bluuebunny/crossref_metadata_2025 huggingface dataset:
Lichtabsorption und Struktur von Kristallverbindungen der Übergangsmetalle. II. Lichtabsorption und Struktur der Halogenide, des Hydroxids und der Hydroxidhalogenide von Kupfer
Authors: Ludi A. , Feitknecht W.
Published: December 2004

The light absorption of the compounds CuX2 (X=Br, C1, F, OH), CuOHX (X=C1, F) and Cu2(OH)3X (X=J, Br, C1, F) has been measured by means of the reflection spectra. All the compounds investigated show the coordination 4+2, the coordination symmetry being either tetragonal or orthorhombic, according to the JAHN‐TELLER theorem. Due to this lower symmetry of the crystal field the 2D level is split into four levels. The absorption spectra consist of one broad band which can be resolved into two or three bands according to the degree of the tetragonal deformation. The spectrochemical series is found to be Br, F, C1, H2O, OH. In the case of the isostructural compounds Cu2(OH)3X (X=I, Br, C1) the influence of the halogenide does not show up in the absorption spectrum. The center of gravity of the main absorption band is located at 12000 cm−l for each of these compounds.
Tieftemperatur ‐ Elektronspinresonanz‐Spektren der Anionen des Cycl[3,2,2]azins und des 1,4‐Dideutero‐cycl[3,2,2]azins
Authors: Gerson F. , van Voorst J. D. W.
Published: December 2004

The electron spin resonance spectrum of the mononegative radical ion of cycl‐[3,2,2]azine has been measured under conditions in which ionic association is negligible. Some of the apparent degeneracies observed previously were due to overlapping of lines and have been removed by improving the resolution.
Herstellung der optisch aktiven Methyl‐benzyloxy‐malonsäurehalbester und Bestimmung ihrer absoluten Konfiguration. 57. Mitteilung über Mutterkornalkaloide
Authors: Stadler P. A. , Frey A. J. , Hofmann A.
Published: December 2004

The synthesis is described of the monoethyl ester chlorides of (S)‐ and (R)‐methyl benzyloxy malonic acid which are intermediates in the synthesis of ergotamine. Their absolute configuration was determined by linking the levorotatory antipode with S‐(+)‐citramalic acid.
Beiträge zur Chemie der pflanzlichen Plastiden. 3. Mitteilung. Über das Vorkommen von Lutein‐3‐linolenat in gelben Herbstblättern von Acer platanoides (L.)
Authors: Eichenberger W. , Grob E. C.
Published: December 2004

Unter den Carotinoiden gelber Herbstblätter von Acer platanoides wurde Lutein‐3‐linolenat gefunden. Die Stellung der Estergruppe wurde durch Veratherung der noch freien allylstandigen Hydroxylgruppe nach GROB & PFLUGSHAUPT bestimmt. Die Säurekomponente wurde in Form des Methylesters gas‐chromatographisch identifiziert. Es bestehen gute Hinweise dafür, dass in diesen Herbstblättern auch ein Lutein‐3′‐ester zugegen ist, dessen Fettsaurekomponente allerdings noch nicht bekannt ist.
Reaktionen mit Mikroorganismen. 12. Mitteilung. Die Stereospezifizität der Reduktion der Doppelbindung in (±)‐Δ4‐9‐Methyl‐octalindion‐(3,8) mit Curvularia falcata
Authors: Acklin W. , Prelog V. , Serdarević B.
Published: December 2004

The constitution and configuration II has been determined for a saturated hydroxy ketone obtained earlier as a byproduct of the reduction of (±)‐Δ4‐9‐methyl‐octalin‐3,8‐dione by the microorganism Curvularia falcata.
Note sur les anhydrides et monoesters méthanephosphoniques et dodécanephosphoniques
Authors: Cherbuliez Emile , Weber G. , Rabinowitz J.
Published: December 2004

The preparation of methanephosphonic oxide and dodecanephosphonic oxide is described.
Recherches sur la formation etla transformation des esters XLVII. Sur les monoesters de divers acides du phosphore et sur leur vitesse de scission à différents pH
Authors: Cherbuliez Emile , Weber G. , Rabinowitz J.
Published: December 2004

Tetracoordinated acids of phosphorus (acids of type A) where the P atom is bonded to 4 O, or to 3 O and 1 C, are not esterificd when heated with alcohols.
Photochemische Reaktionen. 33. Mitteilung. Die Photoisomerisierung von 3‐Oxo‐Δ1;4‐Steroiden in Dioxanlösung Strukturaufklärung der Photoisomeren und Bestimmung der Umlagerungs‐Sequenzen
Authors: Frei J. , Ganter C. , Kägi D. , Kocsis K. , Miljković M. , Siewinski A. , Wenger R. , Schaffner K. , Jeger O.
Published: December 2004

The photo‐induced formation of ketonic and phenolic isomers from O‐acetyl‐1‐dehydro‐testosterone (1a) and from its 4‐methyl homologue 1d in dioxane solution has been described earlier [8][9][13]. The present paper summarizes the findings which resulted in the course of further investigations, and which, in part, have been published in preliminary form [11][14] and in recent reviews [12]. This work includes the ultraviolet irradiation of dienone 1a, its 10α‐stereoisomer 2a, and its 1‐, 2‐ and 4‐methyl homologues 1b–d. A series of rearrangements occurred in each case, as shown in Charts 2, 3, and 19.
Contribution à l'étude d'un produit de β‐hydroxyéthylation du rutoside. Partie 1. Isolement et identification des constituants majeurs par chromatographie sur papier
Authors: Courbat P. , Favre J. , Guerne R. , Uhlmann G.
Published: December 2004

Les cinq constituants majeurs du mélange obtenu par hydroxyéthylation des fonctions phénoliques du rutoside selon [2], ont été isolés par chromatographie sur papier, et leurs proportions relatives, évaluées. La comparaison des Rt obtenus respectivement sur papier non traité, sur papiers tamponnés respectivement au borate et au phosphate, et sur papier imprégné de chlorure d'aluminium, de même que l'étude des RM ont permis d'attribuer une structure définie à deux de ces substances, alors qu'un choix restreint de structures peut être proposé pour les trois autres.
Die Neutrallipide aus Hirnen von Früh‐ und Neugeburten
Authors: Lesch Peter , Meier Sylvia , Bernhard Karl
Published: December 2004

