIOCARBONYL COMPOUNDS: VIII. SYNTHESIS OF FLUORENE ETHERS BY THE ACTION OF TETRAHALO-o-BENZOQUINONES
Authors: Latif N. , Mishriky N.
Published: May 2006

The halogenated fluorene ethers Ic–If are directly produced by the action of tetrachloro-and tetrabromo-o-benzoquinone on the corresponding halofluorene in boiling dry benzene. The preparation of the fluorene ethers by the action of tetrahalo-o-benzoquinones on 2-chloro-and 2,7-dichloro-fluorenone hydrazone is described. The ketohydrazones are readily oxidized by mercuric oxide to the corresponding 9-diazofluorenes which react readily with the halo-quinones yielding the methylene ethers.
THE NON-CATALYTIC FISCHER INDOLIZATION OF HEXANE-2,5-DIONE BISPHENYLHYDRAZONE
Authors: Robinson B.
Published: May 2006

not available
RADIATION CHEMISTRY OF POTASSIUM PEROXYDISULFATE
Authors: Eager R. L. , Norris J. F.
Published: May 2006

not available
MANIFESTATIONS OF CHANGES WITH AGE IN SILICA HYDROGELS
Authors: Sirianni A. F. , Meadus F. W. , Puddington I. E.
Published: May 2006

not available
THE DENSITIES AND SURFACE TENSIONS OF LIQUID ETHANE AND NITROUS OXIDE
Authors: Leadbetter A. J. , Taylor D. J. , Vincent B.
Published: May 2006

not available
THE DETERMINATION OF MONOMER–DIMER SELF-ASSOCIATION EQUILIBRIUM CONSTANTS IN DILUTE SOLUTIONS
Authors: Vinogradov S. N.
Published: May 2006

not available
THE SYNTHESIS OF GLUCOSINALBIN AND GLUCOAUBRIETIN
Authors: Benn M. H.
Published: May 2006

The first synthesis of the glucosinalbin and glucoaubrietin anions has been achieved by sulfonation and deacetylation of the thiohydroximates obtained by addition of tetraacetyl-glucopyranosyl mercaptan to p-acetoxyphenylacetonitrile oxide and p-methoxyphenyl-acetonitrile oxide.
THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: IV. GALACTOMANNANS I FROM TRICHOPHYTON GRANULOSUM, TRICHOPHYTON INTERDIGITALE, MICROSPORUM QUINCKEANUM, TRICHOPHYTON RUBRUM, AND TRICHOPHYTON SCHÖNLEINII
Authors: Bishop C. T. , Perry M. B. , Blank F. , Cooper F. P.
Published: May 2006

A group of polysaccharides, called galactomannans I, were precipitated as their insoluble copper complexes from aqueous solutions of the crude polysaccharides obtained from each of the organisms designated in the title. The five galactomannans I were homogeneous under conditions of electrophoresis and ultracentrifugation and had high positive specific rotations. The major constituent monosaccharide was D-mannose; amounts of D-galactose ranged from nil for the polysaccharide from T. rubrum to 13% for that from T. schönleinii. Methylation and hydrolysis of the five galactomannans I yielded varying amounts of the following: 2,3,5,6-tetra-O-methyl-D-galactose (not present in the products from T. rubrum), 2,3,4,6-tetra-O-methyl-D-mannose, 2,3,4-tri-O-methyl-D-mannose, 2,4,6-tri-O-methyl-D-mannose, 3,4-di-O-methyl-D-mannose, and 3,5-di-O-methyl-D-mannose. Periodate oxidation results agreed with the methylation studies. The gross structural features of each galactomannan I appear to be the same, namely, a basic chain of 1 → 6 linked α-D-mannopyranose units for approximately every 22 of which there is a 1 → 3 linked α-D-mannopyranose residue. Branch points occur along the 1 → 6 linked chain at the C2 positions of the D-mannopyranose units and once in every 45 units at the C2 position of a 1 → 6 linked D-mannofuranose residue. The D-galactose in the polysaccharides is present exclusively as non-reducing terminal furanose units; non-reducing terminal units of D-mannopyranose are also present. The variations in the identities and relative amounts of the non-reducing terminal units were the only apparent differences in the gross structural features within this group of polysaccharides.
SOLVOLYSIS IN LIGHT AND HEAVY WATER: VI. THE ROLE OF INITIAL STATE STRUCTURE
Authors: Laughton P. M. , Robertson R. E.
Published: May 2006

