bluuebunny/crossref_metadata_2025 huggingface dataset:
THE RADIOLYSIS OF ETHANOL: IV. DEUTERATED ETHANOLS IN THE LIQUID AND GAS PHASES
Authors: Myron J. J. J. , Freeman G. R.
Published: May 2006

The value of G(–ethanol) in the vapor phase is nearly double that in the liquid phase. Part of the difference appears to be due to the recombination of radicals in liquid cages. Ethanol molecules, on the average, break into smaller fragments in the gas than in the liquid phase radiolysis. The isotopic compositions of the hydrogen produced from various deuterated ethanols are consistent with the suggestion that the reaction[Formula: see text]occurs to a significant extent in the liquid but not in the gas phase. This reaction probably involves the shift of a hydrogen atom along a hydrogen bond. The reaction[Formula: see text]does not occur to an appreciable extent in the liquid phase. In the liquid phase the relative contributions of the three different groups in the ethanol molecule to hydrogen production are in the order [Formula: see text] A similar trend occurs in the gas, although the contributions of the three groups are more nearly equal in this phase. Isotope effects, in the range kH/kD = 2.2–3.9 per bond, occur in the methane formation mechanism. The isotope effects are somewhat smaller in the liquid than in the vapor phase and somewhat smaller in the inhibited than in the uninhibited systems. A comparison of product distributions in the liquid and gas radiolyses of several compounds by γ-rays and by α-particles indicates that L.E.T. effects can also occur in the gas phase.
SEMIEMPIRICAL SCF–LCAO–MO TREATMENT OF THIOPHENE, FURAN, AND PYRROLE
Authors: Solony N. , Birss F. W. , Greenshields John B.
Published: May 2006

The semiempirical SCF–LCAO–MO method of Pariser–Parr–Pople is utilized in the study of the π-electronic structures of thiophene, furan, and pyrrole. The core Hamiltonian expansion contains a Uz++ term, the potential due to the ionized hetero-atom contributing two electrons to the π-system. The γzz, one-center coulomb repulsion integral for the hetero-atom is evaluated from the experimental spectroscopic data only. With the resonance integral βczc as the only variable parameter, the calculated π*–π electronic transitions are in a satisfactory agreement with the experimental data.
CONFORMATIONAL STUDIES ON SYNTHETIC POLY-α-AMINO ACIDS: THE HELICAL SENSE OF POLY-L-TRYPTOPHAN: OPTICAL ROTATORY DISPERSION STUDIES
Authors: Fasman Gerald D. , Landsberg Margarete , Buchwald Manuel
Published: May 2006

The synthesis of high molecular weight (100 000 to 200 000) polymers and copolymers of L-tryptophan and γ-benzyl-L-glutamate is reported. The optical rotatory dispersion (o.r.d.) of these polypeptides is recorded in the wavelength range 540–320 mμ and the b0 values of the Moffitt equation, using λ0 = 212ν, are listed. Poly-L-tryptophan has a b0 value of +570 in dimethylformamide (DMF). A linear relationship exists between this value, b0 values of copolymers of various ratios of L-tryptophan and γ-benzyl-L-glutamate, and the value of− 670 found for poly-γ-benzyl-L-glutamate. The o.r.d. curve of a poly-L-tryptophan film, in the 330–200 mμ wavelength range, reveals two positive Cotton effects in the 270–290 mμ region and a large negative Cotton effect at 233 mμ. Thus, despite the positive b0 value, these data prove that poly-L-tryptophan, in DMF, has the right-handed helical conformation. Hypochromicity was found for the tryptophanyl residue in the helical polypeptide. The rotatory contribution of chromophores, such as tryptophan or coenzymes, when bound asymmetrically to a protein, can be very significant, and caution is advised in the interpretation of such o.r.d. curves.
ISOMERIC SYDNONES: I. THE REACTIONS OF 1- AND 2-BENZOYL-1-METHYLHYDRAZINES AND PHOSGENE
Authors: Ainsworth C.
Published: May 2006

The oxygen–carbonyl isomeric sydnone (V) has been synthesized from 1-benzoyl-1-methyl-hydrazine hydrochloride (VII) and phosgene. The isosydnone V itself reacts with phosgene to form 2-chloro-5-phenyl-1,3,4-oxadiazole (VI), a new substituted 1,3,4-oxadiazole. Thermal rearrangement of the salt VII takes place at 200° to give 1-benzoyl-2-methylhydrazine, which with phosgene forms the isomer XI. Some mechanistic pathways for these transformations are discussed.
DELPHINIUM ALKALOIDS THE STRUCTURES OF THE ALKALOIDS OF DELPHINIUM CARDINALE HOOK AND THE ALKALOID DELATINE
Authors: Benn M. H.
Published: May 2006

Browniine, dehydrobrowniine, lycoctonine, hetisine, and a dehydrohetisine were isolated from Delphiniumcardinale Hook. Delatine, an alkaloid previously isolated from D. elatum L., was found to be hetisine. These are the first examples of the occurrence of the Aconitum alkaloid hetisine in Delphinium spp.
CHARGE-TRANSFER COMPLEXES OF BIPHENYLENE
Authors: Emslie P. H. , Foster R. , Pickles R.
Published: May 2006

An attempt has been made to redetermine the enthalpy and entropy of formation of the charge-transfer complex between tetracyanoethylene and biphenylene in dichloromethane solution from measurements of the equilibrium constant at different temperatures. The results obtained under conditions where biphenylene is in excess differ from those previously published in which tetracyanoethylene was in excess. It is argued that the optimum condition for determining equilibrium constants of a 1:1 complex is when the reactants are mixed in solution in this ratio. Determinations under this condition yield ΔH = −2.6 kcal mole−1and ΔS = −4.1 e.u.The energies of the intermolecular charge-transfer transitions of biphenylene with several different acceptors suggest that the ionization potential of biphenylene is ~7.4 eV.
1,2,3,4-TETRAPHENYLDIAZETIDINE: A REEXAMINATION
Authors: Smith J. G.
Published: May 2006

The reported synthesis of 1,2,3,4-tetraphenyldiazetidine by treating the sodium adduct of N-benzylidene aniline with benzaldehyde or benzoate ester is reexamined. It is shown that the original report is in error. The products from the reaction are the two diastereomeric N-benzoyl-N,N′,1,2-tetraphenylethylenediamines and dd,ll-N,N′, 1,2-tetraphenylethylenediamine. When diethyl ether was used as a reaction medium, another product, N-benzoyl-N,N′-diphenylstilbene-α,α′-diamine, was formed. An explanation is offered for the formation of these compounds and for the differences in reaction products caused by the two reaction media employed, diethyl ether and te trahydrofuran.
STRUCTURES OF CHLOROBIUM CHLOROPHYLLS (660)
Authors: Holt A. S. , Purdie J. W. , Wasley J. W. F.
Published: May 2006