Using already published methods, the authors have determined in eight brains of premature and seven brains of new‐born children: dry matter, total lipids, pure lipids, and acid and neutral lipids. The latter have been separated into cerebrosides, sphingomyelines, colamine cephalines, and lecithins.
Chinazoline und Benzodiazepine XXX Die Synthese von Tetrahydro‐isochino[2,1‐d] [1,4]‐benzodiazepin‐6(7H)‐onen
Authors: Müller M. , Zeller P.
Published: December 2004

Starting from 1‐aryl‐dihydroisoquinolines, new tetrahydroisoquinobenzodiazepines have been synthesized. The pharmacological investigation indicated some sedative, muscle relaxant and anticonvulsant properties similar to those encountered in known 1,4‐benzodiazepine derivatives.
Zusammensetzung der Neutrallipide und deren Fettsäuren aus Walhirnen. IV. Hirne von Delphinen (Delphinus delphis)
Authors: Bernhard Karl , Lesch Peter , Neuhaus‐Meier Sylvia
Published: December 2004

The total lipids from different regions of 6 dolphin brains were extracted and separated into individual fractions. The highest concentration of cerebrosides was found in the cerebral myelin and in the pons, the highest amount of lecithines in the cerebral cortex. After saponification of all fractions, the fatty acid composition was analysed by gas chromatography. The brain regions showed significant differences in relation to their origin.

In comparison to the human brain, the brain of the dolphin contains more lipids due to the higher concentration of glycerophosphatides, whereas the contents of sphingolipids are identical in both species.
Langsame Inversion am pyramidal gebundenen Stickstoff: Kristallstrukturanalyse des trans‐N‐Methoxy‐3, 3‐di‐methoxycarbonyl‐5‐cyan‐1, 2‐oxazolidins
Authors: Dobler M. , Dunitz J. D. , Hawley D. M.
Published: December 2004

Crystals of two interconvertible, diastereomeric N‐methoxy‐3, 3‐di‐methoxy‐carbonyl‐5‐cyano‐1, 2‐oxazolidines have been examined by X‐ray analysis. The lower melting isomer, m.p. 55°, is shown to have trans configuration of the methoxy and cyano substituents. Some features of the molecular topography are discussed.
Synthese und Kristallstruktur von Tetramethylammonium‐Sodalith
Authors: Baerlocher Ch. , Meier W. M.
Published: December 2004

Tetramethylammonium sodalite, a synthetic species of composition (CH3)4NAlSi5O12, has been obtained in good yield under hydrothermal conditions in the absence of metal cations. Its crystal structure has been determined using accurate powder data since single crystals could not be grown. The structure seems to be body‐centered cubic with a = 8.975 Å but the true symmetry is non‐cubic (probable space group I4). Each cage of the aluminosilicate framework contains one tetramethylammonium ion. The organic cation does not conform to the cubic symmetry of the ideal framework. The methyl groups point to oxygen atoms of the framework, and the short methyl‐oxygen distances of 3.06 Å indicate strong CH … O interaction.

The present results indicate beyond doubt that CH … O hydrogen bonding involving methyl groups can occur in silicates. This is of particular significance in zeolite chemistry and in the interpretation of interlayer distances in organic clay complexes.
Die Konstitution der Melodinus‐Alkaloide (+)‐Meloscin, (+)‐Epimeloscin und (+)‐Scandin. 1. Mitteilung über Alkaloide aus Melodinus scandens FORST
Authors: Bernauer Karl , Englert G. , Vetter W. , Weiss Ek.
Published: December 2004

For the alkaloids meloscine, epimeloscine and scandine, isolated from the Apocynacee Melodinus scandens FORST., the structures 1, 10 and 11, respectively, are deduced. Scandine is proved to possess the relative configuration as shown in 11 r. For meloscine and epimeloscine the relative configurations as depicted in 1 r and 10 r are discussed.
ESR‐Spektren von CuN4‐Chromophoren II: Komplexe mit Ammoniak, Äthylendiamin, Biguanid, N‐Trifluoracetimidoyl‐trifluoracetamidin, N‐Trichloracetimidoyl‐trichloracetamidin, Tetraaza‐undecan, Hexamethyl‐tetraaza‐cyclotetradecan und ‐cyclotetra decadien in Einkristallen
Authors: Schneider W. , Baccini P.
Published: December 2004

The ESR spectra of eight copper complexes with two groups of nitrogen ligands have been measured in the solid state. The first group includes the σ‐bonding ligands ammonia, ethylenediamine, 1,4,8,11‐tetraaza‐undecane, and the macrocyclic hexamethyl‐1,4,8,11‐tetraazacyclotetradecane of CURTIS. Ligands of the second group are biguanide, the CF3 and CCl3 derivatives of acetimidoyl‐acetamidine, and hexamethyl‐1, 4,8,11‐tetraazacyclotetradecadiene.

Single crystals of the parent PtII, NiII, or ZnII compounds were used as host lattices and magnetic diluents. The spectra of the chromophores CuN4, showing resolved hyperfine structure due to copper and nitrogen nuclear spins, are fitting a Spin‐Hamiltonian on the basis of virtual site symmetry D4h. The parameters g∥, g⟂, A∥, and A⟂ were used to derive delocalization coefficients in terms of the LCAO‐MO model introduced by MAKI and MCGARVEY. The comparative study clearly reveals that no reliable information on π‐bonding is provided by application of this model. The results on σ‐bonding ligands are particularly valuable in showing that the simple LCAO‐MO model cannot account for the attenuation of spin orbit coupling due to σ‐bonding in a physically meaningful way. Our results are qualitatively in agreement with AMMETER'S explanation of this phenomenon in terms of a virtual expansion of the d‐shell in antibonding orbitals.
Koordinationszahl und nephelauxetischer Effekt von Komplexen der Lanthaniden
Authors: Geier G. , Karlen U. , v. Zelewsky A.
Published: December 2004

The EuIIIEDTA complex exhibits a strong temperature dependence of its absorption band at 395 nm in dilute aqueous solution. Similar but much weaker effects can be observed in solutions of SmEDTA and GdEDTA, whereas EDTA complexes of the other lanthanide ions as well as the aquo ions of the whole series show no significant change of their absorption spectra in nation number along the series of the lanthanide EDTA complexes that takes place from Sm to Tb at room temperature. It can be concluded from the nephelauxetic effect that the coordination number decreases with increasing atomic number. The coordination numbers of the aquo ions are the same for all trivalent lanthanide ions in dilute solutions.
Allgemeine Säure‐Basen‐Katalyse der Monomethylol‐Bildung aus Harnstoff und Formaldehyd in Wasser
Authors: Glutz B. R. , Zollinger H.
Published: December 2004

The kinetics of the reaction of formaldehyde with urea in aqueous solutions was studied polarographically between pH 0.99 and 12.45 at 40°C.

