bluuebunny/crossref_metadata_2025_split huggingface dataset:
Etudes sur les matières végétales volatiles CXCIISur la composition des huiles essentielles d'ylang‐ylang
Authors: Naves Yves‐René , Ardizio Pierre 
Published: December 2004

AbstractThe ylang‐ylang oils «extra» «first» «second» and «third» have been analysed by vapor phase chromatography and compared with absolute oils described in 1959. The contents in geranyl acetate are far lower than advocated by KATAGUE&KIRCH.It is firmly established that the sesquiterpenes are artefacts, the findings of GLICHITCH&NAVES(1932)on the relative rates of distillation of benzyl benzoate and sesquiterpenes being confirmed.
Note sur la catalyse acide de la réaction des phosphobétaïnes avec le benzaldéhyde
Authors: Fliszár S. , Hudson R. F. , Salvadori G. 
Published: December 2004

AbstractThe catalysis by benzoic acid of the reaction between carbethoxymethylene‐tri‐phenylphosphorane and benzaldehyde, reported by KUCHARDT et al. for benzenic solutions, is reduced by changing the solvent from benzene to chloroform, and by increasing the temperature. These observations are interpreted by specific hydrogen bonding in the transition state, which also explains the lower activation energy of the reaction in chloroform.
Eine einfache neue Synthese für Säureanhydride
Authors: Rinderknecht Heinrich , Ma Victoria 
Published: December 2004

AbstractA novel method for the synthesis of acid anhydrides is described. Condensation of two molequivalents of a triethylammonium salt of an aliphatic or aromatic acid with one molequivalent of phosgene in an inert solvent at low temperature furnishes excellent yields of anhydrides.
Strahlungschemie von Kolhenwasserstoffen 10. Mitteilung Let‐Effekte in Toluol
Authors: Hoigné J. , Burns W. G. , Marsh W. R. , Gäumann T. 
Published: December 2004

AbstractLiquid toluene was irradiated with 60Co γ‐rays, with protons of energies from 1.8 down to 0.5 MeV and with α‐particles of 1.5 and 0.7 MeV with a dose of 10 and 30 Mrad at 20‐25°C. The G‐values increased with increasing LET from 0.11 to 0.58 for hydrogen, from 0.95 to 1.55 for polymers, from 0.055 to 0.061 for bibenzyl, from 0.034 to 0.042 for bitolyls, 0.020 to 0.066 for benzyltoluene and 0.028 to 0.051 for benzyldihydrotoluene. The isomer ratio of the six bitolyls changed appreciably but the ratio of the three benzyltoluenes remained constant. The yield vs. LET dependence shows different characteristics for the different products formed. The competition of reactions of first and second order with respect to primary reactive species are discussed. The results approve the hypothesis that benzyltoluene is mainly formed by a second order reaction of reactive primary particles in the spurs. If this molecule formation would be due to a radical recombination, then a small spur‐radius must be accepted for this reaction.
Anorganische Dünnschicht‐Chromatographie 9. Mitteilung Dünnschichtchromatographische Trennung von Sulfaten und Polythionaten
Authors: Seiler H. , Erlenmeyer H. 
Published: December 2004

AbstractThin laver chromatography is applied to the separation and identification of several oxoacids of sulfur and some polythionic acids.
Über die Hydroxidhalogenide Me2(OH)3Cl, ‐Br, ‐J zweiwertiger Metalle (Me = Mg, Ni, Co, Cu, Fe, Mn)
Authors: Oswald H. R. , Feitknecht W. 
Published: December 2004

