bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass Spectrometric Decomposition Processes in Labelled 1‐Heptenes
Authors: Falick Arnold M. , Gäumann Tino 
Published: December 2004

AbstractThe 70 eV mass spectra of a number of 13C‐ and D‐labelled analogs of 1‐heptene have been measured, as well as the metastable transitions in the non‐labelled compound. Isotopic distributions in the major fragment ions have been calculated from the high and low resolution data. The results show that considerable skeletal rearrangement must take place before formation of most of the fragment ions. Loss of methyl and ethyl radicals occurs mainly from the two ends of the molecule. Ethylene fragments come primarily from the unsaturated end of the molecule, but show evidence of significant prior skeletal rearrangement. The predicted McLafferty rearrangement accounts for only 2/3 of the C4H8+ ions formed, less for the C3H6+ ions. At least 80% of C4H9+ ions appear to be formed by allylic cleavage, as expected, but this mechanism can only account for a maximum of 20% of the formation of the complementary ion C3H5+. Both, this latter ion and C3H6+, are probably generated by loss of hydrogen from C3H7+.Figures obtained for label retention in 1‐[13C]‐ and 1‐D‐labelled analogs were nearly identical for most fragment ions, probably indicating that the hydrogen atoms in position 1 remain on C(1) even following skeletal rearrangement. A similar result was found for the 7‐[13C]‐ and 7‐D‐labelled compounds. The main exceptions in the case of the products labelled in position 1 (C4H7+, C3H3+) seem to be due to initial loss of an hydrogen atom from this position followed by further fragmentation.
Photoinduzierte Cycloadditionen von 2,2‐Dimethyl‐3‐phenyl‐2H‐azirin an Nitrile und «push‐pull»‐Olefine. 43. Mitteilung über Photoreaktionen
Authors: Stegmann Werner , Gilgen Paul , Heimgartner Heinz , Schmid Hans 
Published: December 2004

Photoinduced Cycloadditions of 2,2‐Dimethyl‐3‐phenyl‐2H‐azirine with Nitriles and ‘push‐pull’ Olefines.Electron deficient nitriles of the type 5a–e in contrast to nonactivated nitriles undergo regiospecific [2+3]cycloadditions to benzonitrile isopropylide (2b), which was generated in situ by irradiation of 2,2‐dimethyl‐3‐phenyl‐2H‐azirine (1b), to yield the 2H‐imidazole derivatives 6a–e (Scheme 2). The structure of the photoproducts was mainly deduced from 13C‐NMR. and mass spectrometry.Whereas normal olefins or enolethers do not react with 2b, push‐pull olefins of the type 10a–d readily undergo the cycloaddition to give the 3‐alkoxy‐5,5‐dimethyl‐2‐phenyl‐1‐pyrrolines 11a–d (Scheme 3 and 4). The structure of the photoproducts 11a–d indicates that the regiospecificity of the cycloaddition corresponds to that of acrylonitriles and acrylesters with 2b.
Enthalpy and Entropy of Formation of Alkali and Alkaline‐Earth Macrobicyclic Cryptate Complexes [1]
Authors: Kauffmann Elisabeth , Lehn Jean‐Marie , Sauvage Jean‐Pierre 
Published: December 2004