The reaction is first order with respect to both reactants and is subject to general acid and base catalyses. The catalytic constants for 21 catalysts were determined.

The catalytic constants follow, in general, the BRÖNSTED relationship to the acidity and basicity constants, respectively, of the catalysts.

It is emphasized that, in contrast to recent statements by PETERSEN, mechanisms involving a series of bimolecular steps involving acid‐base pre‐equilibria or rate‐limiting proton transfers are incompatible with the experimental data. In the rate‐limiting transition state urea, formaldehyde, and the catalyst are present.

At pH‐values above 11, the CANNIZZARO reaction is competitive with the methylol formation.
Höhere, kondensierte Ringsysteme. 4. Mitteilung. Grosse Ringe der [2n]Metacyclophanreihe
Authors: Paioni R. , Jenny W.
Published: December 2004

[27] Metacyclophane, [29] metacyclophane, and [210] metacyclophane with a 50‐membered ring are isolated in the pure state from the crude product of a WURTZ reaction with m‐xylylene dibromide, thus providing for the first time a complete series of cyclophanes with two to ten sub‐units. The structure of the new ring systems is determined from their UV., IR., NMR. and mass spectra. The physical constants of these large carbocyclic systems are compared with those of the well‐known smaller metacyclophanes, particularly with respect to conformation.
Strahlungschemie von Kohlenwasserstoffen. 16. Mitteilung. Benzol‐Brombenzol
Authors: Siegrist Renato , Gämann Tino
Published: December 2004

The decrease of the concentration of bromobenzene and the formation of biphenyl and bromobiphenyl have been studied in the system benzene‐bromobenzene under the influence of γ‐rays. Bromobenzene is in competition with its own products for the reactive state of benzene or it can transfer its energy to its products. The rate of this transfer to decomposition is 74 l/Mol. With the help of additives it has been shown that they can act in two ways: firstly they compete with bromobenzene for an activated state of benzene in a reaction that does not depend on temperature. The nature of this activated state has not been determined. Secondly they scavenge phenyl radicals that have been formed in about 70% of the decomposed bromobenzene molecules. This yield depends slightly on temperature. The relative reactivities compared to bromobenzene for the first case and to benzene in the second have been determined as follows: naphthalene (0.6; 23); anthracene (5.8; 800); benzophenone (0.5; 17); cyclohexene (‐; 20); N2O (0.018; ‐); NO (1.7; 250); O2 (‐; 3400). Naphthacene in benzene is strongly decomposed in the presence of bromobenzene, but it also enhances the decomposition of the latter.
Katalyse der Reaktion von Thionylchlorid mit Trichloressigsäure
Authors: Konecny Jan
Published: December 2004

The reaction of thionyl chloride with trichloroacetic acid is catalyzed by tetraethylammonium chloride, and the rate is proportional to the concentration of the salt. The catalytic activities of tetraethylammonium chloride, pyridine hydrochloride and piperidine hydrochloride are in the ratio 1: 0.4: 0.3.
Etude phosphorimétrique des complexes de l'acide borique avec la benzoylacétone dans des glaces d'«éther diéthylique‐acide sulfurique concentré» à 77K
Authors: Marcantonatos M. , Gamba G. , Monnier D.
Published: December 2004

Boric acid‐benzoylacetone complexes, formed in concentrated sulfuric acid, are investigated phosphorimetrically after addition of ether to forme suitable glaces at 77K. Spectral, equilibrium and mean lifetime determinations establish the formation of two successif mononuclear complexes of stability β1 = 1.4 ± 0.1 ± 105 et β2 = 3.1 ± 0.3 ± 107. Structures, based on equilibrium and spectral data, are proposed. The applicability of phosphorimetry to complex formation studies and its advantages, in this case, over fluorimetry and colorimetry, are briefly discussed on the basis of results obtained in the present work.
Etudes sur les composés organométalliques. XI [1]. Action du tétrabutoxytitane sur des solutions de Grignard
Authors: Dubsky George Jon , Jacot‐Guillarmod André
Published: December 2004

The reaction of titanium tetra‐n‐butoxide with phenylmagnesium bromide inether has been investigated. The species (C6H5)2Mg in the Grignard reagent leads to (C6H5)4Ti, whereas the dimeric species (C6H5)2Mg · MgBr2 produces an insoluble complex mTi(OBu)4 · n[(C6H5)2Mg · MgBr2]. Applied to other Grignard reagents, the use of R2Mg allowed the preparation of tetrabenzyltitanium, tetracyclohexyltitanium and tetramethyltitanium. Cristalline (C6H5)4Ti and (C6H5CH2)4 Ti have been isolated.
Darstellung und Eigenschaften von Komplexen des Typs cis‐(RCN)3M(CO)3 (M = Cr, M, W)
Authors: Werner H. , Deckelmann K. , Schönenberger U.
Published: December 2004

Metal complexes of the type cis‐(RCN)3M(CO)3 (M = Cr, Mo, W) have been prepared by different methods starting with M(CO)6 or, more conveniently, with substituted derivatives of the metal hexacarbonyls. Infrared spectroscopic studies indicate that the strength of the nitrile‐to‐metal bond in cis‐(RCN)3M(CO)3 is only sligthly influenced by the R group. The chromium compounds cis‐(RCN)3Cr(CO)3 may be used as starting materials for the preparation of hexaalkylborazine‐chromium‐tricarbonyls.
Etude par spectrométrie de masse de l'ionisation de benzonitriles, de phénylacétonitriles et de N,N‐diméthylanilines substitués
Authors: Buchs Armand
Published: December 2004

Molecular ionization potentials for series of compounds of the type XC6H4CN, XC6H4CH2CN and XC6H4N(CH3)2 have been measured using the retarding potential difference technique (RPD. technique). The effect of the various substituents X is better correlated through the electrophilic Brown σp+ constants than through Hammett's σp values. No meta‐para orientation effect is observed. For all the disubstituted phenyl compounds studied, the effect of the second substituent is affected by the electron‐releasing power of the original substituent. Ionization potentials calculated by using the semi‐empirical method of equivalent orbitals are in good agreement with the experimental values.
Photochemische Umwandlungen. XXXVIII [1]. Synthese und Eigenschaften Methoxycarbonyl‐substituierter «Quadricyclanone»
Authors: Prinzbach H. , Rivier J. , Englert G.
Published: December 2004