AbstractThe preparations of the 3:1 hydroxide halides Me2(OH)3Cl, ‐Br and ‐I of Mg, Ni, Cu, Co, Fe and Mn are described, and the corresponding X‐ray data registered. The following structures were found: Layer structures: (a) C6 type [α‐Mg2(OH)3Cl, α‐ Ni2(OH)3CI, α‐Co2(OH)3Cl, α‐Fe2(OH)3CI, α‐Mn2(OH)3Cl]; (b) Botallackite type [α‐Cu2(OH)3Cl (= synth. Botallackite), Cu2(OH)3Br, Ni2(OH)3Br, α‐Co2(OH)3Br, Fe2(OH)3Br, Cu2(OH)3I, Ni2(OH)3I, Co2(OH)3I, Fe2(OH)3I, Mn2(OH)3I].
Synthèses d'analogues structuraux de l'élédoïsine. 2me partie: Préparation de tétrapeptides, pentapeptides et hexapeptides intermédiaires
Authors: Sandrin Ed. , Boissonnas R. A. 
Published: December 2004

AbstractThe preparation of new tetrapeptides, pentapeptides and hexapeptides, which constitute intermediates in the synthesis of Eledoisin analogues, is described.
Flavosemichinon‐Metallchelate: Modelle zur Erklärung der «active site» in den mitochondrialen Flavoenzymen. Zum Verhalten des Riboflavins gegen Metallionen III
Authors: Hemmerich P. 
Published: December 2004

AbstractThe behaviour of half reduced isoalloxazine (flavocoenzyme) systems, riboflavin and analogues, has been studied acidimetrically and spectrophotometrically in aqueous solution, in the presence or absence of non‐redox d‐metal ions. The metal has been found to combine selectively with the flavin semiquinone anion, forming deep red radical chelates with cornproportionation of the ligand system. Colour and reactivity of native metal‐containing flavoenzymes might be explained satisfactorily by this. Reference has been made to biological conclusions advanced elsewhere.
Les spectres de masse dans l'analyse. 3e communication. Les spectres de masse des hydrocarbures monoterpéniques
Authors: Thomas Alan F. , Willhalm B. 
Published: December 2004

AbstractThe mass spectra of cis‐ and trans‐p‐menthane, 5 menthenes, 5 saturated bicyclic hydrocarbons C10H18, and 22 terpenes C10H16 have been measured. Only the spectra of cis‐ and trans‐alloocimene were indistinguishable from one another; all the other substances gave specific fragmentation patterns that can be used in their identification.
Novobiocin V. Synthesen und Reaktionen von Acyl‐noviosylhalogeniden
Authors: Vaterlaus B. P. , Spiegelberg H. 
Published: December 2004

AbstractA number of arylglycusyl halides were synthesised and their usefulness for glycosidation with respect to synthesising novobiocin explored. The key intermediate, the 2,3‐O‐carbonyl‐noviosylchloride (10) is described.
Valenzisomerisierung und Fragmentierung von Cyclodecatertraenen. Cyclodecapolyene, 3. Mitteilung
Authors: Grob C. A. , Schiess P. W. 
Published: December 2004

AbstractDegradation of the N‐oxides and quaternary salts of the cis and trans forms of 1,6‐bis‐dimethylamino‐cyclodeca‐3,8‐dienes (4 b) and (4 c), respectively, afforded mixtures of hydrocarbons C10H12 separable by gas chromatography after hydro‐genation. In both cases a mixture of decalins, n‐butykyclohexane,n‐butylbenzene, cyclodecane and an unidentified tricyclic hydrocarbon C10H16 were obtained. However, COPE elimination yielded mainly trans‐decalin (66%), HOFMANN elimination mainly the cis isomer (58‐74%).
Photochemische Reaktionen. 26. Mitteilung. Zur UV.‐Bestrahlung von O‐Acety1‐1‐dehydro‐2‐methyl‐testosteron. (Vorläufige Mitteilung)
Authors: Ganter C. , Greuter F. , Kägi D. , Schaffner K. , Jeger O. 
Published: December 2004