The Chlorobium chlorophylls (660) consist of six different pigments, all of which are derivatives of δ-alkyl-2-desvinyl-2-α-hydroxyethylpyropheophorbide.α The six compounds differ in their substituents at C4(isobutyl, n-propyl, ethyl), C5(ethyl, methyl), and Cδ(ethyl, methyl).
THE ALCOHOLYSIS OF TRIALKYLALKOXYSILANES: PART II. THE PREPARATION AND CHEMISTRY OF METHYL 2,3,4-TRI-O-TRIMETHYLSILYL-α-D-GLUCOPYRANOSIDE
Authors: Hurst D. T. , McInnes A. G.
Published: May 2006

not available
PROTON MAGNETIC RESONANCE LINE WIDTH AS A FUNCTION OF POLYMER TACTICITY
Authors: Brownstein S. , Wiles D. M.
Published: May 2006

The high resolution proton magnetic resonance spectra of five samples of poly(methyl methacrylate) in chloroform solution have been measured with 100 Mc/s equipment. The widths of the absorption lines arising from the protons of the α-methyl and the methoxyl groups have been compared. The widths are greater when the polymer is predominantly syndiotactic than when it is predominantly isotactic. It is concluded that isotactic samples have the more extended conformation in chloroform solution. An analogy with dilute solution viscosity measurements is outlined in support of this conclusion. Differences between the widths of the lines of the methylene protons in a completely isotactic poly(methyl methacrylate) sample are attributed to long range spin coupling.
THERMAL OXIDATION OF SARAN CARBON: PART I. STUDIES UNDER STATIC OXYGEN SYSTEM
Authors: Barradas R. G. , Dignam M. J. , Chadha D. D.
Published: May 2006

Oxidation studies from 425 to 600 °C of porous carbons obtained from the pyrolytic decomposition of pure polyvinylidene chloride have been carried out in static oxygen systems. Measurements of weight change were made by means of a sensitive thermal microbalance. Empirical activation energies for the oxidation reaction were determined to be approximately 1 eV in magnitude, and comparison is made with previously published results for graphite. Carbon samples obtained from polymers compressed at different molding pressures showed somewhat different temperature and pressure rate dependence. An unusual pressure dependence was observed for the rate of reaction, and a tentative explanation is offered.
A PERTURBATION CALCULATION OF THE EFFECT OF ELECTRIC INTERACTION ON PROTON MAGNETIC SHIELDING
Authors: Yonemoto T.
Published: May 2006

The effect of electric interaction of molecular systems on proton magnetic shielding is calculated by a perturbation method, and a general expression of this effect is obtained. It is shown that the effect consists of three parts. Two of them are dependent on the time average of the field at the proton, and correspond to the linear and the square terms of Buckingham's equation of the (external) electric field effect. The third part is proportional to the van der Waals interaction energy between the hydrogen and the interacting object. The magnitude of the former two terms is calculated for a polarized hydrogen atom and a hydrogen molecule. The van der Waals deshielding caused by halogen atoms is also estimated.
THE SYNTHESIS OF PORPHYRINS DERIVED FROM CHLOROBIUM CHLOROPHYLLS
Authors: Archibald J. L. , Walker D. M. , Shaw K. B. , Markovac A. , MacDonald S. F.
Published: May 2006

The proofs of the structures proposed for the Chlorobium pheophorbides 650, fractions 1–5, and for the Chlorobium pheophorbides 660, fractions 5 and 6, are completed and the degradational evidence, where parallel, confirmed through the synthesis of derived porphyrins.
THE SYNTHESIS OF 5-DIMETHYLAMINOINDOLE AND DERIVATIVES
Authors: DeGraw Joseph I.
Published: May 2006

The preparation of 5-dimethylaminoindole is described. This compound underwent the usual reactions typical of 3-unsubstituted indoles, and various 3-substituted derivatives were prepared. Syntheses for 5-dimethylaminotryptophan, 5-dimethylaminotryptamine, 5-dimethylamino-N,N-dimethyltryptamine, and 5-dimethylamino-α-methyltryptamine are reported.
RADIATION-INDUCED BROMINATION OF 2,3-DIMETHYLBUTANE
Authors: Wheeler Owen H. , Batlle de Pabon Hilda
Published: May 2006

not available
ORGANIC SULFUR MECHANISMS: III. A BRIEF INVESTIGATION INTO THE REACTION OF BENZONITRILE OXIDE WITH SULFENES
Authors: King J. F. , Durst T.
Published: May 2006

not available
THE SEPARATION OF ALDOPENTOSE AND ALDOHEXOSE DIETHYL DITHIOACETAL DERIVATIVES BY GAS–LIQUID PARTITION CHROMATOGRAPHY
Authors: Williams D. T. , Jones J. K. N.
Published: May 2006

not available
CONCERNING THE REACTION BETWEEN MALEIC ANHYDRIDE AND INDENE
Authors: Isaacs Neil S.
Published: May 2006

not available
SECOND VIRIAL COEFFICIENTS AND INTERMOLECULAR FORCES FOR THE AMMONIA–ACETYLENE SYSTEM
Authors: Cheh H. Y. , O'Connell J. P. , Prausnitz J. M.
Published: May 2006

Volumetric data for gaseous ammonia–acetylene mixtures have been analyzed to obtain second virial coefficients as a function of temperature and composition. From the pure-component virial coefficients of ammonia and acetylene, Kihara-potential parameters were obtained and these were used to calculate the physical contributions to the second cross virial coefficients, B12. The difference between the experimental B12 and that calculated from the physical contribution is attributed to chemical interaction, or complex formation, between the two molecules. Chemical equilibrium constants have been calculated, and ΔH0 and ΔS0 for complex formation were found to be −(2 210) cal/mole and −16.6 cal/mole °K respectively. These results indicate very weak hydrogen bond formation between the nitrogen atom in the ammonia and the hydrogen atom in acetylene.
VISIBLE AND ULTRAVIOLET ABSORPTION SPECTRA OF RHODIUM(III) IN FUSED ALKALI CHLORIDES AND NITRATES
Authors: Ogilvie Fredrick B. , Holmes Owen G.
Published: May 2006