The three methoxycarbonyl‐substituted quadricyclanones 7a, 7b and 7c have been synthesized in good to excellent yields. Some of their physical (UV., NMR.) and chemical properties (e.g. condensation and pyrolysis reactions) are discussed.
Steroide und Sexualhormone. 238. Mitteilung [1]. Die Synthese von 14βO, 18N‐Ep (oxyäthanoimino)‐Steroiden
Authors: Berner‐Fenz Frau L. , Berner H. , Graf W. , Wehrli H.
Published: December 2004

The synthesis of the title compound 3 is described. The reaction sequence will serve as a model for a partial synthesis of batrachotoxinin A (2).
Steroide und Sexualhormone. 240. Mitteilung [1]. Die Synthese von 3β‐Methoxy‐3α, 9α‐oxido‐11α,20ξ‐dihydroxy‐14βO,18N‐[ep(oxyäthano‐N‐methylimino)]‐5β,17α‐pregnan (3‐O‐Methyl‐17α,20ξ‐tetrahydrobatrachotoxinin A)
Authors: Graf W. , Berner H. , Berner‐Fenz Frau L. , Gössinger Frl. E. , Imhof R. , Wehrli H.
Published: December 2004

The synthesis of 3‐O‐methyl‐17α, 20ξ‐tetrahydrobatrachotoxinin A (4) is described.
Über die Bildung von 9‐Hydroxy‐10,12‐ und 13‐Hydroxy‐9,11‐octadecadiensäure durch «Lipoperoxidase» aus Cerealien. Vorläufige Mitteilung
Authors: Heimann W. , Schreier P.
Published: December 2004

Nach Inkubation der durch Soja‐Lipoxygenase (E. C. 1. 13. 1. 13) gebildeten Linolsäurehydroperoxide (LHPO) mit einem Hafer‐Acetontrockenpulver in Phosphatpuffer pH 7,0 (0,05M) wurden als Umsetzungsprodukte die beiden ungesättigten 9‐Hydroxy‐10, 12‐ und 13‐Hydroxy‐9, 11‐octadecadiensäuren erhalten. Diese Reaktion wurde durch Einsatz von radioaktiv markierten LHPO bestätigt. Nach vorheriger Hitzeinaktivierung blieb die Umsetzung aus. Die Identifizierung der Reaktionsprodukte erfolgte an Hand der Massenspektren nach Veresterung, katalytischer Hydrierung und Oxydation zu 9‐Oxo‐ bzw. 13‐Oxo‐stearinsäure‐methylester.
Crystal Structure of the Antibiotic Monensin Similarities and Differences between Free Acid and Metal Complex
Authors: Lutz W. K. , Winkler F. K. , Dunitz J. D.
Published: December 2004

The structure of monensin, C36H62O11, has been determined by X‐ray analysis of its crystalline monohydrate (orthorhombic, a = 15.15, b = 23.61, c = 10.65 Å, Z= 4, space group P212121). Phases were assigned by direct methods, making use of the ‘tangent formula’. Although the conformation of the free acid resembles that of the silver salt in being cyclic, there are differences in the hydrogen bonding pattern. These features are discussed in relation to the complexation of metal ions by monensin.
Über Oxidhydroxide des vierwertigen Mangans mit Schichtengitter. 3. Mitteilung. Reduktion von Mangan(III)‐manganat(IV) mit Zimtalkohol
Authors: Giovanoli R. , Feitknecht W. , Fischer F.
Published: December 2004

Manganese(III) manganate(IV), one of the synthetic varieties of the birnessite group, is readily reduced in xylene suspension by cinnamyl alcohol. At moderate temperatures, including room temperature, γ‐MnOOH (manganite) forms topotactically in extremely thin needles and is therefore easily overlooked in the X‐ray examination. At higher temperatures further reduction occurs (MnIII → MnII), and Mn3O4 (hausmannite) appears in comparatively large, equant cristallites which are less distinctly oriented. For comparison Na4Mn14O27, 9H2O, which has also been investigated, is much more stable than Mn7O13, 5H2O. The same holds for finely divided synthetic varieties of the birnessite group precipitated from KMnO4 solutions; by their behaviour they are related to Na4Mn14O27, 9H2O rather than to Mn7O13, 5 H2O which is consistent with their substantial alkaline ion content.

These results raise the question: is the so‐called ‘todorokite’ a pure crystal species. According to present data ‘todorokite’ could be regarded as a transition product, i.e. as half decomposed buserite admixed with birnessite and substantial amounts of manganite.
Etude de composés d'addition d'acides de Lewis XXXIII [1]. Résonance magnétique nucléaire de composés formés par des aldéhydes aliphatiques et aromatiques avec des accepteurs électroniques
Authors: Filippini Franchino , Susz B.‐P.
Published: December 2004

Complétant leur étude des spectres d'absorption IR. de composés d'addition d'aldéhydes avec des acides de Lewis, montrant que l'accepteur se fixe sur l'atome d'oxygène du groupe CHO, avec diminution du caractère de double liaison de CO, les auteurs ont enregistré le spectre de RMN. protonique de certains de ces composés, en solution 0,2M dans CH2Cl2. Pour les aldéhydes aliphatiques, la variation Δτ du déplacement chimique de l'atome H de CHO due à l'addition de l'accepteur est négative et de l'ordre de grandeur de −0,1 à−0,4 ppm, ce qui correspond à un certain déplacement électronique dans la direction H → C → O, particulièrement marqué pour Cl3CCHO · SbCl5 (δτ = −0,41 ppm). Pour le benzaldéhyde, en revanche, Δτ est plus proche de zéro ou même positif: le noyau aromatique forme réservoir d'électrons modérant le déplacement cité. En tenant compte encore de variations éventuelles des effects d'anisotropie du noyau aromatique et du groupe CO donneur, on peut expliquer les valeurs observées.
The Structures of Medium‐Ring Compounds. Part XVII. Crystal and molecular structures of cis‐cyclodecene. 1/2 AgNO3 and 1,1,4,4‐tetramethyl‐cis‐cyclodec‐7‐ene. 1/2 AgNO3
Authors: Ermer O. , Eser H. , Dunitz J. D.
Published: December 2004