AbstractThe ultra‐violet irradiation of O‐acetyl‐1‐dehydro‐2‐methyl‐testosterone (1) in dioxane solution leads to a mixture of ketonic and phenolic isomers from which five components (2–6) have been isolated. The structures of ketones 2 and 4 have been established. The sequence of photochemical rearrangements is1→2→3. Evidence points to the intermedi acyof an isomer of type e and the formation of compounds 4 and 5 from 3. Structural formulas for 3 (=g) and 5 (=j) are advanced on this basis. The close relationship between the sequences of rearrangements initiated by the irradiation of O‐acetyl‐1‐dehydro‐testosterone and its 2‐methyl homologue (1), respectively, is discussed.
Die Biosynthese des Digitoxigenins, Herkunft des C‐20. Glykoside und Aglykone, 253. Mitteilung
Authors: v. Euw J. , Reichstein T. 
Published: December 2004

AbstractMevalonic‐[3‐14C] acid (Ia) has been prepared by partial reduction of β‐hydroxy‐β‐methyl‐glutari‐[3‐14C] acid. After introduction of the ammonium salt of Ia into Digitalis lanata plants by the vick technique, crist. radioactive digitoxigenin was isolated. This contained a significant amount of radioactivity in C‐20 position. From this, together with results of former authors, it follows that the biosynthesis of digitoxigenin from mevalonic acid (probably via squalene) proceeds through a pregnane derivative. The latter needs only one molecule of acetate to form the butenolide ring.
Etude de l'évolution duméthyl‐2‐pentène‐2‐al et de l'éthyl‐2‐hexène‐2‐al en milieu aqueux alcalin à température élevée
Authors: Blanc Pierre Yves , Perret Adrien , Teppa Franco 
Published: December 2004

AbstractL'ensemble de nos résultats donne une image à peu prés complété de l'action de solutions aqueuses alcalines à env. 200° sur le méthyl‐2‐pentène‐2‐a1 et l'éthyl‐2‐hexène‐2‐al, qui grâce à la ramification de leur squelette carbonique en α, résistent à la résinification. II met clairement en évidence le rôle important de l'alcalinité dans leur évolution et la différence fondamentale de leur comportement par rapport à celui des aldéhydes non ramifiés ou saturés. En outre, nos recherches montrent que l'allongement de chaîne des aldéhydes tels que le propanal et le butanal, se fait par une voie qui n‵ést pas la méme A 200° qu'à 100°. A température peu élevé, c'est l'aldolisation multiple et linéaire de plusieurs molécules d'aldehyde initial qui est la rkgle [25].
Weitere Reaktionen an Acylchinonen und verwandten Verbindungen
Authors: Bosshard P. , Fumagalli S. , Good R. , Trueb W. , v. Philipsborn W. , Eugster C. H. 
Published: December 2004

AbstractEs werden die Synthesen von 3‐Acetyl‐5‐methoxy‐naphtochinon und 3‐Carb‐äthoxy‐5‐methoxy‐naphtochinon sowie deren Furanadditionsprodukte beschrieben. Nur das aktive 3,4‐Dimethoxyfuran addierte sich in nichtkatalysierter Reaktion. Es ist möglich, die Addition rnit Hilfe einer LEWIS‐Säure (z. B. ZnC12) zu fördern.
Structure de la carbamoyl‐benzamidoxime
Authors: Buyle R. , Lenaers R. , Eloy F. 
Published: December 2004

AbstractBenzamidoxime and cyanic acid react to give O‐carbamoyl‐benzamidoxime, and not the oxime of benzoylurea as generally admitted. 3‐Phenyl‐5‐hydroxy‐l,2,4‐oxa‐diazole is quantitatively formed by reacting hydroxylamine on carbamoylbenzami‐dine.
Metallionen‐Katalyse bei der H2O2‐ bzw. Radikalbildung durch autoxydable Cytostatica
Authors: Erlenmeyer H. , Zell R. , Brintzinger H. , Prijs B. 
Published: December 2004