The spectrum of RhCl3 in fused LiCl–KCl at 440 °C is sufficiently different from that of RhCl63− to suggest the existence of some other species such as dimeric or polymeric bridge-complexes, or, less likely, tetrahedral RhCl4−. The spectra of RhCl3 and K3Rh(NO2)6 in fused NaNO3–KNO3 at 300 °C indicate the occurrence of nitro coordination in both systems, probably completely in the latter case, but in competition with chloro coordination in the former. Addition of KCl to a solution of RhCl3 in NaNO3–KNO3 causes spectral changes which suggest that RhCl63− is the principal rhodium species present.
THE RANGES OF INTERACTIONS IN THE RADIOLYSIS OF SOLID HYDROCARBON MIXTURES
Authors: Dyne P. J. , Denhartog J.
Published: May 2006

We describe a novel technique for measuring the ranges of interaction in the radiolysis of hydrocarbon mixtures, e.g. the distance between donor and acceptor molecules in an energy transfer process. Thin layers, 20 to 1 000 Å thick, of solid c-C6D12 sandwiched between other materials which activate or deactivate the hydrocarbon, are irradiated. The yields of D2 and HD are measured as a function of the layer thickness. These yields change rapidly when the layer thickness is comparable with the range of the interaction.We find: (a) the activation of c-C6D12 by n-C6H14 has a very short range consistent with an ionmolecule reaction between nearest neighbor molecules; (b) the deactivation by CCl4 or benzene has a longer range (180 Å or more) consistent with the average separation of positive ions and electrons in an irradiated hydrocarbon; (c) the intermediates in the bimolecular reaction giving HD in layers of C6D12 and C6H12 have a short range (< 100 Å) and cannot be thermal hydrogen atoms.
DIFFUSION IN MULTICOMPONENT AQUEOUS SYSTEMS
Authors: Lane J. E. , Kirkaldy J. S.
Published: May 2006

A vacancy model, originally developed for the description of diffusion in substitutional alloys, is modified for application to aqueous solutions, including those containing ionic species. The results obtained with this model are similar to those of two recently published methods for estimating L-coefficients in dilute multicomponent liquid systems.Agreement with experimental L-coefficients at relatively high concentrations can be improved for this model by assuming that the jump probability of a diffusing species is inversely proportional to the relative viscosity of the mixture. Good agreement is then found for some systems up to combined solute concentrations of 3 M.
THE CHEMISTRY OF IRIDIUM IN BASIC AQUEOUS SOLUTION: A POLAROGRAPHIC STUDY
Authors: Loon Gary Van , Page John A.
Published: May 2006

The polarographic behavior of iridium(IV) has been studied in basic solutions at 25 °C at an ionic strength maintained with sodium chloride at 0.50 M. Between pH 11.3 and 13.0, a reversible, diffusion-controlled, one Faraday per mole reduction wave was obtained. The E1/2 was −0.60 V versus a saturated calomel reference electrode at pH 12.0; a shift of −57 mV per pH unit indicated that one hydrogen ion is involved in the reduction. With basic solutions of iridium(III), the corresponding oxidation wave was obtained, but the metal was easily air oxidized. The basic iridium(IV) species gave an absorption peak at 313 mμ. The rate of formation of the basic iridium(III) complex from an acid iridium(III) solution was found to be more rapid than that of the basic iridium(IV) complex from an acid iridium(IV) solution. The reaction of iridium (IV) with ethylenediaminetetracetate was also studied.
THE CHEMISTRY OF THE AMINOCHROMES: IX. THE REACTIONS OF GLUTATHIONE WITH SOME HALOGENATED AMINOCHROMES
Authors: Mattok G. L. , Heacock R. A.
Published: May 2006

7-Iodoadrenochrome reacts with glutathione to give 5,6-dihydroxy-7-iodo-1-methylindole, 5,6-dihydroxy-1-methylindole, 7-S-glutathionyl-5,6-dihydroxy-1-methylindole, and a trace of a product that is probably 4-S-glutathionyl-5,6-dihydroxy-7-iodo-1-methylindole. It reacts with the monosodium salt of glutathione to give mainly 5,6-dihydroxy-7-iodo-1-methylindole and 4-S-glutathionyl-5,6-dihydroxy-7-iodo-1-methylindole, with smaller quantities of 7-S-glutathionyl-5,6-dihydroxy-1-methylindole and 5,6-dihydroxy-1-methylindole. 7-Bromoadrenochrome reacts with glutathione (free acid or monosodium salt) to give mainly 7-bromo-5,6-dihydroxy-1-methylindole and a second product, which is probably 7-bromo-4-S-glutathionyl-5,6-dihydroxy-1-methylindole. The main products that are obtained in reactions of this type result from either direct reduction of the aminochrome or 1,4-addition of the thiol to either of the α,β-unsaturated C5-carbonyl systems in the aminochrome molecule.
THE REACTION OF CHLORAL WITH HALOBENZENES AND WITH 2,4-DICHLOROPHENOL: SYNTHESIS OF HALOGENATED ETHYLBENZENES AND OF α-METHOXYPHENYLACETIC ACIDS
Authors: Reeve Wilkins , Mutchler John P. , Liotta Charles L.
Published: May 2006

The Friedel–Crafts reaction of chloral with aromatic compounds to form aryltrichloromethylcarbinols is reviewed. The molar ratio of aluminium chloride to chloral is critical and varies from 0.15 to 2.0 depending on the solvent, steric considerations, and the reactivity of the aromatic ring. The reaction has been used to prepare several new compounds with carbon disulfide or excess aromatic compound as the solvent. From 2,4-dichlorophenol, an o-hydroxy-α-trichloromethylbenzyl alcohol is obtained. Both the phenolic and side-chain hydroxy groups of this alcohol are methylated with equal ease by dimethyl sulfate.It has now been found that changing the solvent from carbon disulfide to methylene chloride results in the hydroxy group of the initial carbinol also being replaced by chlorine. This role of the solvent in controlling the course of the reaction has not been observed previously.The trichloromethylcarbinols are converted into α-methoxy acids by treatment with methanolic potassium hydroxide. Sodium in liquid ammonia removes the α-methoxy group, as well as the halogens, from 3,5-dichloro-α,2-dimethoxyphenylacetic acid.
REDUCTIVE CLEAVAGE WITH METAL IN LIQUID AMMONIA: I. THE SELECTIVE CLEAVAGE OF THE BENZYLTHIO C—S BOND VERSUS THE BENZYLIDENEDIOXY C—O BOND IN METHYL S-BENZYL-4,6-O-BENZYLIDENE-2-THIO-α-D-ALTROPYRANOSIDES; THE INFLUENCE OF THE COSOLVENT 1,2-DIMETHOXYETHANE ON THE COURSE OF THE REACTION
Authors: Nayak U. G. , Brown R. K.
Published: May 2006