The crystal structures of cis‐cyclodecene. 1/2 AgNO3 (monoclinic, a = 5.329, b=14.53, c=27.17 Å, β=92.02°, space group C 2/c) and of 1,1,4,4‐tetramethyl‐cis‐cyclodec‐7‐ene · 1/2 AgNO3 (orthorhombic, a=5.879, b=16.86, c=28.39 Å, space group C2221) have been determined. The relative arrangement of Ag+ cations, NO3− anions and cyclo‐olefin molecules are very similar in the two crystals, but the conformations of the ring skeletons are very different.
Structure of [4.4.4]propellane and [4.4.4]propellatriene by X‐ray Analysis
Authors: Ermer O. , Gerdil R. , Dunitz J. D.
Published: December 2004

The crystal structures of [4.4.4]propellane (monoclinic, a=12.053, b=7.832, c=13.001 Å, β=104.89°, space group C2/c, Z=4) and [4.4.4]propellatriene (monoclinic, a=7.876, b=12.651, c=13.164 Å, β=122.81°, space group P21/c,Z=4) have been determined by X‐ray analysis. In propellane the six‐membered rings are in the chair conformation, in propellatriene they adopt the ‘half‐chair’ conformation with a twofold axis passing through the centre of each double bond. In both cases the observed parameters correspond to virtual D3(32) molecular symmetry. Corrections have been applied for the effect of molecular libration. Strain‐minimization calculations based on semi‐empirical potential functions have been carried out and the molecular parameters so derived are compared with the experimental values.
Steroid Total Synthesis, Part III. 9β, 10α‐Testosterone
Authors: Saucy G. , Borer R.
Published: December 2004

The total synthesis of 9β, 10α‐testosterone via a BCD‐tricyclic intermediate is described. The latter compound – 17β‐hydroxy‐des‐A‐androst‐9‐en‐5‐one – was obtained in optically active form by our previously reported scheme, using an efficient resolution step early in the synthesis. New results regarding the asymmetric induction step are also discussed.
Composés d'addition des halogénures de niobium(V) et de tantale(V) IV. Stabilité relative des composés de chlorures avec quelques nitriles
Authors: Merbach A. , Bünzli J. C.
Published: December 2004

The relative stability constants of the adducts of MCl5 (M  Nb, Ta) with acetonitrile, halogenoacetonitriles, pivalonitrile, acrylonitrile and benzonitriles are determined in dilute solutions by NMR. methods. The stability of the adducts is controlled by inductive factors. Chemical shifts and analysis of the new compounds are reported.
Röntgen‐Kontrastmittel: (2,4,6‐Trijodbenzoyl)‐aminosäuren
Authors: Suter H. , Zutter H.
Published: December 2004

New N‐(3, 5 substituted 2,4,6‐triiodobenzoyl)‐amino acids have been synthesized as potential X‐ray contrast agents for chloecystography. Toxicity, bilitropism, urotropism, and cholecystographic quality of these compounds are given.
Photochemische Umwandlungen, 45. Mitteilung [1] die 3σ → 3π‐route zu oxepin‐derivaten
Authors: Eberbach W. , Perroud‐Argüelles M. , Achenbach H. , Druckrey E. , Prinzbach H.
Published: December 2004

Exemplifying with the 4.5‐dicarbomethoxy oxepin 6a the authors describe an oxepin synthesis from furanes and acetylenic dienophiles via Diels‐Alder reaction (4a), photochemical oxanorbornadiene‐oxaquadricyclane transformation (4a → 5a), and thermal 3σ → 3π opening of the highly strained oxaquadricyclane 5a. With dimethylacetylenedicarboxylate, methylpropiolate, maleic anhydride, and di‐methoxycarbonyl‐oxanorbornadiene (4a) 5a yields the 1:1 adducts 19a, 19b, 22, 23 and 26 (unstable) by strictly stereospecific addition to the α‐positions of the oxygen bridge. With the same dienophiles the oxepin 6a reacts only through its valence‐tautomeric benzene‐oxide form 7a giving stereospecifically 27, 29, 30 and 31. No definite conclusions are drawn with regard to the mechanistic implications of the photostep 4a → 5a, the thermal 3σ → 3π‐transformation 5a → 6a/7a, and the bishomofurane cycloaddition reactions. Scope and limitations of this oxepin synthesis are briefly discussed.
Equilibres conformationnels de glucides au niveau de liaisons σ sp2‐sp3 C‐C. III Dérivés d'oximes d'aldéhydo‐sucres utilisation de tris‐dipivaloylméthanato‐europium
Authors: Tronchet J. M. J. , Barbalat‐Rey F. , Le‐Hong N.
Published: December 2004

A series of sugar oximes and O‐methyloximes of the general formula RCHNOR′ (R′  H, CH3) have been studied by PMR. spectroscopy. These compounds exist in solution as a mixture of the syn and anti isomers. The conformational equilibrium of the syn isomers seems to consist exclusively of the eclipsed rotamers, whereas for the anti isomers there appears to be a significant contribution from bisecting rotamers. Using tris‐dipivaloylmethanato‐europium it is found that the α proton of the anti oximes is much more deshielded than the corresponding proton of the syn isomers, which means that the downfield shift of a particular proton does not depend exclusively on its distance from the oxygen of the oxyimino group.
Substituierte 9‐Oxabicyclo[4.2.1]‐ und 9‐Oxabicyclo[3.3.1]nonane III. neue ergiebige synthese von 2, 7‐dioxatwistan und endo‐2‐hydroxy‐9‐oxabicyclo[3.3.1]nonen‐(6)
Authors: Ganter C. , Zwahlen W.
Published: December 2004

Iodine cleavage of the [3.3.1]‐iodomercuri compound 4, easily prepared from cis, cis‐cyclooctadiene‐(1,5) by oxymercuration of the monoepoxide 1 (→ 3) followed by treatment with potassium iodide, leads to three isomeric iodides 6, 7, and 8, the [3.3.1]‐exo‐iodo isomer 8 being the predominant product.