AbstractThe formation of H2O2 during autoxydation of certain cytostatic agents like α‐aminoketones and methylhydrazine derivatives is shown to depend on the presence of metal ions. The biochemical implications of this finding, e.g. for the development of cytostatic tumor therapy and of appropriate tests are discussed.
Die Cardenolide der Samen von Strophanthus vanderijstii Staner. 3. Mitteilung. Identifizierung und Konstitutionsermittlung der wasserlöslichen Glykoside. Glykoside und Aglykone, 255, Mitteilung
Authors: Bernneisen K. , v. Euw J. , Tamm Ch. , Reichstein T. 
Published: December 2004

AbstractFive crystalline cardenolides (G, H, K, M1 and O‐acetyl‐M1) isolated from the seeds of Strophanthids vanderijstii could be identified with known glycosides. Probable structural formulae, based on results of enzymatic and chemical hydrolysis, were suggested for seven new cardenolides (M4, M5 O, P2 Q1 Q2 and Q3). Trivial names were given to two other new crystalline compounds, callengoside (J) and kisantoside (L1), which seem to be components characteristic of S. vanderijstii. Their structure is still unknown, each may contain a new genin. Both contain digitalose, and kisan‐toside perhaps an additional unit of hexose.
Dosage ampérométrique rapide, en une seule opération et sans séparation, du calcium et du magnésium dans le sérum sanguin et dans l'urine
Authors: Monnier D. , Rouèche A. 
Published: December 2004

AbstractUn dosage ampérométrique simple (réalisé en une seule opération) et trés rapide (25°) du Ca et de Mg dans le sérum, l'urine et les calculs est proposé. Le calcium est dosé par l'ion éthylheglycol‐bis‐(amino‐2‐éthyléther)‐N, N′‐tétracétate, et le magnésium, par l'ion éthyEnediamine‐tétracétate en présence d'un tampon (pH =10,5)et d'un complexant (citrate‐tartrate). Les courbes de polarisation montrent que le mercure est oxydé à 20 mV en présence d'EGTA ou d'EDTA. Le courant qui semanifeste dans ces conditions marque la fin des titrations. La précision est de ± 2,5%pour le Ca et ± 5,0% pour le Mg. Dans le cas de l'urine un traitement oxydant préalable est nécessaire (minéralisation complète ou traitement au KMnO4). La précision est de ± 5,0% pour les deux éléments.
Methylvinylfulvene
Authors: Neuenschwander M. , Meuche Doris , Schaltegger H. 
Published: December 2004

Abstract6‐ [l‐propenyl]‐fulvene (11), 6‐isopropenyl‐fulvene (111) and 6‐methyl‐vinyl‐ fulvene (IV) have been prepared by condensation of cyclopentadiene with trans‐ crotonaldehyde, methacrolein and methyl vinyl ketone, using sodium ethylate as base. The UV.‐, 1R.‐ and NMR.‐spectra have been investigated.
Weitere Alkaloide aus den Blättern von Pleiocarpa tubicina; Umwandlung von (—)‐Quebrachamin in (+)‐1,2‐Dehydroaspido‐spermidin 6. Mitteilung über Pleiocarpa‐Alkaloide [1]
Authors: Bycroft B. W. , Schumann D. , Patel M. B. , Schmid H. 
Published: December 2004

AbstractFrom the leaves of Pleiocarpa tubicina STAPF (+)‐Quebrachamine ((+)‐I), (−)‐1,2‐Dehydroaspidospermidine (( −)‐II), and (−)‐Aspidofractinine (IV), have been isolated in small quantities. The interesting conversion of (−)‐Quebrachamine ((−)‐I) into(+)‐1,2‐Dehydroaspidospemidine ((+)‐II) has been achieved by controlled per‐manganate oxidation.
Propriétés et structure de la cétolactone C12H16O3 de l'essence de Jasmin (Jasminum grandiflorum L.)
Authors: Demole E. , Willhalm B. , Stoll M. 
Published: December 2004