AbstractThe enthalpies and entropies of complexation of alkali and alkaline‐earth metal cations by several macrobicyclic ligands have been obtained from calorimetric measurements and from the previously determined stability constants [2]. Both enthalpy and entropy changes play an important role in the stability and selectivity of the complexes. Particularly noteworthy are the large enthalpies and the negative entropies of complexation obtained for the alkali cation complexes (Na+, K+, Rb+ and Cs+ cryptates). The Sr2+ and Ba2+ as well as [Li+ ⊂ 2.1.1]For use of the symbols see [2].
and [Na+ ⊂ 2.2.1] cryptates are of the enthalpy dominant type with also a favourable entropy change. The Ca2+ and [Li+ ⊂ 2.2.1] cryptates are entirely entropy stabilized with about zero heat of reaction. The high stability of the macrobicyclic complexes as compared to the macromonocylcic ones, the cryptate effect, is of enthalpic origin. The enthalpies of complexation display selectivity peaks, as do the stabilities, whereas the entropy changes do not. The high M2+/M+ selectivities found in terms of free energy, may be reversed when enthalpy is considered in view of the very different role played by the entropy term for M2+ and M+ cations. The enthalpies and entropies of ligation show that whereas the cryptate anions are similar in terms of entropy irrespective of which cation is included, the ligands, despite being more rigid than the hydration shell, are nevertheless able to adjust to some extent to the cation. This conclusion agrees with published X‐rays data. The origin of the enthalpies and entropies of complexation is discussed in terms of structural features of the ligands and of solvation effects.
Molecular Orbital Studies of the Protonation of Diazomethane
Authors: Niemeyer Hermann M. 
Published: December 2004

AbstractCNDO/Z, MINDO/3 and ab initio molecular orbital calculations indicate that C‐protonated diazomethane is more stable than N(end)‐protonated diazomethane. Extrapolation of these results to solution chemistry as well as the kinetic references of protonation of diazomethane are discussed.
Kalorimetrische Untersuchungen des Wassereinflusses auf den Lösungsvorgang von Aerosol OT in apolaren Lösungsmitteln
Authors: Christen Heinz , Eicke Hans‐Friedrich , Hammerich Holger , Strahm Ulrich 
Published: December 2004

Calorimetric Investigations of the Effect of Water on the Solution Process of Aerosol OT in Apolar Media.Heats of solution of Aerosol OT in apolar solvents are influenced considerably by already small amounts of water. Calorimetric investigations of the solution process with differently dried surfactant and solvent samples showed the predominating effect on the heats of hydration with regard to the ionic and polar groups of the surfactant. Only if the hydration is finished prior to the process of solution, the latter is endothermic.An estimation of the various enthalpic contributions demonstrates that the destruction of the coherence of the built‐in water within the surfactant is decisive in the latter case. Two models corresponding to definite structures of the liquid crystalline mesophase of the surfactant show very satisfactory agreement with the experimental ΔH‐values.
Addition du chlorure de nitrosyle et de l'oxyde d'azote(III) sur l'allyltriméthylsilane et sur l'allylbenzyldiméthylsilane
Authors: Jolibois Henri , Doucet André , Perrot Roger 
Published: December 2004

Additions of Nitrosyl chloride and Dinitrogen trioxide to Allyltrimethylsilane and Allylbenzyldlmethylsilane.The reaction of nitrosyle chloride and dinitrogen trioxide with allyltrimethylsilane and allylbenzyldimethylsilane leads to nitrosochlorides and to pseudonitrosites. The structures of these compounds are proved by reduction to amines.
Zur Frage der Ladungsverteilung in ionischen π‐Systemen
Authors: Müllen Klaus 
Published: December 2004

On the Charge Distribution in Ionic π‐SystemsThe charge distribution in the anthracene dianion and dication is investigated by means of 13C‐NMR. spectroscopy and compared with the spin density distribution in the corresponding radical ions. It appears that the excess charge in the dianion is distributed in a highly non‐uniform manner and that, quite surprisingly, the quaternary carbon atoms bear positive charges. These findings can be rationalized by means of MO‐models.
The Structure of the Ion Pairs Formed by the Radical Anion of [2.2] Paracyclophane and the Potassium Cation
Authors: Gerson Fabian , Martin William B. , Wydler Christoph 
Published: December 2004

AbstractThe structure of the title ion pairs has been established by ESR. studies of the radical anion produced from 1,1,10,10,12,13,15,16‐octadeuterio[2.2]paracyclophane with potassium in tetrahydrofuran and 2‐methyltetrahydrofuran. The counter‐ion K⊕, which for steric reasons is forced to reside outside the framework of [2.2]paracyclophane, assumes a position above the centre of one benzene ring. Experimental support has been also obtained for the assignment of the coupling constants to those ring and methylene protons which are rendered non‐equivalent by the ion pairing.
Mycelprodukte höherer Pilze. 1. Mitteilung. Phenoxazin‐Derivate in Calocybe gambosa
Authors: Schlunegger Urs Peter , Kuchen Arnold , Clémençon Heinz 
Published: December 2004