The solubility data in light and heavy water of Swain and Thornton and of Taft and coworkers are reinterpreted to show that they support primarily the initial state origin for the kinetic solvent isotope effect. Other recent data, including the effect for t-butyl and α-phenethyl fluorides, are also shown to be compatible with the same hypothesis.
SOME ANOMALOUS CARBONYL STRETCHING FREQUENCIES IN STEROID INFRARED SPECTRA
Authors: Jones R. Norman , DiGiorgio J. B.
Published: May 2006

Abnormal C=O and C=C stretching frequencies in the infrared spectra of Δ4-3-ketosteroids containing a 19,8-lactone bridge are discussed in relation to possible conformational structures. The C=O stretching frequencies of 1,11,17-triketo-5β-steroids and Δ2-1,11,17-triketo-5β-steroids are reported. It is noted that the anomalous C=O stretching band position previously recorded for the 11-ketone in 11,17-diketosteroids is also observed in these triketones, but no additional perturbation results from the introduction of the 1-ketone group, in spite of its proximity to the carbonyl at C11.
CONCERNING THE EXISTENCE OF 2-(2-NITROVINYL)BENZOIC ACID: A CONTRIBUTION TO THE ALKALINE ELIMINATION IN β-SUBSTITUTED NITRO COMPOUNDS
Authors: Baer Hans Helmut , Kienzle Frank
Published: May 2006

Action of aqueous alkali upon 3-phthalidylnitromethane (I) is shown to produce unstable 2-(2-nitrovinyl)benzoate ion (IIa) which rapidly adds hydroxyl ion to form the dianion IVa of 2-(1-hydroxy-2-nitroethyl)benzoic acid. Both IIa and IVa revert to I upon acidification. Substitution of methoxide for aqueous alkali converts I via IIa into 2-(1-methoxy-2-nitroethyl)benzoate (Va), which is isolated as crystalline, free acid (V).
STUDIES ON THE RANGE OF 140Ba IN PROTON-INDUCED FISSION OF 238U AND A SEMI-EMPIRICAL DERIVATION OF A GENERAL RANGE–ENERGY RELATION
Authors: Mukherji S. , Yaffe L.
Published: May 2006

Ranges of 140Ba have been measured in the forward and backward directions with respect to the proton beam by bombarding uranium foils of normal isotopic composition with protons of 15, 30, and 60 MeV energies. Successive thin layers of aluminium were removed from the front and back catchers by an electrochemical technique, and the ranges were calculated from the relative distribution of 140Ba activity in the different layers. The calculations indicate that full momentum transfer of the incident protons has taken place, suggesting that the compound nucleus mechanism is predominant at these energies.An analysis of the existing range and energy data for fission fragments has shown that the 'effective charge' of a fission fragment, first postulated by Bohr, can be expressed as a function of the charge and the mass of the medium being penetrated. The original range–velocity relation of Bohr has been modified to include the above fact and has led to a general range–velocity relation for ranges in different metallic catchers. Similar equations seem to be applicable to the range data in gaseous media.
KINETICS AND MECHANISMS OF THE THERMAL DECOMPOSITION OF PROPIONALDEHYDE: PART I. THE UNINHIBITED REACTION
Authors: Laidler K. J. , Eusuf M.
Published: May 2006