AbstractThe ketolactone C12H16O3 discovered by NAVES & GRAMPOLOFF [3] in 1942 in an Italian jasmine oil is shown to be the lactone IV of 2‐(5‐hydroxy‐cis‐pent‐2‐enyl)‐3‐oxo‐cyclopentylacetic or 5′‐hydroxy‐jasmonic acid (V ). Contrary to the findings of NAVES & GRAMPOLOFF, this hydroxy‐acid does not lactonize spontaneously, and the ketolactone IV has no odour.
Dibenzo‐azepine, ‐diazepine, ‐Oxazepine und ‐thiazepine. 3. Mitteilung über siebengliedrige Heterocyclen
Authors: Hunziker F. , Künzle F. , Schindler O. , Schmutz J. 
Published: December 2004

AbstractAn examination of the BISCHLER‐NAPIERALSKI reaction starting with 2‐acylamino‐diphenyl‐amines, ‐sulfides, ‐methanes, and ethers, resp., is reported. Using phosphorous oxychloride or polyphosphoric acid, the products are azomethine derivatives of 5H‐dibenzo[b, e]‐1,4‐diazepines, dibenzo[b, f]‐l,4‐thiazepines, llH‐dibenzo[b, e]‐azepines resp. dibenzo[b, f]‐l, 4‐oxazepines having the general formula III. The azomethine bridge in III can be hydrogenated catalytically or reduced with LiAlH4, to give derivatives of the general formula VI. Using several dialkylaminoalkyl chlorides in the presence of Na‐amide, these derivatives are alkylated to VII. The basic strengths of several derivatives of III and VI are reported and the correlation between the basicity and the heteroatom in III and VI is discussed. The thiazepine derivatives show a noticeably lowered basicity, which we could not explain either by the inductive or by mesomeric effects of the sulfur bridge‐atom.
Composés d'addition formés par le perchlorate d'argent avec des hydrocarbures aromatiques
Authors: Torre‐Mori B. G. , Janjic D. , Susz B. P. 
Published: December 2004

AbstractThe authors have prepared the 1 : 1 adducts between ‐AgClO4, and the hydrocarbons benzene, toluene and m‐xylene. The electronic absorption spectra of their solutions in the corresponding hydrocarbon exhibit each an absorption band between 2770 Å and 2900 Å. The same bands are found in solutions of AgClO4,in the hydrocarbons mentioned and in mesitylene.
Über Pyrrolizidinchemie 4. Mitteilung [1]Hydrierte Derivate des 2,5‐Dioxo‐3‐phenyl‐2,3‐dihydro‐5H‐pyrrolo[2,1‐a]isoindol‐1‐carbonsäure‐äthylesters
Authors: Viscontine M. , Pfenninger H. A. 
Published: December 2004

AbstractEin Dihydroalkohol und 4 stereoisomere Tetrahydroalkohole wurden nach NaBH,‐ oder katalytischer Reduktion des 2‐Hydroxy‐3‐phenyl‐5‐oxo‐SH‐pyrrolo[2,1‐a]isoindol‐l‐carbonsäure‐athylesters erhalten, isoliert und charakterisiert.Die Konfiguration der Tetrahydroalkohole ist noch nicht abgeklart.
Die STEVENS‐Umlagerung von Allyl‐phenacyl‐ammoniumsalzen
Authors: Heffe W. 
Published: December 2004

AbstractThe reported new examples of the STEVENS rearrangement of allyl‐ (or crotyl‐)phenacyl‐ammonium salts confirm that the allyl (or crotyl) group migrates rather than the phenacyl group, and that the migration of the crotyl group is accompanied by a shift of the double bond analogous to the shift in an allyl rearrangement.
Methämoglobinbildung in Erythrocyten durch Peroxideinwirkung. Versuche zur Beurteilung der Schutzfunktion von Katalase und Glutathionperoxidase
Authors: Aebi H. , Heiniger J. P. , Lauber E. 
Published: December 2004