Mycelium Products in Higher Fungi. I. Phenoxazine Derivatives in Calocybe gambosa.Phenoxazone and α‐Amino‐phenoxazone have been detected in cultured mycelium of Calocybe gambosa (FR.) DONK.
A 13C‐ and 15N‐NMR. Study of Some 1‐Aryl‐3, 3‐dimethyl Triazene Derivatives
Authors: Axenrod Theodore , Mangiaracina Pietro , Pregosin Paul S. 
Published: December 2004

Abstract13C‐ and 15N‐NMR. spectra have been measured for a series of triazenes. The results are compatible with the significant contribution of a structure such as II. One‐bond nitrogen‐nitrogen coupling constants are reported.
Microbial Transformation of (−)‐Δ1‐3,4‐trans‐Tetrahydrocannabinol by Cunninghamella blakesleeana LENDER
Authors: Binder Michael 
Published: December 2004

AbstractIncubation of (−)‐Δ1‐3, 4‐trans‐tetrahydrocannabinol (= Δ1‐THC; 3) with stationary cultures of Cunninghamella blakesleeana LENDER (Zygomycetales) (ATCC 8688a) yielded a number of metabolic conversion products. Isolation and structure elucidation of 6α‐hydroxy‐Δ1‐THC (4), the potential psychoactive 3″‐hydroxy‐Δ1‐THC (2) and 4″‐hydroxy‐Δ1‐THC (1), and the hitherto unknown metabolites 4″‐hydroxy‐6‐oxo‐Δ1‐THC (5), 4″, 6α‐dihydroxy‐Δ1‐THC (7) and 4″, 7‐dihydroxy‐Δ1‐THC (6) is described.
Etude dans la série des radicaux hétérocycliques: partie XIV. Radicaux diméthyl‐3, 4‐isoxazolyl‐5. Réactivité en série aromatique et hétéroaromatique: nouvelle voie d'accès à des diméthyl‐3, 4‐isoxazoles subsitués en C(5) par des groupements aryle et hétéroaryle
Authors: Vernin Gaston , Siv Chhan , Treppendahl Svend , Metzger Jacques 
Published: December 2004

The aprotic decomposition of 5‐amino‐3, 4‐dimethyl‐isoxazole with excess isoamyl nitrite in aromatic solvents (alkylbenzenes, polyalkylbenzenes, anisole etc.) and in heteroaromatic solvents (thiophene, 2, 4‐dimethylthiazole, pyridine, 4‐alkylpyridines, dimethyl‐ and trimethyl‐pyridines) leads to 5‐aryl‐ and 5‐heteroaryl‐isoxazoles in yields of about 40%. This method provides a new way of obtaining 5‐iodo‐3, 4‐dimethyl‐isoxazole by the aprotic decomposition of the corresponding amine in the presence of iodine (yield: 30%).The relative reactivity of the 3,4‐dimethylisoxazol‐5‐yl radical in alkyl benzenes, in anisole and in alkylpyridines is very similar to that of other heteroaromatic radicals with the radical site next to a sulfur or an oxygen atom. The radical shows electrophilic character because of the inductive effect of the oxygen atom. In the pyridine series an abnormally high percentage of 2‐substitution occurs. This may be explained by a solvatation effect. The characteristic GLC., NMR. and MS. data are reported for most of the compounds studied.
2‐ und 6‐Methyl‐8‐oxa‐bicyclo[5.1.0]octa‐2,4‐dien. Über den Verlauf der Ringöffnung bei der Thermolyse in der Gasphase
Authors: Schiess Peter , Fünfschilling Peter 
Published: December 2004