The improved solubility of methyl S-benzyl-4,6-O-benzylidene-2-thio-α-D-altropyranoside (1) in liquid ammonia diluted with 1,2-dimethoxyethane has permitted the selective cleavage by metallic sodium or lithium of the C—S bond to give methyl 4,6-O-benzylidene-2-thio-α-D-altropyranoside in 70–75% yield. On the other hand, the slight solubility of I in liquid ammonia alone results only in the completely hydrogenolyzed material, methyl 2-thio-α-D-altropyranoside, along with unchanged I.Generally, in liquid ammonia alone, reductive cleavage is rapid (15–20 min) and the benzylidene and benzyl groups are converted largely into toluene accompanied by a small amount of bibenzyl. In liquid ammonia – 1,2-dimethoxyethane mixtures the reaction is much slower (≥ 1.5 h); under these conditions the benzylidene and benzyl groups are converted to a larger extent into bibenzyl, the rest becoming toluene.The two strong infrared absorption bands (in Nujol) in the region of 766 to 778 cm−1 and 706 to 718 cm−1 have been assigned to the phenyl moiety of the benzylidene group, and the one strong band in the region of 702 cm−1 to the phenyl moiety of the S-benzyl group.
THE ANIONIC POLYMERIZATION OF ALLYL ACRYLATE AND OF ALLYL METHACRYLATE
Authors: Bywater S. , Black P. E. , Wiles D. AM.
Published: May 2006

The low temperature polymerization of allyl acrylate in toluene solution has been investigated with n-butyllithium and 1,1-diphenyl-n-hexyllithium initiators. The latter was also used in a study of the polymerization of allyl methacrylate under the same conditions. The reactions between initiator and monomer were rapid in all cases. More than half of the initiator molecules reacted with monomer acrylic double bonds to start polymer chains, only a few of which grew to a high molecular weight, highly isotactic product. Most of the chains remained as a low molecular weight, precipitant-soluble product. The remaining initiator molecules reacted with the carbonyl groups of the monomers to produce species which could be detected as allyl alcohol, after termination of the reaction with acetic acid. The allyl double bonds were not involved in reactions during polymerization but were presumably responsible for the cross-linking which occurred when the polymers were exposed to air.
THE REACTION OF HEXAFLUOROACETONE WITH SILANOLS
Authors: Janzen A. F. , Willis C. J.
Published: May 2006

not available
ANTINEOPLASTIC AGENTS: XVII. N-(2-BROMOETHYL)-N-(2-CHLOROETHYL)AMINES
Authors: Pettit George R. , Chamberland Maurice R.
Published: May 2006

A convenient synthesis (I → IVa) starting with N-bis(2-chloroethyl)amine has been devised for obtaining N-(2-bromoethyl)-N-(2-chloroethyl)amine. Several N-alkyl (IVb and VIII) and N-benzyl (VII) derivatives of the unsymmetrically halogenated amine (IVa) were prepared for cancer chemotherapeutic evaluation.
THE REACTION OF PHENYLMETHANESULFONYL CHLORIDE WITH TERTIARY AMINES: FORMATION OF GEOMETRICAL ISOMERS ABOUT A CARBON–SULFUR DOUBLE BOND
Authors: King J. F. , Durst T.
Published: May 2006

In methylene chloride or ether solution, phenylmethanesulfonyl chloride reacts with triethylamine to give a mixture consisting primarily of trans-stilbene and cis diphenylethylene sulfone. In cyclohexane the same reagents yield principally a material which is shown to be a roughly 2:1 mixture of cis- and trans-oxythiobenzoyl chlorides (I and II, respectively). The latter compounds represent the first examples of geometrical isomerism about a double bond in which one of the atoms of the double bond is outside the first short period of the Periodic Table.
THE OXIDATION OF 1,2;5,6-DI-O-ISOPROPYLIDENE-D-GLUCOSE BY DIMETHYL SULFOXIDE – ACETIC ANHYDRIDE
Authors: Sowa W. , Thomas G. H. S.
Published: May 2006

not available
REACTION OF AROYL HALIDES WITH AROMATIC ALDEHYDES AND ACETOPHENONES
Authors: Filler Robert , Miller Fredric N.
Published: May 2006

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REARRANGEMENT STUDIES WITH 14C XXVI. SOLVOLYSES OF 2-(β-NAPHTHYL)-1-14C-ETHYL p-TOLUENESULFONATE
Authors: Lee C. C. , Forman A. G.
Published: May 2006

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THE RELATIVE ACCEPTOR POWER OF BORON TRIHALIDES TOWARD ACETONITRILE BY PROTON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS
Authors: Miller J. M. , Onyszchuk M.
Published: May 2006

Proton nuclear magnetic resonance spectra of BF3, BCl3, and BBr3 adducts of acetonitrile have been measured in nitrobenzene solution. Single peaks were observed in each case and chemical shifts relative to tetramethylsilane decreased in the order BBr3 > BCl3 > BF3, suggesting that this is the order of acceptor activity toward acetonitrile. Linear relationships exist between methyl proton chemical shifts of CH3CN•BX3 and the heats of formation, dipole moments, and infrared vibrational shifts of the same or related adducts.
EVIDENCE FOR THE INFLUENCE OF TRACES OF HYDROGEN HALIDES IN HALOGEN EXCHANGE REACTIONS
Authors: Rand Myron J. , Reizman Fremont
Published: May 2006

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STEROIDS AND STEROIDASES: I. LONG-RANGE EFFECTS AND THE PREPARATION OF A-HOMOSTEROIDS
Authors: Jones J. Bryan , Price Philip
Published: May 2006

The direction of the diazomethane ring enlargement of 17β-hydroxy-5α-androstan-3-one (I, R = OH) appears to be controlled by the long-range effect of the 17β-hydroxyl group, and proceeds with migration of the C3—C4 bond to give the A-homo-3-one III (R = OH). This is in direct contrast to the rearrangement of 5α-cholestan-3-one (I, R = C8H17), which gives the A-homoketone II (R = C8H17) as a result of C2—C3 bond migration. An analogous directing effect was not observed for the reaction of diazomethane with 17β-hydroxy-5β-androstan-3-one (VII). Oxidation of the A-homo-17β-alcohols gave the corresponding diones III (R = =O), X, and XI.
POLAROGRAPHIC HALF-WAVE POTENTIALS OF SOME 1,4-NAPHTHOQUINONES
Authors: Currie D. J. , Holmes H. L.
Published: May 2006