Abstract
The rate of methaemoglobin formation induced by small amounts of H2O2, a) generated enzymatically, or (b) added by diffusion as vapour, has been investigated in suspensions of normal and acatalasic red cells.
At low rates of H2O2‐generation (i.e. 10−10−10−9 moles H2O2/mg Hgb/min) removal of H2O2 is mainly due to glutathione peroxidase activity, whereas at higher rates (i.e. 10−9−10−7 moles H2O2/mg Hgb/min) catalase activity is responsible for haemoglobin protection. Under the latter experimental conditions the yield of methaemoglobin formcd depends mainly on red cell catalase activity.
The existence of a lag‐phase in methaemoglobin formation and measurements of reduced glutathione concentration suggest that catalase and haemoglobin compete for excess H2O2 only after the intracellular supply of reduced glutathione has been exhausted and the H2O2 concentration in the cells has passed a critical level of than 7 · 10−6MH2O2.
«Tripeldecker‐Sandwiches» aus Ferrocen und Nickelocen
Authors: Schumacher Ernst , Taubenest Richard 
Published: December 2004

AbstractA mass‐spectrometric study of ferrocene and nickelocene revealed considerable intensities of ion‐molecule associates, e.g. Fe2Cp3⊕, Ni2Cp3⊕, and FeNiCp3⊕, which have not been found in an earlier investigation [l]. It is proposed that these particles represent tripel‐decker sandwiches.
Über die isomeren Dikobaltoctacarbonyle. III [1]. Infrarotspektren von Dikobaltoctacarbonyl, Quecksilber‐ und Cadmiumkobalcarbonyl bis 300 cm −1 und die Struktur des brückenlosen Dikobaltoctacarbonyls
Authors: Noack K. 
Published: December 2004

AbstractThe study of the temperature effect on the infrared absorption of dicobaltoctacarbonyl, which has led to the discovery of a non bridged isomer, has been extended to 300 cm−1. In the spectrum of the non bridged form only two bands have been found in the range from 700 to 300 cm−1, as compared with 8 for the bridged form. This is taken as further evidence that the non bridged isomer has a structure with D3d‐symmetry. For comparison the spectra of mercury and cadmium cobaltcarbonyl were also measured and found in agreement with the previously established structure.
Note sur quelques monoesters des acides chlorométhane‐, méthane‐ et benzène‐phosphoniques
Authors: Cherbuliez Emile , Čolak‐Antić Sl. , Gowhari M. , Weber G. , Rabinowitz J. 
Published: December 2004

AbstractPolychloromethanephosphonic acid (a partial anhydride) is obtained by heating chloromethanephosphonic acid with its dichloride. Heated with alcohols, polychloromethanephosphonic acid yields the corresponding chloromethanephosphonic monoesters.
Reaktivität von Koordinationsverbindungen XII [1]. Einfluss verschiedener Liganden auf den Mechanismus der Cu2+‐Katalyersierten Autoxydation von o‐Phenylendiamin
Authors: Wüthrich K. , Fallab S. 
Published: December 2004

AbstractThe Cu2+‐catalyzed oxidation of o‐phenylenediaminc (H2B) by O2 is strongly influenced by different organic and inorgarnic ligands. While chelating agents, e. g. ethylenediamine and ethylenediamine tetraacetic acid, inhibit the catalysis by Cu2+, the reaction is accelerated under the influence of some monodentate ligands, e.g. C1−, Br−, NH3, pyridine and imidazolc (PYR). We have found that these latter ligands enable the cupric ion to react directly with H2B (I). The cuprous complex
equation image
formed in equilibrium is then reoxidized by O2 (II). The rate determining oxidation step (I) is much faster than any direct reaction between o‐phenylenediamine and O2 catalyzed by cupric ion.
Metallionen‐Katalyse bei der H2O2‐ bzw. Radikal‐Bildung durch autoxydable Cytostatica. III. Ligand‐Effekte
Authors: Brintzinger H. , Zell R. , Erlenmeyer H. 
Published: December 2004