Intramolecular substitution in 8 opens an attractive new route to unsubstituted 2,7‐dioxatwistane (19) [2], whereas dehydrohalogenation of 7 and 8 yields the unsaturated alcohol 17 [2], a suitable starting material for the preparation of substituted 2,7‐dioxatwistanes [2], 2,7‐dioxaisotwistanes (e) [2], and 2,8‐dioxa‐homotwistbrendanes (f).
Über den Verteilungssatz der Auxochrome bei Azokörpern IV Azokörper mit zueinander p‐ständigen Auxochromen
Authors: Kokkinos K. , Wizinger R.
Published: December 2004

In azo compounds with CH3O groups in o‐position to the azo groups the introduction of the weak auxochromes CH3– and CH3O– into the p‐position to the methoxy group (m‐position to the chromophor) causes relatively strong bathochromic effects, in conformity with the rule of repartition.
Die Synthese von überbrückten Cobaloximen
Authors: Rétey J.
Published: December 2004

Chloro‐pyridino‐bis (glyoximato)‐cobalt(III) complexes (cobaloximes) have been synthesized in which two corners are connected by a bridge consisting of 10 or 12 methylene groups. These compounds are designed to mimic some important features of the active site of coenzyme B12 dependent enzymes.
X‐Ray Analysis of a Bridged Cobaloxime (Chloro‐pyridino‐cis‐ 1,12‐bis‐methyglyoximato‐dodecane‐cobalt(III))
Authors: Bartlett M. W. , Dunitz J. D.
Published: December 2004

The structure of the title compound, a cobaloxime bridged by a polymethylene chain, has been confirmed by X‐ray analysis.
Protonierungs‐ und Deprotonierungskinetik des Systems Azulen‐Azuleniumkation, ein Beitrag zur Kenntnis der Hammett'schen Ho‐Aciditätsfunktion
Authors: Seiler P. , Werthemann D.
Published: December 2004

Using a flashphotolysis‐method to evaluate the rates of the protonation of azulene and the deprotonation of azuleniumcation as a function of H0 the validity of the Hammett H0‐function was examined. Using this technique it was possible to obtain information on the behaviour of the activity coefficients and to show that the Hc‐acidityfunction of Reagan [1] is a better measure of the hydrogen activity than the H0‐function. The dependence of the deprotonation rate on H0 is explained as a consequence of the different behaviour of the activity coefficients of Hammett‐indicators and azulene/azuleniumcation, respectively.
Structure of Brefeldin A
Authors: Weber H. P. , Hauser D. , Sigg H. P.
Published: December 2004

On the basis of X‐ray crystal structure analysis, CD. measurements, and asymmetric synthesis the absolute configuration of brefeldin A has been determined.
Steroide und Sexualhormone Die Partialsynthese von 3β‐Methoxy‐3α, 9α‐oxido‐7α‐hydroxy‐11α‐acetoxy‐5β‐steroiden
Authors: Imhof R. , Gössinger Frl. E. , Graf W. , Schnüriger W. , Wehrli H.
Published: December 2004

The preparation of the title compounds 11, 37, and 39 is described. 37 will serve as starting material for a partial synthesis of the steroidal alkaloid batrachotoxinin A (1).
Steroide und Sexualhormone 242. Mitteilung [1] herstellung von 14β‐hydroxy‐20‐keto‐δ16‐steroiden: Ein neuer ergiebiger zugang zu 3‐O‐methyl‐17α, 20ξ‐tetrahydrobatrachotoxinin A
Authors: Gössinger Frl. E. , Graf W. , Imhof R. , Wehrli H.
Published: December 2004

A novel method for the reductive epoxide opening in a 14β, 15β‐epoxy‐20‐oxo‐Δ16‐pregnene 4 affords an almost quantitative yield of the 14β‐hydroxy‐20‐oxo‐Δ16‐pregnene 5. This leads to a considerable improvement of the formerly published synthesis of 3‐O‐methyl 17 α, 20ξ‐tetrahydrobatrachotoxinin A (2) [3].
Nucleophile Substitution von Methyltosylat in dipolar aprotischen Lösungsmitteln
Authors: Müller Paul , Siegfried Bernard
Published: December 2004

The rate of the reaction between methyl tosylate and lithium bromide has been measured in various aprotic solvents. There is no simple correlation between rate and dielectric constant in aprotic solvents with low dielectric constant. In propylene carbonate the reaction is much slower than would be predicted on the basis of solvent activity coefficients. Solvation of substrate and transition state to play a role in determining the reaction rate in this solvent.
Die Phlorglucide von Dryopteris viliarii (Bell.) Woynar und anderer Farne der Gattung Dryopteris sowie die mögliche Abstammung von D. filix‐mas (L.) Schott
Authors: Widén C. J. , Vida G. , Von Euw J. , Reichstein T.
Published: December 2004

The phloroglucides of the ferns of the Dryopteris filix‐mas complex; i.e. D. abbreviata, D. filix‐mas s. str. and D. borreri (diploid and triploid) as well as those of D. villarii, subspvillarii and subsp. pallida were reinvestigated with improved semiquantitative analytical methods. The phloroglucides of D. aitoniana and D. athamantica were examined for the first time.

The results (table 1) are compatible with the hypothesis, without proving it, that the allotetraploid species D. filix‐mas s. str. originated from a hybrid of D. abbreviata with D. villard (with subsequent doubling of its chromosomes) and the apogamous triploid D. remota from D. assimils with diploid D. borreri, and the equally apogamous triploid D. borreri from a hybrid of D. abbreviata (or a related diploid sexual taxon) with diploid D. borreri.

D. aitoniana contains a large amount of trisflavaspidic acid but no filixic acid and differs in this respect from the three representatives of the D. filix‐mas complex.
Die Massenspektren von dreikernigen pflanzlichen Phlorogluciden
Authors: Lounasmaa M. , Widén C.‐J. , Reichstein T.
Published: December 2004

The mass spectra of four naturally occurring tricyclic phloroglucinol derivatives are presented. Molecular ion peaks are visible in all cases and most of the fragments can be understood by assuming that a cleavage of a methylene bridge occurs with the transfer of a hydrogen atom from a hydroxyl group, located ortho to the bridge, to the adjacent ring. This fragmentation pattern is analogous to that found earlier in bicyclic phloroglucinol derivatives [2]. Some other important peaks can only be rationalized by assuming that two types of thermal rottlerone rearrangements [3]‐[5] are occurring simultaneously: 1. Disproportionation of terminal intermolecular exchange; 2. Elimination of the middle ring, thus forming a bicyclic compound from two terminal rings.
Stereochemie der Ringöffnung der σ‐Komplexe von 2‐Naphtol‐1‐sulfonsäure mit Diazoniumsalzen und der anschliessenden Phtalazinbildung: Eine fragmentierung als konkurrenzreaktion der abspaltung der abgangsgruppe bei der elektrophilen substitution 25. Mitteilung zur Kenntnis der Azokupplung
Authors: Jaecklin A. P. , Skrabal P. , Zollinger H.
Published: December 2004