2‐ and 6‐Methyl‐8‐oxabicyclo[5.1.0]octa‐2,4‐diene. Ring cleavage reaction upon flash pyrolysis.6‐Methyl‐8‐oxa‐bicyclo[5.1.0]‐octa‐2,4‐diene (1 a) has been subjected to flash pyrolysis with the aim to elucidate the course of its thermal ring cleavage reaction. At 100° equilibrium between 1a (6%) and its 2‐methylisomer 1 b (94%) is reached through a remarkably facile [1,5]‐hydrogen shift. Above 200° methyl‐bicyclo[3.2.0]hept‐2‐ene‐7‐ones (3), dihydrotolualdehydes 5 and 6 and their aromatization products 7 are isolated. It is concluded that these products arise from 2‐, 3‐ and 7‐methyl‐hepta‐2,4,6‐trienal 2a, 2b and 2f which are formed from 1a/1b by path C and D in Scheme 2 involving a formal [2+6]‐cycloreversion reaction of 1a/1b and of its valence isomer, 1,2‐homooxepine 11. Two alternate pathways, A and B, involving cleavage of the C,C bond common to both rings in 1 concomitant or followed by hydrogen shifts are not operative.
Umwandlung von 6‐Methyliden‐tricyclo[3.2.1.02,7]oct‐3‐en‐8‐onen in Norcaradien/Cycloheptatrien‐Derivate
Authors: Mukherjee‐Müller Gabriele , Winkler Tammo , Zsindely Janos , Schmid Hans 
Published: December 2004

Transformation of 6‐Methyliden‐tricyclo[3.2.1.02,7]oct‐3‐en‐8‐ones into Norcaradiene/Cycloheptatriene‐Derivatives.Tricyclic ketones of type 1,5‐dimethyl‐6‐methyliden‐tricyclo[3.2.1.02,7]oct‐3‐en‐8‐one (1) [1] rearrange on heating with sodium methylate mainly to methyl‐7‐methyl‐bicyclo[4.1.0]hepta‐2,4‐dien‐7‐carboxylates = methyl‐7‐methyl‐norcaradien‐7‐carboxylates (4). Moreover, the formation of methyl 2‐aryl‐propionate (5) is observed. Thus, tricyclic 1 gives a mixture of norcaradiene derivatives 2 and 4 in 50% yield together with 13% of methyl 2‐(2′, 3′‐dimethylphenyl)‐propionate (5) (Scheme 1). Similarly the tricyclic ketone 7 rearranges to norcaradienes 8 and 9 (31,5%) and methyl 2‐(2′, 3′, 5′‐trimethylphenyl)‐propionate (10, 4%). In this case, the reduction products of 7, i.e. the alcohols 11 (24%) and 12 (8%) as well as other products derived from 11 are observed; heating of the endo‐alcohol 11 with sodium methylate leads to the 2‐arylpropan‐1‐ols 13 and 14 (Scheme 2). Under the same conditions the ketone 18 affords the norcaradiene ester 20 (Scheme 3). Scheme 4 shows the rearrangement of the pentacyclic ketone 21 to the cycloheptatriene derivative 22 and the base catalysed isomerisation of 22 to 23.The structure elucidations were achieved with the help of UV.‐, IR.‐ and mainly NMR. spectra. The carboxy or methoxycarbonyl group assumes the exo‐position in all the norcaradiene derivatives (NMR., also in the presence of NMR. shift reagents). The cycloheptatriene‐noncaradiene‐equilibrium is shifted to the norcaradiene side to > 95% in compounds 2, 4, 8 and 9 and to > 90% in 19 and 20. This is due to the 7‐exo‐carboxy or 7‐exo‐methoxycarbonyl group and the methyl groups in positions 2 and 3 (cf. Klärner [9], chapter 4). On the other hand, in the case of 22 the cycloheptatriene structure is almost exclusively predominant.The most probable mechanism for the rearrangement of tricyclic ketones of type 1 to methylnorcaradien‐7‐exo‐carboxylates or to the corresponding carboxylic acids is depicted in Scheme 5. Thus, the reaction path leads from 1 through a, c, f, g and h to 4. The aromatization reaction of 1 to 5 and 3 proceeds preferentially through a, c (Scheme 5) and k (Scheme 6). The conversation of the tricyclic endo‐alcohol 11 to 2‐aryl‐propan‐1‐ols 13 and 14 using sodium methylate occurs to ca. 90% via m → n and ca. 10% via m → p (Scheme 7); the primarily formed 2‐aryl‐propanals are reduced under the reaction conditions. The exo‐isomer 12 shows no similar reaction.
Facteurs stériques influençant la transposition de Wagner‐Meerwein des carbocations de type pinanyle
Authors: Barthélémy Michel , Gianfermi Anne , Bessière Yvonne 
Published: December 2004