The half-wave potentials for the reduction of 103 substituted 1,4-naphthoquinones were measured in 75% v/v aqueous ethanol containing buffer components. In general, if two constants were assigned, one characteristic of monosubstitution and the other characteristic of disubstitution, it was possible, by assuming additivity of the constants, to predict the half-wave potentials of the compounds within the experimental accuracy of the polarographic method.
CHEMISTRY OF TETRAHYDROFURANONE DERIVATIVES: II. A CONVENIENT PROCEDURE FOR THE SYNTHESIS OF 3-ALKYL-SUBSTITUTED FURANS
Authors: Gianturco M. A. , Friedel P.
Published: May 2006

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SYNTHESIS OF CHLORINATED 2-(3-BENZOFURANYL)PHENOLS
Authors: Coxworth E. C. M.
Published: May 2006

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STEROIDS AND RELATED NATURAL PRODUCTS XXIX. SODIUM BOROHYDRIDE – BORON TRIHALIDE REDUCTION OF 3-OXO-4-OXA-5α-CHOLESTANE
Authors: Pettit George R. , Evers William J.
Published: May 2006

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POTENTIAL ANTICANCER AGENTS III. URETHANE-TYPE NITROGEN MUSTARDS OF SOME SYNTHETIC ESTROGENS
Authors: Niculescu-Duvăz I. , Feyns V. , Grant E. , Tărnăuceanu E.
Published: May 2006

not available
SORPTION OF HYDROGEN AND OXYGEN BY CADMIUM OXIDE
Authors: Low M. J. D. , Kamel A. M.
Published: May 2006

The sorptions of hydrogen and of oxygen on freshly prepared and on gas-treated cadmium oxide were measured from 0 to 250 °C. The data suggest that hydrogen chemisorption predominates near 26°, where it is the precursor of water formed on the surface. Surface reduction occurs at temperatures as low as 50°. At least two types of oxygen sorption exist. The isobar has a minimum near 50°. Chemisorption occurs below 50° and the sorption kinetics indicates the presence of two types. The incorporation of oxygen into the bulk may account for the observed increased sorption above 150°.
THE SULFURIC ACID SOLVENT SYSTEM: PART VIII. SOLUTIONS OF SOME PHOSPHORUS(V) AND VANADIUM(V) COMPOUNDS
Authors: Gillespie R. J. , Kapoor R. , Robinson E. A.
Published: May 2006

It is shown that a number of phosphates ionize in sulfuric acid to give the P(OH)4+ion. Triphenyl phosphine and triethyl phosphate are fully protonated but phosphorus oxyfluoride and phosphorus oxychloride are shown to be nonelectrolytes.Ammonium metavanadate and vanadium pentoxide give the acid H[VO(HSO4)4] and there is evidence that the dimer H[V2O3(HSO4)6] and possibly higher polymers are present in increasing amounts with increasing concentration.
DIMETHYLTRIFLUOROACETYLARSINE AND RELATED COMPOUNDS
Authors: Cullen W. R. , Styan G. E.
Published: May 2006

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THE ALKALOIDS OF PAPAVERACEOUS PLANTS: LV. A NEW ALKALOID, ESCHSCHOLTZIDINE, AND ITS STRUCTURE
Authors: Manske Richard H. F. , Shin Kju Hi
Published: May 2006

A very small amount of a new alkaloid, eschscholtzidine, present in E. californica, was shown to be eschscholtzine in which a methylenedioxy group is replaced by two methoxyls.
EFFECT OF INTRAMOLECULAR HYDROGEN BONDING ON IONIZATION CONSTANTS OF SUBSTITUTED SALICYLIC ACIDS
Authors: Dunn G. E. , Kung Fei-lin
Published: May 2006

Ionization constants at 25 °C have been determined by a spectrophotometric method for 17 substituted salicylic acids. These have been fitted to the simple Hammett relationship and to the extended one proposed by Jaffe, which takes into account the transmission of substituent effects by the o-hydroxy group. The results with Jaffe's equation show that substituent effects on acidity are transmitted only slightly, if at all, through the intramolecular hydrogen bond of a chelate ring. Possible interpretations of the results are discussed.
STEREOCHEMICAL STUDIES: VI. REACTIONS OF 3β-HYDROXY-4-OXA-5α-ESTRANE AND 3α,17β-DIHYDROXY-4-OXA-5α-ESTRANE
Authors: Edward J. T. , Ferland J.-M.
Published: May 2006

The configurations at the 3 positions of 3β-hydroxy-4-oxa-5α-estrane and of 3α, 17β-dihydroxy-4-oxa-5α-estrane were assigned from a study of the anomerizations of these compounds in aqueous tetrahydrofuran. 3α-Chloro-4-oxa-5α-estrane solvolyzed in alkaline methanol to give a mixture of 3α- and 3β-methoxy-4-oxa-5α-estrane, the former predominating. The difference in the solvolytic behavior of 3α-chloro-4-oxa-5α-steroids and of α-glycosyl halides is discussed.
SUGAR ESTERS: III. NEW REAGENT FOR DEOXYHALO SUGAR PREPARATION
Authors: Lee J. B. , Nolan T. J.
Published: May 2006

not available
THE INFLUENCE OF TEMPERATURE ON THE STEREOCHEMISTRY OF THE ADDITION OF p-CHLOROBENZENESULFENYL CHLORIDE TO cis- AND trans-2-BUTENE
Authors: Schmid George H. , Csizmadia Valeria M.
Published: May 2006

not available
REACTIONS OF THERMAL ENERGY IONS: II. RATES OF SOME HYDROGEN TRANSFER ION–MOLECULE REACTIONS
Authors: Harrison A. G. , Ivko A. , Shannon T. W.
Published: May 2006

The rate constants for the ion–molecule reactions forming the protonated molecule in CH3CN, H2, CH4, and CH3OCH3, the equivalent reactions in the deuteriated species, and the reactions forming COD+ in CO–CD4 mixtures have been measured at thermal energies and at 10.5 V/cm repeller field strength. For H2, HD, D2 and the reactions in CO–CD4 mixtures the rate constant for the thermal reaction is approximately 0.3–0.5 that of the 10.5 V/cm rate constant. For all other cases the ratio of rate constants is approximately unity as predicted by the ion-induced dipole model. The absolute values of the rate constants in most cases are considerably lower than predicted by theory.
THERMAL DECOMPOSITION OF MOLECULAR COMPLEXES: IV. FURTHER STUDIES OF THE β-QUINOL CLATHRATES
Authors: McAdie H. G.
Published: May 2006