The reaction of 2‐naphthol‐1‐sulfonic acid with diazonium salts was investigated in the pH range 10 to 15. The structures postulated for the reaction products by Rowe et al. [3] and by Koller [4] were proved by instrumental analysis. In alkaline solutions, instead of the usual diazodesulfonation reaction, addition of an hydroxyl ion to the σ‐complex formed from 2‐naphthol‐l‐ sulfonic acid and substituted diazonium salts takes place. The resulting intermediates undergo heterolytic fragmentation leading to substituted o‐(phenylhydrazono‐sulfo‐methy1)‐cinnamicacids 7. The kinetic measurements prove that one equivalent of water is added during this fragmentation. 7 is produced by a conrotatory ringopening of the σ‐complex. An intramolecular ring closure in the formation of 8 from 7, results from studies of NMR. spectra, and molecular models show that both exocyclic double bonds in 7 have cis‐configuration. Kinetic measurements demonstrate that it is the anion 11 which enters the ring closure reaction: After intramolecular nucleophilic attack of the anionic nitrogen upon the double bond of the cinnamic group, a proton is added stereospecifically. The fragmentation of the σ‐complex is a competitive reaction to the release of the elctrofngal leaving group in electrophilic aromatic substitution. The fragmentation is dominant in this case because the electrofugal leaving group is not a proton but a SO, molecule. The conditions (constitution of reagents, catalysts, etc.) which influence the ratio of the two competitive reactions of cyclohexadienone‐type σ‐complexes are discussed.
10(5→4)‐abeo‐Corticosteroide. Über Steroide, 224. Mitteilung
Authors: Meystre Ch. , Schmidlin J. , Ueberwasser H. , Kaufmann H. , Anner G.
Published: December 2004

The synthesis of a new class of corticosteroids with rings A and B rearranged to a 10 (5→4)‐abeo system is reported. New methods are presented for the preparation and hydrolysis of corticosteroid derivatives, side‐chain‐protected by bis‐methylenedioxy groups, used as intermediates in some of the examples given.
Voacanǵa‐Alkaloide VII. Desoxovobasin
Authors: Jaeggi K. A. , Renner U.
Published: December 2004

Acidic cleavage of vacamine under reductive conditions yields desoxovobasine which was correlated with a product obtained by C(3)‐N fission of macusine B. Desoxovobasine can be transformed into indoline derivatives of a novel polycyclic system which has not yet been found among the naturally occurring indole alkaloids.
Stoffwechselprodukte von Mikroorganismen. 103. Mitteilung [1]. Zur Stereochemie des Lankamycins
Authors: Muntwyler R. , Keller‐Schierlein W.
Published: December 2004

The stereochemical structure of the macrolide antibiotic lankamycin could be completed by an extended NMR.‐analysis of the degradation products III, IV, VI and VIII.
Strukturaufklärung organischer Verbindungen durch computerunterstützten Vergleich spektraler Daten
Authors: Erni F. , Clerc J. T.
Published: December 2004

A system for computer‐aided identification of organic compounds by means of spectroscopic data is described. The binary coded spectral data of the unknown compounds are compared with a reference file containing NMR., IR. and Mass Spectra. A highly flexible software automatically selects the appropriate search strategy and directs the updating of the collection, thereby ensuring continuous adaption to varying needs.
Der zweistufige Carbanion‐Mechanismus der Fragmentierung von 3‐Aminopropylbenzoaten. Fragmentierungs‐Reaktionen. 25. Mitteilung
Authors: Grob C. A. , Unger F. M. , Weiler E. D. , Weiss A.
Published: December 2004

The unsubstituted and p‐substituted benzoates 2b–2e of 3‐dimethylamino‐2,2bis(p‐nitrophenyl)‐propanol (2a) undergo quantitative fragmentation in 80% ethanol yielding 1,1‐bis(p‐nitrophenyl)‐ethylene (5) besides formaldehyde and dimethylamine, the hydrolysis products of the imonium ion 3. The corresponding alcohol 2a, however, yields 2,2‐bis(p‐nitrophenyl)‐ethanol (9) in addition to fragmentation products. Conversely, no fragmentation is observed with the benzoates 6b–6e of 3‐dimethylamino‐2,2‐diphenylpropanol (6a) which lack electronwithdrawing substituents in the β‐phenyl groups.

These results are in agreement with a two‐step carbanion mechanism (Scheme 2) involving the ionization of the aminoalkohol 2a and its esters 2b–2e to the imonium ion 3 and the carbanions 4a–4e. The latter undergo competitive cleavage, recombination and protonation to 5, 2 and 9, respectively, depending on the nucleofugal activity of –X.

These conclusions are supported by the first‐order rate constants for the benzoates 2b–2e which differ merely by a factor of three. Since the p‐substituents in the benzoate groups have only a minor effect on the reaction rate the bonds to the nucleofugal groups are not appreciably broken in the rate determining step.
Untersuchungen über Enzymaktivitäten der Leberzelle bei Vitamin‐E‐Mangel
Authors: Bernhard Karl , Markstein Rudolf
Published: December 2004

The enzymatic elongation of acyl‐CoA esters by malonyl‐CoA, respectively de novo synthesis of fatty acids from malonyl‐CoA by liver microsomes and non particulate fraction of α‐tocopherol deficient rats is diminished versus controls. However, liver microsomes of vitamin E deficient rats synthesize more eicosatetraenic acid from γ‐linolenic acid and more γ‐linolenic acid from linolic acid than do those of tocopherol supplemented animals. It has often been shown that the liver phosphatides of tocopherol deficient rats contain more arachidonic acid than those of controls, a fact which can be explained now by increased activity of the enzymes involved in the biosynthesis of arachidonic acid. Certain polyenic fatty acids are more rapidly synthesized in the absence of naturally occuring antioxidants.