Steric factors influencing Wagner‐Meerwein rearrangement of pinanyl carboniumions.The course of the Wagner‐Meerwein rearrangement of ions obtained by protonation of substituted α‐ or β‐pinenes is strongly dependent on the configuration of the substituents. The situation is complicated by the possibility of double bond isomerisation (α‐→β‐pinenes) before rearrangement. Simple rules for predicting the products are given.
Physico‐chemical properties of deuteriated compounds 3rd communication. The viscosity of n‐heptane
Authors: Öz Hami , Gäumann Tino 
Published: December 2004

AbstractThe kinematic viscosity of mixtures of perdeuteriated and protiated heptane has been measured between 15° and 35° and is given in polynomial form as a function of concentration and temperature. Using the McAllister equation to describe viscosity [4], it can be shown that the interactions between molecules containing the same or different isotopic species differ slightly.
A Chemical Study of Virginia Tobacco Flavour (Nicotiana Tabacum L.). I. Isolation and Synthesis of Two Bicyclodamascenones
Authors: Demole Edouard , Enggist Paul 
Published: December 2004

AbstractAged Virginia tobacco was steam‐distilled and the resulting condensate investigated by chromatographic methods. This allowed identification of the bicyclodamascenones A and B in a small subfraction from this condensate. Both these ketones, which are novel tobacco constituents, were also synthesized and a possible mechanism is proposed for their formation via acid‐catalysed cyclization of β‐damascenone (1).
Die Synthese von 1,3‐disubstituierten Adamantanen
Authors: Fischer Walter , Grob Cyril A. , Katayama Hajime 
Published: December 2004

Synthesis of 1,3‐Disubstituted Adamantanes.A series of new 1‐substituted 3‐bromoadamantanes has been prepared. An improved method for the formation of cyclopropanes from olefins with diazomethane and copper salts is described.
Isolation and Structure of Eucosterol and 16 β‐Hydroxyeucosterol, Two Novel Spirocyclic Nortriterpenes, and of a New 24‐ Nor‐5α‐chola‐8, 16‐diene‐23‐oic Acid from Bulbs of Several Eucomis Species
Authors: Ziegler René , Tamm Christoph 
Published: December 2004

AbstractEucosterol and 16 β‐hydroxy‐eucosterol which have been isolated from several Eucomis species have been shown to be (23S)‐17,23‐epoxy‐3β,31‐dihydroxy‐27‐nor‐5α‐lanost‐8‐ene‐15,24‐dione (1) and (23 S)‐17,23‐epoxy‐3β,16β,31‐trihydroxy‐27‐nor‐5α‐lanost‐8‐ene‐15,24‐dione (2) by chemical transformations and spectral data. The spiro‐fused furanoic ether linkage of both metabolites represents a novel structural element for natural nortriterpenes. The structure of another metabolite (16), 3β‐hydroxy‐4β‐hydroxymethyl‐4,14α‐dimethyl‐15‐oxo‐24‐nor‐5α‐chola‐8,16‐diene‐23‐oic acid, from Eucomis autumnalis (Mill.) Chitt. was elucidated by chemical correlation of its methyl ester 17 with a degradation product of eucosterol (1).
Über Reaktionen oxygenierter Kobalt(II)‐Chelate. VII. Zur Stabilität einfach und doppelt verbrückter μ‐Peroxo‐dikobalt(III)‐Komplexe
Authors: Braun‐Steinle Dorothee , Mäcke Helmut , Fallab Silvio 
Published: December 2004