The endothermal decomposition of 18 β-quinol clathrates has been studied by thermo-analysis, calorimetry, and X-ray diffraction, and the decomposition process shown to be[Formula: see text]For those symmetrical guest molecules (M) which do not distort the β-quinol cavities from their normal dimensions, both temperatures and enthalpies of clathrate decomposition increase with increasing volume of the guest molecule. For those unsymmetrical guest species which require distortion of the cavities along their c-axis, temperatures and enthalpies of decomposition tend to decrease as the initial distortion required to accommodate the guest increases. Thermal stability of β-quinol clathrates is thus strongly influenced both by the size and shape of the guest molecule.The mechanism of thermal decomposition is suggested to involve a combination of the loss of stabilizing guest–wall interactions, together with increased thermal motion of the interpenetrating networks of hydrogen-bonded quinol molecules.
THE REACTION OF METHANESULFONIC ACID WITH SULFUR TRIOXIDE
Authors: Robinson E. A. , Silberberg V.
Published: May 2006

The reaction of sulfur trioxide with methanesulfonic acid has been studied by examination of the nuclear magnetic resonance (n.m.r.) and Raman spectra of solutions containing up to 0.8 stoichiometric mole fraction of SO3.At relatively low SO3 concentrations the polysulfonic acid CH3S2O6H is formed initially and reacts with excess methane sulfonic acid to give methanesulfonic anhydride.[Formula: see text]CH3S2O6H and CH3SO3H exchange protons and SO3 rapidly and a single methyl resonance peak only is observed for these species in the n.m.r. spectrum. A separate methyl resonance is observed for (CH3)2S2O5 at relatively low concentrations of SO3, but at higher concentrations the peak merges with that due to CH3SO3H and CH3S2O6H because of the rapid equilibration of (CH3)2S2O5 with H2S2O7.[Formula: see text]At higher concentrations of SO3 it is likely that the system contains polymers of the three series CH3Sn+1O3n+3H, (CH3)2Sn+2O3n+5, and H2Sn+1O3n+4 in rapid equilibrium. Free SO3 is not found in the system at concentrations less than 60 mole %.
IONIZATION POTENTIALS OF ALKYL FREE RADICALS AND n-ALKANES THROUGH C17H36 BY ENERGY-CALIBRATED MOLECULAR ORBITAL METHODS
Authors: Melton Charles E. , Joy Hubert W.
Published: May 2006

Ionization potentials are calculated by simple energy-calibrated molecular orbital techniques for the normal alkanes through C17H36 and for some normal and branched alkyl free radicals. A model is formulated which allows the computations to be extended to extremely large molecules by using "radical" orbitals as well as atomic orbitals in the expansion scheme. Auto-ionization levels as well as ionization potentials are calculated for the radicals. Computed and observed values are in good agreement where recent experimental data are available.
DECARBOXYLATION OF STRONG ACIDS BY METAL ACETYLACETONATES
Authors: Fetter Neil R.
Published: May 2006

not available
THE TRANSMISSION OF POLAR EFFECTS: IV. THE KINETICS OF ESTERIFICATION WITH DIAZODIPHENYLMETHANE OF SUBSTITUTED HETEROCYCLIC CARBOXYLIC ACIDS
Authors: Bowden Keith , Parkin D. C.
Published: May 2006

The rate coefficients for the reaction with diazodiphenylmethane, in ethanol at 30.0°, of a number of substituted indole-2-carboxylic acids, indole-3-carboxylic acids, coumarin-3-carboxylic acids, coumarilic acids, and N-phenylglycines have been determined. The effect of substitution is assessed by use of adapted Hammett and Dewar–Grisdale relations. The relations give good correlations for oxygen-ring heterocyclic systems, and the relative ability of the systems to transmit π-electron effects has been determined. An anomalous perturbing effect appears to operate in the indole-carboxylic acid systems.
LIGNANS OF WESTERN RED CEDAR (THUJA PLICATA DONN): IV. THUJAPLICATIN AND THUJAPLICATIN METHYL ETHER
Authors: MacLean Harold , Murakami Koji
Published: May 2006

In addition to the already known plicatic acid and plicatin, five new lignans have been separated by thin-layer and column chromatography from the hot-water extractive of western red cedar (Thujaplicata Donn) heartwood, and two chemical structures have been identified. These are 2-(4″-hydroxy-3″,5″-dimethoxybenzyl)-3-(4′-hydroxy-3′-methoxybenzyl)-butyrolactone (thujaplicatin methyl ether) (I) and 2-(3″,4″-dihydroxy-5″-methoxybenzyl)-3-(4′-hydroxy-3′-methoxybenzyl)-butyrolactone (thujaplicatin) (II). The former is the first known example of a lignan containing a guaiacyl and a syringyl nucleus and the first example of a syringyl-group lignan isolated from a conifer. Proof of structure by synthesis, degradation, analysis, and various spectra is presented. The other components which apparently belong to this lignan series are still being investigated.
THE PHOTOINITIATED HALOGENATION REACTIONS OF N-BROMOACETANILIDE AND N-BROMO-2,4,6-TRICHLOROACETANILIDE
Authors: Tanner Dennis D. , Protz Eugene
Published: May 2006

The photoinduced rearrangement reaction of N-bromoacetanilide to p-bromoacetanilide in carbon tetrachloride was found to have a quantum efficiency approaching unity, and evidence is presented to indicate a chain component to the reaction process whose product-determining species is either the mesomeric acetanilide radical or the bromine atom. It was demonstrated that small variations in the solvent composition affected the product ratio of p- to o-bromoacetanilide. The reaction of N-bromoacetanilide in carbon tetrachloride with added toluene was found to be a long-chain process producing p-bromoacetanilide as well as acetanilide and benzyl bromide. The bromination of toluene by N-bromo-2,4,6-trichloroacetanilide was shown to proceed by a chain mechanism involving the bromine radical as the chain-propagating species, and this mechanism is used as a model to explain the reaction of N-bromoacetanilide in dilute carbon tetrachloride solutions of toluene.
2-ALKOXY-3-HYDROXYTETRAHYDROPYRANS AND 2-ALKOXY-3-HYDROXYTETRAHYDROFURANS: I. PREPARATION, STRUCTURE, AND SOME DERIVATIVES
Authors: Sweet F. , Brown R. K.
Published: May 2006

Oxidation of 2,3-dihydrofuran or 2,3-dihydropyran with peroxybenzoic acid or m-chloroperoxybenzoic acid in the presence of an alcohol has produced, respectively, trans-2-alkoxy-3-hydroxytetrahydrofurans in 59 to 64% yield and trans-2-alkoxy-3-hydroxytetrahydropyrans in 65 to 80% yield. In the presence of acids, these acetals isomerize readily to give an equilibrated mixture of cis and trans isomers.
AMÉLIORATION DE LA SYNTHÈSE DES DI- ET TRI-BROMHYDRINES DU PENTAÉRYTHRITOL
Authors: Saucier M. , Sauriol C. , Salvador R. L.
Published: May 2006

not available
PYROLYSIS OF DIMETHYLETHANOLAMINE OXIDE MONOHYDRATE
Authors: Shulman Garson P.
Published: May 2006

not available
CHÉLATES DU GERMANIUM (IV) AVEC LA TROPOLONE, LE MALTOL, LA LAWSONE ET LA TRICHLOROHYDROXY p-BENZOQUINON E: I. PROPRIÉTÉS ACIDES-BASES DES α-HYDROXYCÉTONES
Authors: Beauchamp A. , Benoit R. L.
Published: May 2006