AbstractThe effect of various ligands on Mn2+‐catalysed radical and H2O2, formation by autoxidation of cytostatic hydrazine derivatives has been investigated. The catalytic action is activated by ligands which favour formation of the tervalent state of manganese ion. This finding is discussed in terms of possible mechanisms.
Recherches sur la formation et la transformation des esters LIII [1] Monoesters phosphoreux d'alcools tertiaires et de phénols
Authors: Cherbuliez Emile , Prince R. , Rabinowitz J. 
Published: December 2004

AbstractPhosphorous acid does not dehydrate tertiary alcohols at temperatures below 100 °C; but the esterification reaction is very slow and phosphorous monoesters of tertiary alcohols cannot be obtained this way. Although this reaction is also slow with phenol, phenyl phosphorous monoester can be obtained by heating 1 mole of phenol and 1 mole of H3PO3 4 days at 145°, with 15‐20% yield.
Was sind Elektronen??
Authors: Primas H. 
Published: December 2004

AbstractElektronen sind in der Quantenmechanik nicht‐individuelle, substanzlose Strukturen; in der klassischen Chemie sind sie dagegen individuell und lokalisiert. Es wird darauf hingewiesen, dass der mathematisch exakt definierte Begriff des Quasielektrons im Sinne der GREEN‐Funktion der modernen Quantenmechanik genau dem vom Che‐ miker intuitiv postulierten Elektronenbegriff entspricht; damit eröffnet sich die Möglichkeit einer exakten und dennoch anschaulichen Beschreibung der Molekeln. Bisher operationell nicht erklärte Probleme können damit zu echten naturwissenschaftlichen Fragen werden.
Die ESR.‐Spektren der Radikal‐Anionen des Hexamethylund des Hexaäthylradialens
Authors: Gerson F. 
Published: December 2004

AbstractRadical anions formed by alkali metal reduction from hexamethyl‐ and hexa‐ethyl‐radialene in 1, 2‐dimcthoxyethane solution are found to be relatively stable at temperatures below −20°C. The ESR.‐spectra of the radical anions have been recorded and their hyperfine structures discussed.
Eine Neuaufnahme* der ESR.‐Spektren der Radikal‐Anionen symmetrisch substituierter Dimethylnaphtaline
Authors: Gerson F. , Weidmann B. , Heilbronner E. 
Published: December 2004

AbstractESR. spectra of the radical anions of the six symetrically substituted dimethyl‐naphtalenes have been recorded. The methyl proton coupling constants show a close correlation with HÜCKEL spin densities (unpaired electron densities) if the inductive effect of the methyl groups is taken into consideration.
Zur Kenntnis der sogenannten «Alkalicarbonyle» VI Über den paramagnetischen Anteil der «Alkalicarbonyle»
Authors: Büchner W. , Lucken E. A. C. 
Published: December 2004

AbstractThe solid compounds resulting from the reaction between carbon monoxide and potassium, either molten or dissolved in liquid ammonia, have been shown by EPR. spectroscopy to contain low concentrations of free radicals. These solids dissolve in water to give deeply coloured solutions which also display EPR. spectra. It has been shown that the radical in the product formed from molten potassium at 250°C is mainly the potassium salt of tetrahydroxybenzosemiquinone, while the product from either molten potassium at 70°C or potassium dissolved in liquid ammonia contains at least two radicals. From the measurements made on the aqueous solutions, one of these has been shown to be the potassium salt of 2,5‐dihydroxy‐1,4‐benzosemiquinone. The other radical is thermally instable and is probably a non‐linear open‐chain radical. Dihydroxybenzoquinone seems to be formed during the removal of the ammonia.