The propionaldehyde pyrolysis was studied in the temperature range 520–560 °C and at pressures from 20 to 360 mm Hg. The reaction was followed by pressure change and by gas chromatography. The overall order was between 1.25 and 1.30 over the whole range of temperatures and pressures studied. Inert gases have no effect on the rates of formation of the products of reaction. The results are consistent with a mechanism consisting of first-order initiation, C2H5CHO → C2H5 + CHO, and second-order termination, C2H5 + C2H5 → C4H10 or C2H6 + C2H4. The overall rate can be expressed as v = k[C2H5CHO]3/2 + k′[C2H5CHO]1/2. The molecular reaction, C2H5CHO → C2H6 + CO, appears to be of minor importance. The reaction C2H5 → C2H4 + H was found to take place in its first-order high-pressure region under the conditions of the present investigations.
HYDROLYSIS CONSTANTS OF SOME PLATINUM(II) CHLORO COMPLEXES CONTAINING UNSATURATED LIGANDS
Authors: Allen A. D. , Theophanides T.
Published: May 2006

Hydrolysis equilibrium constants have been determined for a series of compounds of the general form K[LPtCl3], where L is a substituted dialkyl acetylene. The hydrolysis equilibrium position is only slightly affected by the nature of L, indicating that the trans metal–chlorine and metal–water bonds are similar in character.
3,5,8,4′-TETRAMETHOXYFLAVONE AND THE CONSTITUTION OF PRATOLETIN
Authors: Chadha Jaswinder Singh
Published: May 2006

not available
β-AMINOCROTONONITRILE: I. GEOMETRICAL ISOMERISM AND SOME REACTIONS
Authors: Bullock E. , Gregory B.
Published: May 2006

The low-melting form of β-aminocrotononitrile is a mixture of two components, one of which is the high-melting isomer. Isomerization reactions between the high- and low-melting forms occur very easily, reactions in solution being subject to acid–base catalysis. Self-condensation of β-aminocrotononitrile gives 4-amino-1,3-dicyano-2-methylpenta-1,3-diene which readily cyclizes to 2-amino-5-cyano-4,6-lutidine.
A SERIES OF MODEL COMPOUNDS FOR THE STUDY OF AROMATIC REACTIONS
Authors: Safe S. , Moir R. Y.
Published: May 2006

A series of halogenated phthalides was prepared in which there was a systematic variation in the identity, position, and degree of activation of the halogen, and in the activation of the methylene group. A study was made of the selective reductive removal of halogen in the presence of another halogen, or of a nitro group.
RELATIVE REACTIVITY OF TOLUENE-BENZENE IN NITRONIUM TETRAFLUOROBORATE NITRATION: LIMITATION OF THE COMPETITIVE METHOD OF RATE DETERMINATION IN FAST REACTIONS
Authors: Tolgyesi W. S.
Published: May 2006

A study was made to determine the relative reactivity of the toluene–benzene pair in a nitronium salt nitration, using the method of competitive rate determination. Despite difficulties encountered in ensuring homogeneous reaction conditions owing to the high speed of reaction the relative rates (toluene/benzene) obtained under certain conditions attained a range (25–30) which is considered to represent the range of relative reactivity and it corresponds to the known reactivity of toluene-benzene in nitric acid nitration. On the basis of these results there seems to be no reason to suppose that nitronium salt nitration involves a mechanism different from that of the nitric acid nitration.
DIFFUSION IN MULTICOMPONENT GASEOUS MIXTURES: PART 2. DIFFUSION OF XENON-I33 IN BINARY MIXTURES OF XENON WITH HELIUM, NEON, ARGON, AND KRYPTON
Authors: Watts Harry
Published: May 2006