On reactions of oxygenated Cobalt(II) Chelates. VII. Stability of mono and doubly bridged μ‐Peroxo‐dicobalt(III) Complexes.The oxygen carrier properties of the cobalt(II) chelates of symmetrical diethylenetriamine‐4‐acetic acid (dtma) and unsymmetrical ethylenediamine‐1,1‐diacetic acid (edda) have been investigated by O2 equilibrium measurements in alkaline solution. Maximum O2 uptake is at pH = pKH (4), indicating that μ‐peroxo‐μ‐hydroxodicobalt(III) ion is the only oxygenated species formed in aqueous solution. Relationships between stability and structural factors are discussed.
1‐Aralkylated Tetrahydro‐2‐benzazepines. Part III. Synthesis from β‐tetralones
Authors: Berney Daniel , Schuh Karlheinz 
Published: December 2004

Abstract1‐Benzyl‐tetrahydro‐2‐benzazepin‐3‐ones 4 were prepared by submitting the corresponding 1‐benzyl‐β‐tetralones 3 to the Schmidt reaction. On the other hand, the rearrangement of the tetralones 3 by the Beckmann procedure gave 1‐benzyl‐tetrahydro‐3‐benzazepin‐2‐ones 5. The syntheses of some hexahydrophenanthro‐azepines of types 10 and 15 are also described.
Nucleophilic and Electrophilic Properties of Carbenes, II. 4‐Biphenylyl‐4‐pyridylcarbene
Authors: Lán Nguyňñ Mǒng , Wentrup Curt 
Published: December 2004

AbstractFlash pyrolysis of 4‐biphenylyl‐4‐pyridyldiazomethane (4 gave 7‐phenyl‐2‐azafluorene)5, which was also synthesized from 3‐mesitoylpyridine in four steps. 4‐Biphenylyl‐4‐pyridyl‐[13C]‐diazomethane (9) was prepared from isonicotinic [13C]‐acid chloride in three steps. Flash pyrolysis of 9 established that 4a‐ and 4b‐[13C]‐7‐phenyl‐2‐azafluorenes are formed in a carbene‐carbene rearrangement in which ring expansion of the biphenyl part dominates over that of the pyridine ring. These results support the postulate that carbene‐carbene rearrangements are favoured by a nucleophilic interaction between the filled singlet carbene sp2 (σ) orbital and the lowest unoccupied molecular orbital (LUMO) of the aromatic ring.
Synthese eines 17β‐homologen 3β‐Hydroxy‐card‐5,22‐dienolids Partialsynthetische Versuche in der Reihe der Herzgifte, 8. Mitteilung
Authors: Güntert Theodor W. , Linde Horst H. A. , Ragab Mohamed S. , Spengel Sigrid 
Published: December 2004

Synthesis of a homologous 3β‐hydroxycard‐5,22‐dienolide.We describe the synthesis of 4′‐[(3β‐hydroxy‐androst‐5‐en‐17β‐yl)methyl]‐2′(5′)‐furanone (22) starting from 3β‐acetoxy‐androst‐5‐ene‐17β‐carboxylic acid (5).
A 300 MHz NMR. Evidence for the Configuration of Roxburghine B
Authors: Cistaro Carla , Mondelli Rosanna , Anteunis Marc 
Published: December 2004

AbstractThe 300 MHz1H‐NMR. spectrum of the alkaloid Roxburghine B is completely analysed. The coupling constant values give evidence for the configuration, which is revised toepi‐allo: H(3β), H(15α), H(20α) and C(18β).
Synthesis of 7‐Deamidocephalosporin Lactone. Preliminary Communication
Authors: Schmid Gérard , Prasad Kapa K. , Petrzilka Theodor 
Published: December 2004