Some enzymes of the respiratory chain have also been examined. No vitamin E deficiency effect has been found on enzymes such as gluconate‐6‐P‐dehydrogenase, isocitrate‐dehydrogenase, malate‐dehydrogenase and lactate dehydrogenase contained in the non particulate fraction. Sonicated mitochondria of tocopherol deficient rats show a greater activity towards cytochrome, oxydase and β‐hydroxy‐acetyl‐CoA‐dehydrogenase than controls, possibly due to ultrastractural alteration of this particle.
Intramolekulare Diels‐Alder‐Additionen in 6‐Methyl‐6‐(penta‐2,4‐dienyl)‐cyclohexa‐2,4‐dien‐1‐on‐Systemen. Vorläufige Mitteilung
Authors: Greuter H. , Fráter Gy. , Schmid H.
Published: December 2004

Thermal rearrangement of trans‐penta‐2,4‐dienyl mesityl ether (trans‐1) gave, besides trans, cis‐2 and trans, trans‐2, the homotwistanone derivative 1,3,10‐trimethyl‐tricyclo[5.4.0.03,9]undeca‐5,10‐dien‐2‐one (3) as well as its isomer 1,3,9‐trimethyl‐tricyclo[5.3.1.03,8]undeca‐5, 9‐dien‐2‐one (4). The tricyclic ketones 3 und 4 were shown to be products of intramolecular Diels‐Alder addition in the intermediate 2,4,6‐trimethyl‐6‐(penta‐2,4‐dienyl)cyclohexa‐2,4‐dien‐1‐one (5). Preparation of 2,6‐methyl‐6‐(3‐methyl‐penta‐2,4‐dienyl)‐cyclohexa2,4‐dien‐1‐one (6) and subsequent heating of 6 in benzene gave the homotwistanone derivative 1,3‐6‐trimethyl‐tricyclo5.4.0.03,9]undeca‐5,10‐dien‐2‐one (7) together with its isomer 1,3,6‐trimethyl‐tricyclo[5.3.1.03,8]undeca‐5,9‐dien‐2‐one (8) in good yield.
Notiz über die Massenspektren cyclischer Ketale
Authors: Böhm R. , Bild N. , Hesse M.
Published: December 2004

The mass spectral behavior of substituted 2‐phenyl‐1, 3‐dioxolanes has been studied. In the spectra of this group of compounds the most important peak is m/e 105 for which benzoylonium structure b is proposed. Another interestingion in the mass spectra of these compounds is c. This ion is protonated benzoic acid.
The Conformation and Chirality of α‐Diketones
Authors: Hug W. , Wagnière G.
Published: December 2004

Our deductions of the chirality of α‐diketones from the skewed glyoxal model [2] have recently been questioned [1]. In particular it has been suggested [1] that the longest‐wave‐length Cotton effect is not determined by the chirality of the chromophore, but rather by contributions from substituents. Arguments against this view are given here and it is concluded that the skewed glyoxal model is still the best starting point for discussion of the optical activity of α‐diketones. To settle the question unambiguously, further spectroscopic data are necessary, however.
The Gas‐Phase Thermal Decomposition of 5‐Ethyl‐1‐pyrroline
Authors: Cocks Alan T. , Egger Kurt W.
Published: December 2004

The gas‐phase thermal decomposition of 5‐ethyl‐1‐pyrroline has been studied in the temperature range 721–786 K. The decomposition appears to proceed by two pathways, one a radical route yielding pyrrole, ethylene and ethane as major products, and the other a molecular hydrogen elimination to form initially 2‐ethyl‐3H‐pyrrole which rapidly rearranges to other ethylpyrroles via a series of 1,5‐hydrogen shifts. Approximate rate constants for the unimolecular hydrogen elimination have been calculated and fit the Arrhenius relationship:

Approximate calculations based on the radical pathway yield a value of ∼14 kcal mol−1 for the stabilization energy in the 1‐pyrrolin‐5‐yl radical, in good agreement with that reported earlier for the substituted 2‐aza‐allyl radical.
Hydroxyalkylierung von Bishydantoinen und Bisdihydrouracilen mittels Epoxiden
Authors: Habermeier J. , Porret D.
Published: December 2004

Aus 1,1′‐Methylen‐bis‐(hydantoinen), 1,1′‐Methylen‐bis‐(dihydrouracilen) und Bis‐(hydantoinyl‐3)‐alkanen erhält man durch Additionsreaktionen mit Oxiranen des Typs Äthenoxid folgende Dialkohole: 1,1′‐Methylen‐bis‐[3‐(2′‐hydroxyalkyl)‐hydantoine], 1,1′‐Methylen‐bis‐[3‐(2′‐hydroxyalkyl)‐5,6‐dihydrouracile] und α,ω‐Bis‐[1‐(2′‐hydroxyalkyl)‐hydantoinyl‐3]alkane. Einige ihrer Eigenschaften und ihre weitere Reaktion mit Oxiranen werden beschrieben.
Zur Reaktionsweise von Enaminen mit Cyclopropenonen I. Einsatz von Cyclododecanon‐Enamin
Authors: Steinfels M. A. , Dreiding A. S.
Published: December 2004

Monomethyl‐, dimethyl‐, di‐n‐propyl‐ and diphenyl‐cyclopropenone (6 to 9) have been reacted with 1‐(N‐pyrrolidino)‐cyclododecene (5) and three types of products isolated.

The major products (40–7% yield) were shown to have the 3‐(cyclododec‐1′‐E‐enyl)Z‐/or E‐acryl‐pyrrolidide structure (12, 13/14, 15/16, 17) by their spectral properties and lithium aluminium hydride reductions as well as, in one case (13), by an alternative synthesis of a stereomer (34) via 1‐(cyclododec‐E‐ene)‐carboxaldehyde (29) and a Wittig reaction. These ‘amides’ are the result of a novel reaction, called ‘C, N‐insertion’.

In the reactions of the symmetrical cyclopropenes 7 to 9 with 5, the minor products (6–10%) proved to have the 2,4‐disubstituted cyclopentadeca‐4‐E‐en‐1,3‐dione structures 38 to 40. These ‘β‐diketones’ are considered to be the hydrolysed forms of the intermediate 1‐(N‐pyrrolidino)‐cyclopentadeca‐1,4‐dien‐3‐ones (45).They are formed by reactions (called ‘C,C‐insertions’), which represent the first cases of direct ring expansions by three carbon atoms.

Such ‘C,C‐insertions’ have been postulated previously by other authors. However, their products do not behave like precursors of our ‘β‐diketones’ but rather like our ‘amides’. It is proposed therefore, that a reinterpretation of these reactions in the literature must be considered in the light of our ‘C, N‐insertion’.

In one reaction (8 + 5) a bicyclo[10. 3. 0]pentadeca‐12‐en‐14‐one dericative 42 was found in 10% yield. This type of product and reaction (called ‘condensation’) has been reported previously.

A suggestion is made for a systematic representation of the several types of reactions, which cyclopropenones can undergo with enamines. – Mixing 9 + 5 in the cold produced an intermediate, which insomerised on heating to the ‘amide’ 17. Its properties are compared with those of recently described similar ‘primary adducts’ and the latter are reexamined in the light of the new product interpretations reported in this paper. A novel structure is considered for this intermediate, that a of cycle ‘ammonium acylid’ 51. An attempt is made at the formulation of other possible intermediates.