The diffusion coefficient of trace amounts of xenon-133 has been measured in binary mixtures of xenon with helium, neon, argon, and krypton. Measurements were made over the complete composition range in the pressure range 10–300 Torr at 302.6 °K. These systems are the first studied in which the results do not agree with the equation:[Formula: see text],which relates the effective diffusion coefficient of a trace in an ideal gas mixture to binary diffusion coefficients and the composition of the mixture. Deviation from this equation can not be accounted for in terms of the known deviation of xenon from ideal gas behavior.The self-diffusion coefficient of xenon was 0.060 and the binary diffusion coefficients Xe–He 0.535, Xe–Ne 0.230, Xe–Ar 0.127, Xe–Kr 0.0823, in cm2 s−1 corrected to 1 atm pressure.
THE C- AND O-BENZYLATION OF L-ASCORBIC ACID
Authors: Jackson K. G. A. , Jones J. K. N.
Published: May 2006

Alkylation of sodium L-ascorbate with benzyl chloride yielded a 2-C-benzyl-3-keto-hexulo-sonic acid lactone and 3-O-benzyl-L-ascorbic acid, the yield of each being dependent on reaction conditions. Other products obtained from the alkylations were 2,3-di-O-benzyl-L-ascorbic acid and a 1-deoxy-1-C-phenyl-2-hexulose. Treatment of 3-O-methyl-5,6-O-iso-propylidene-L-ascorbic acid with benzyl chloride and sodium methoxide yielded the 2-O-benzyl derivative.
ION–SOLVENT INTERACTION IN MIXED SOLVENTS: PART III. THE MOLAR REFRACTION OF ELECTROLYTES
Authors: Padova J.
Published: May 2006

The apparent Lorenz-Lorentz molar refractions of Na2SO4, MgSO4, MnCl2, NaOCOCH3, Ba(OCOCH3)2, Mg(OCOCH3)2, and KOCOCH3 have been determined at 25 °C in mixtures of ethanol and acetone with water. The molar refraction of the solvated ions has been defined, and the values were calculated and found to be a linear function of the reciprocal of the dielectric constant of the bulk solvent.
MOLECULAR FORCE FIELD FOR SULFUR TETRAFLUORIDE
Authors: Pillai M. G. Krishna , Ramaswamy K. , Pichai R.
Published: May 2006

An attempt has been made to modify the UBFF for SF4 by taking into account the presence of the lone pair of electrons. It has been found that the bond pair – lone pair interactions become of importance only when the angle between the bond pair and the lone pair approaches 90°. The equatorial S—F stretching force constant (4.0146 mdyn/Å) is greater than the axial stretching force constant (3.6237 mdyn/Å), which is consistent with the form of the relationship between the force constant and bond length.
13C N.M.R. STUDIES: PART III. CARBON-13 N.M.R. SPECTRA OF SUBSTITUTED ACETOPHENONES
Authors: Dhami K. S. , Stothers J. B.
Published: May 2006

The 15.1 Mc/s 13C n.m.r. spectra of 55 substituted acetophenones have been examined and the chemical shifts of the various carbon nuclei determined. This series included a variety of monosubstituted cases (ortho, meta, and para) as well as several polysubstituted examples. The factors contributing to the observed shieldings of all carbon nuclei are considered. The aromatic shieldings are compared with previous results for other aromatic derivatives. The application of the carbonyl shifts to the study of steric inhibition of resonance in these derivatives is examined critically. The shieldings of the acetyl methyl and para-carbon nuclei are found to offer confirmatory evidence for the existence of steric hindrance to coplanarity of the acetyl group in several ortho-substituted cases.
13C N.M.R. STUDIES: PART V. CARBON-13 SPECTRA OF SOME SUBSTITUTED STYRENES
Authors: Dhami K. S. , Stothers J. B.
Published: May 2006

The 15.1 Mc/s 13C n.m.r. spectra of 23 substituted styrenes have been examined and the shieldings of the various carbon nuclei determined. Several meta- and para-substituted derivatives were included to study the effects of polar substituents on the vinyl carbon chemical shifts. In agreement with previous proposals, a linear correlation with the Hammett σ parameter is found for the β-carbon shieldings, but not for those of the α-carbons. Nine ortho-substituted examples and two α-substituted compounds were investigated to compare their chemical shifts with results for related carbonyl compounds. While the 13C data exhibit marked differences in the hindered compounds, the variations differ from those observed in the more polar carbonyl systems.
THE IONIZATION BEHAVIOR OF AMIDES IN CONCENTRATED SULFURIC ACIDS: II. APPLICATIONS OF THE HA FUNCTION TO RATES AND EQUILIBRIA
Authors: Yates Keith , Stevens Joan B.
Published: May 2006