AbstractCondensation of azetidinone 1 with mercaptan 3 gave compound 5. Bromination of 5 afforded two isomeric bromohydrins 11a and 11b which differ in the configuration at C(4). Acetylation and reduction with zinc and acetic acid of the above bromohydrins gave 7‐deamidocephalosporin lactone (14).
Dewar Benzene and Some of its Derivatives. A photoelectron spectroscopic analysis [1]
Authors: Bieri Gerhard , Heilbronner Edgar , Kobayashi Tsunetoshi , Schmelzer Andreas , Goldstein Melvin J. , Leight Ronald S. , Lipton Mark S. 
Published: December 2004

AbstractThe near degeneracy of the two lowest ionization energies of Dewar benzene can be understood in terms of closely competitive ‘through‐bond’ and ‘through‐space’ interaction. Empirical, semiempirical, and open‐shell ab initio procedures converge to require mutually consistent symmetry assignments.
Transition‐Metal Complexes with Bidentate Ligands Spanning trans‐Positions. I. The synthesis of 2,11‐bis(diphenylphosphinomethyl)benzo[c]‐phenanthrene, a ligand promoting the formation of square planar complexes
Authors: DeStefano N. J. , Johnson D. K. , Lane R. M. , Venanzi L. M. 
Published: December 2004

AbstractThe bidentate ligand 2,11‐bis(diphenylphosphinomethyl)benzo[c]phenanthrene (1) was synthesized from 2,11‐dimethyl‐benzo[c]phenanthrene (3) via the corresponding bromomethyl derivative 9. 3 was obtained from the cyclization with boron trifluoride etherate of 1,1‐di‐(p‐methylphenethyl)‐epoxyethane (7), which was prepared from 1,5‐di(p‐tolyl)‐pentan‐3‐one (6).
Photocyclisierung von 1‐[3‐(Chloracetylamino)propyl]‐3‐methylindol. 12. Mitteilung über synthetische Indol‐Verbindungen
Authors: Schindler Othmar , Niklaus Peter , Stauss Urs , Härter Hans Peter 
Published: December 2004

Photochemical cyclization of 1‐[3‐(chloroacetylamino)propyl]‐3‐methyl‐indole.Photochemical cyclization of 1‐[3‐(chloroacetylamino)propyl]‐3‐methyl‐indole involving loss of HCl leads to the three isomers 2, 3 and 4, the structures of which have been determined by physical and chemical methods.
13C‐NMR. Spectroscopy of Naturally Occuring Substances. XLII. Conformational analysis of quebrachamine‐like indole alkaloids and related substances
Authors: Wenkert Ernest , Hagaman Edward W. , Kunesch Nicole , Wang Nai‐yi , Zsadon Béla 
Published: December 2004

AbstractThe 13C shifts of 16α‐ and 16β‐substituted derivatives of quebrachamine, 14,15‐dehydroquebrachamine, cleavamine, 15,20α‐dihydrocleavamine and 15,20β‐dihydrocleavamine are determined and correlated with possible conformations of these tetracycles. The method of analysis of the C(16) configuration of these compounds, which emanated from this study, is used for the determination of the configuration of the site of coupling of vindoline and cleavamine β‐chloroindolenine.
Synthesis with 1,2‐Oxazines. II. Synthesis and Properties of 2,3‐dimethyl‐5,6‐dihydro‐4H‐1,2‐oxaziniumiodide
Authors: Hardegger Bruno , Shatzmiller Shimon 
Published: December 2004

AbstractPreparation of 2,3‐Dimethyl‐5,6‐dihydro‐4H‐1,2‐oxaziniumiodide was achieved by N‐alkylation of 3‐methyl‐5,6‐dihydro‐4H‐1,2‐oxazine. Reactions with C‐nucleophiles led to the corresponding N‐methyl‐perhydro‐1,2‐oxazine derivatives. Reaction with sodium hydride in triglyme led to 3‐methyl‐4‐aza‐1,3‐pentadiene.