The acidity constants k1 of the following α-hydroxyketones HL tropolone, maltol, lawsone, and trichlorohydroxy p-benzoquinone have been determined at ionic strength 0.50 (HCl, NaCl)• The values of pk1 are respectively: 6.67 ± 0.04; 8.36 ± 0.03; 4.00 ± 0.04; 1.05 ± 0.04. The formation of conjugated acids H2L+ in strongly acidic media has also been studied. The values of pk2 defined in terms of the acidity function H0 are: −0.53 ± 0.10; −0.71 ± 0.10; −5.6 ± 0.2; −8.8 ± 1.0.
AROMATIC SUBSTITUTION: XIV. THE HOMOLYTIC PHENYLATION OF 3- AND 4-PICOLINE. A QUANTITATIVE STUDY OF ISOMER AND TOTAL RATE RATIOS
Authors: Abramovitch R. A. , Saha Maitreyi
Published: May 2006

The homolytic phenylation of 3- and 4-picoline under the conditions of the Gomberg–Hey reaction has been studied quantitatively. The methyl group in both picolines was found to activate the nucleus to the same extent. All the nuclear positions in both systems, except for C5 in 3-picoline, were slightly activated as compared with any one position in benzene. The significance of these results is discussed.
PREPARATION AND STEREOCHEMISTRY OF 1,2-O-(2′-HYDRO0XY-ETHYLIDENE)- AND 1,2-O-(HYDROXYISOPROPYLIDENE)-GLYCEROLS
Authors: Gorin P. A. J. , Ishikawa T.
Published: May 2006

The cis- and trans-isomers of 1,2-O-(2′-hydroxyethylidene)-glycerol (I and II) and 1,2-O-(hydroxyisopropylidene)-glycerol (V and VI) were prepared and their configurations assigned by stereospecific chemical synthesis. Equilibration of 1,2-O-(2′-cis-hydroxyethylidene)-L-glycerol (I) in acidified chloroform gave mainly 1,3-O-(2′-cis-hydroxyethylidene)-glycerol (III). In the 1,2-O-(hydroxyisopropylidene)-glycerol series, equilibration data and infrared absorption studies showed that hydrogen bonding of the O-(hydroxyisopropylidene) hydroxyl group was more pronounced in the cis-isomers.
ACID-CATALYZED REACTIONS OF VINYL COMPOUNDS: IV. MECHANISM OF FORMATION OF THE PRODUCTS OF THE REACTION OF VINYL ACETATE AND BENZENE
Authors: Pepper J. M. , Robinson B. P.
Published: May 2006

In part II of this series the isolation and identification of nine products from the reaction of vinyl acetate with benzene and aluminium chloride were described. This paper presents a discussion of the mechanism of formation of these compounds.A comparison of the aluminium chloride catalyzed reactions of benzene with vinyl acetate and ethyl acetate is described. The reaction with ethyl acetate gave all the monocyclic products obtained from the reaction involving vinyl acetate, as well as m-diethylbenzene. The ratio of the ortho and para isomers of ethylacetophenone is the same in both reactions, which suggests that the same acetylating species is involved. The fact that none of the three polycyclic products is obtained from the reaction involving ethyl acetate suggests that the vinyl moiety of the ester is involved in the formation of these compounds from vinyl acetate. The use of 14C-labelled vinyl acetate confirmed the fact that the synthesis of 9,10-dimethylanthracene involved only the vinyl part of the ester.A study of the reactions of ethyl acetate and vinyl acetate with aluminium chloride showed that ethyl chloride and vinyl chloride, respectively, may be intermediates in the alkylation of benzene with these reagents. Evidence is presented that 1-phenylethyl chloride may also be an intermediate product in the reaction of vinyl acetate and benzene. 1,1-Diphenylethane is believed to be involved in the formation of 9,10-dimethylanthracene, the final step of which is thought to occur by the dehydrogenation of 9,10-dihydro-9,10-dimethylanthracene.
PYRROLE CHEMISTRY: V. FRIEDEL–CRAFTS ISOPROPYLATIONS OF SOME PYRROLE DERIVATIVES
Authors: Anderson Hugh J. , Hopkins L. Cameron
Published: May 2006

The Friedel–Crafts isopropylations of methyl 2-pyrrolecarboxylate, 2-pyrrolecarboxaldehyde, and 2-pyrryl methyl ketone have been investigated under a variety of conditions. Products have been isolated and identified. The effects of different Lewis acid catalysts, solvents, and reaction times upon conversion and product isomer distribution have been determined. These results support the sequence of mechanistic steps suggested in an earlier publication. Further experiments have involved attempted rearrangements and disproportionations under alkylation conditions. The evidence indicates that Lewis acid complexing of the carbonyl oxygen deactivates position 4 in electrophilic substitution less than it does positions 3 and 5. The extent of deactivation of the different positions varies from 2-ester to 2-ketone to 2-aldehyde. Some proton nuclear magnetic resonance investigations of the Lewis acid complexes of these 2-carbonyl pyrroles are also reported.
LONG CARBON CHAIN CARBOHYDRATE POLYMERS: 1,3-(BIS-5-ALDOXYLOSYLIDENE-1)-ACETONE AND ITS POLYMER WITH 1,3-DICARBETHOXYACETONE
Authors: Papadakis Philippos E. , Philip S. M.
Published: May 2006

1,3-Dicarbethoxy-1,3-(bis-(4′,5′-O-isopropylidene-D-xylofuranosylidene))-acetone was hydrolyzed and decarboxylated to produce 1,3-(bis-D-xylofuranosylidene-5)-acetone (III) and 1,3-(bis-5-aldoxylosylidene-1)-acetone (IV). Compound IV reacted with 1,3-dicarbethoxyacetone in 75% methanol, with piperidine as catalyst, to give polymers V and VI and some intermediates. The main component of polymer V had a molecular weight between 2 000 and 4 000, and there were six to seven components with molecular weights of less than 2 000. Because the molecular weight of the repeating unit is approximately 500, a polymer with a molecular weight of 2 500 would have 80 carbons in a continuous chain, and one with a molecular weight of 3 500 would have 112 carbons. The work presented in this article may open broad areas of further research.
THE PHOTOLYSIS OF 4,4-DIMETHYLANDROST-5-EN-17β-OL-3-ONE
Authors: Taylor Ronald T. , Just George
Published: May 2006