The newly determined HA, scale of acidity has been tested against ionization ratio data for 33 amides. Twenty-nine of these compounds give log I vs. HA slopes of 0.9–1.1 and most are within 0.95–1.05. The average slope for these is 1.001 ± 0.051. The HA function is thus considered to be generally applicable to the ionization of this type of base, and the significance of previously reported amide pK values is discussed in the light of these results. Previously reported basicity – substituent constant relations have been reexamined using thermodynamically significant pK data and earlier conclusions confirmed. Appropriate equations are derived in an attempt to explain the rate–acidity dependence of amide hydrolysis directly in terms of the water activity of the reaction medium. The picture of the hydrolysis transition state which results is in accord with that obtained using methods described by other workers.
FREE RADICALS BY MASS SPECTROMETRY: XXXII. THERMAL DECOMPOSITION OF CYCLOPENTYL RADICALS
Authors: Palmer T. F. , Lossing F. P.
Published: May 2006

At low pressures and elevated temperatures cyclopentyl radicals are found to dissociate mainly by two modes of reaction: about 34% by loss of H atom to form cyclopentene, and about 66% by a C—C bond rupture to form ethylene and allyl radicals. Under the conditions employed no evidence for a third possible mode, the loss of H2to form cyclopentenyl radical, could be found. It is estimated that an incidence of 2% of the latter could have been detected.
13C N.M.R. STUDIES: PART VI. CARBON-13 SPECTRA OF α,β-UNSATURATED CARBONYL COMPOUNDS
Authors: Marr D. H. , Stothers J. B.
Published: May 2006

The 15.1 Mc/s 13C n.m.r. spectra of 34 α,β.-unsaturated carbonyl compounds have been obtained and the chemical shifts of the olefinic and carbonyl carbon nuclei are reported. Examples were drawn from the acyclic and five- and six-membered ring alicyclic series. A few aldehydes are included although most of the compounds are ketones. In the case of compounds assumed to be planar, variations of the olefinic shieldings with alkyl substitution parallel those observed previously for olefinic hydrocarbons. The key factor governing the chemical shifts of the carbonyl-carbon nuclei appears to be the extent of conjugation in a given system. Consequently, the 13C results provide evidence for steric interference to coplanarity in the hindered systems. This approach is compared with other methods of estimating the extent of steric inhibition of conjugation and its merits are assessed.
RADIATION CHEMISTRY OF ALKALI THIOSULFATES
Authors: Eager R. L. , Mahadevappa D. S.
Published: May 2006

The salts Na2S2O3, Na2S2O3•5H2O, K2S2O3, and [Formula: see text] were irradiated at room temperature with 60Co gamma rays. When the irradiated salts were dissolved in water, sulfite and sulfate ions, H2S gas, colloidal sulfur, and a relatively small quantity of acid were found among the irradiation products. The dependence of yields on the absorbed dose was studied. G-values of approximately unity were found. Using 35S as a label, it was found that the inner sulfur (the central, oxygen-bonded sulfur atom of the complex) appears in the sulfite and sulfate whereas the outer sulfur (the sulfur linked only to the central sulfur and not to oxygen) appears in the H2S and colloidal sulfur. Annealing experiments using irradiated Na2S2O3 and K2S2O3 showed that the yields of sulfite, sulfate, and H2S were decreased by heating. The sodium salts were also irradiated at 77°K. The yields of sulfate and H2S were higher for the low temperature irradiations as compared to room temperature irradiations, whereas the yields of sulfite were lower. A tentative mechanism which partially explains the results is proposed.