The photolysis of 4,4-dimethylandrost-5-en-17β-ol-3-one (I) in aqueous tetrahydrofuran has been shown to give products of reduction, adducts with tetrahydrofuran, and 5-isopropyllactones VI and VII.
ORGANIC SULFUR MECHANISMS:5. PHOTOLYSIS OF UNSATURATED SULTAMS AND THE QUESTION OF ABNORMAL ADDITION TO SULFENES
Authors: Durst T. , King J. F.
Published: May 2006

not available
PYRANOSE–FURANOSE AND ANOMERIC EQUILIBRIA: INFLUENCE OF SOLVENT AND OF PARTIAL METHYLATION
Authors: Mackie W. , Perlin A. S.
Published: May 2006

Sugars possessing the arabino (2,3,4-trans,cis) configuration exist as furanoses to a greater extent in dimethyl sulfoxide than in water. Their 2,3-di-O-methyl derivatives show an even stronger preference for a five membered ring structure in both solvents. This is most marked for 2,3-di-O-methyl-D-arabinose and 2,3-di-O-methyl-D-altrose, which are 65% and 80% furanose, respectively, in dimethyl sulfoxide. Compounds in the xylo (2,3,4-trans,trans) or lyxo (2,3,4-cis,trans) series show little tendency to be furanoses in either solvent. However, α-pyranoses in the lyxo series are relatively more stable in dimethyl sulfoxide than in water, whereas the anomeric composition for members of the xylo series is the same in both solvents. Some of these variations in the equilibria are attributed to the preferential stabilization of pyranose forms in water. D-Lyxose and D-ribose show nuclear magnetic resonance spectral differences in the two solvents that appear to be due to conformational, as well as tautomeric, equilibrium changes.An equatorial anomeric hydroxyl proton of a given pair in dimethyl sulfoxide shows a larger spacing (6.5–8.0 c.p.s.) than an axial anomeric hydroxyl proton (4–5 c.p.s.). The signal for the latter proton occurs at higher field than an equatorial OH-1, except when OH-2 is axial.
THE BIOSYNTHESIS OF FUSARIC ACID FROM14C-LABELLED ACETATE IN GIBBERELLA FUJIKUROI
Authors: Hill R. D. , Unrau A. M. , Canvin D. T.
Published: May 2006

Acetate-1-14C and acetate-2-14C were supplied to cultures of Gibberellafujikuroi (Saw.) Wr., and the radioactive fusaric acid consequently formed was isolated. Acetate-1-14C contributed activity mainly to C-4, C-6, C-7, C-8, and C-10 of fusaric acid, whereas acetate-2-14C contributed activity to C-2, C-3, C-5, C-9, and C-11 of fusaric acid. These results are consistent with the hypothesis that fusaric acid is formed from a polyacetate unit and aspartic acid or closely related metabolites.
REACTION OF SODIUM o-NITROPHENOLATES WITH ETHYL 2-BROMO-2-CYANOACETATE
Authors: Coutts R. T. , Hindmarsh K. W.
Published: May 2006

not available
α-NEROL AND α-GERANIOL
Authors: Mitzner Bernard M. , Mancini Vito J. , Lemberg Seymour
Published: May 2006

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TREIBS' 119° GLYCOL; TRANSANNULAR ATTACK AT THE TERTIARY CARBON OF A SECONDARY–TERTIARY EPOXIDE
Authors: Warnhoff E. W. , Srinivasan V.
Published: May 2006

The glycol, C15H26O3, of m.p. 119° formed in the oxidation of caryophyllene oxide (I) has been found to have the structure and stereochemistry IVa formed by intramolecular transannular displacement at the tertiary carbon of the secondary–tertiary oxide in III. A rationalization of this mode of attack is offered. The glycol IVa has been transformed into the known keto epoxide XIIb obtained from isocaryophyllene.
THE STRUCTURES OF TWO SELF-CONDENSATION PRODUCTS FROM o-AMINOBENZALDEHYDE
Authors: McGeachin S. G.
Published: May 2006

The nature of two self-condensation products of o-aminobenzaldehyde (one a bisanhydro trimer and the other a trisanhydro tetramer) formed under different conditions of acid catalysis has been reexamined Spectroscopic evidence is presented to support the assignment of structures V (R = H) and VIII (R = R′ = H) to these.
A NOVEL SYNTHESIS OF SOME MIXED ARYLMETHYL–ALKYL ETHERS
Authors: Rutherford K. G. , Mamer O. A. , Prokipcak J. M. , Jobin R. A.
Published: May 2006

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POLYFLUORINATED AROMATIC ESTERS PREPARATION AND CARBONYL STRETCHING FREQUENCIES
Authors: Filler Robert , White James F. , Kacmarek Andrew J. , Solomon Irvine J.
Published: May 2006

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NOTE SUR LE CLIVAGE DE L'OZONIDE PRIMAIRE DU STYRÈNE
Authors: Fliszár S.
Published: May 2006

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EFFECT OF THERMIONIC EMISSION ON ELECTROCHEMICAL MEASUREMENTS AT HIGH TEMPERATURES
Authors: Whiteway S. G. , Masson C. R.
Published: May 2006

In the measurement of electromotive forces at temperatures over 1 000° spurious contact potentials, which may be asymmetric, are sometimes encountered. As an example of these, contact potentials between solid oxides and electrically grounded portions of their environment were measured at temperatures between 1 000° and 1 450°. Their variation with temperature, gaseous environment, and impedance of the measuring circuit is presented and interpreted in terms of thermionic emission.
THE INFRARED SPECTRUM AND THERMAL DECOMPOSITION OF HYDRAZINE PERCHLORATE HEMIHYDRATE
Authors: Jacobs P. W. M. , Russell-Jones A.
Published: May 2006

The infrared spectrum of hydrazine perchlorate hemihydrate (HPH) has been determined and an assignment of the absorption bands made. Invacuo, HPH will partially dehydrate even at room temperature; when heated the remainder of the half-mole of water is lost at 61 °C. The dehydrated salt melts at 138 °C and decomposition ensues. The kinetics of decomposition may be followed in the temperature range 180–280 °C. The activation energy is 36.3 kcal/mole. At low temperatures the decomposition is represented by the chemical equation[Formula: see text]but when the temperature is high enough the rate of decomposition of the ammonium perchlorate formed becomes appreciable also. Possible reaction mechanisms are discussed.