bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polycarbonyl heterocyclics. [V]. Synthesis of pyrrolo[3,4‐c]pyridine and Furo[3,4‐c]‐pyridine derivatives by the Ring Transformation of Thiazolidine‐4‐on Derivatives
Authors: Zaleska Barbara 
Published: December 2004

Abstract2‐(Aroyl, methylidene)‐3‐aryl‐5‐dicyanomethylene thiazolidine‐4‐on derivatives 2 under morpholine treatment formed complex 3. The acid hydrolysis of 3 leads to pyrrolo [3,4‐c]‐pyridine derivatives 4. On treatment of 3 with aqueous sodium hydroxide and subsequent acidification [3,4‐c]pyridine derivatives 5 are formed.
Aluminiumalkyle mit Heteroatomen. XVI. Untersuchungen zur Struktur von Dialkylaluminium(N‐alkyl/aryl‐N‐silyl)amiden
Authors: Sonnek Georg , Päch Michael 
Published: December 2004

Aluminium Alkyls with Heteroatoms. XVI. Some Investigations on the Structure of Dialkylaluminium (N‐alkyl/aryl‐N‐silyl)amidesDue to their four‐membered Al‐‐N ring structure dimeric dialkylaluminium (N‐organyl‐N‐methylsilylamides) are able to form two stereoisomers. The cis/trans‐equilibrium is determined by the bulk of the substituents R2 and R3 connected with the nitrogen atom and the aluminium atom, respectively. If both substituents are rather small exclusively the trans‐isomer could be detected which has a planar ring. Holding R2 small but letting R3 grow up in volume the cis‐species become more and more favoured. This seems to be based on the fact that the four‐membered ring now exists in an angular form.Bulky substituents R2 lower the stability of the dimers to such an extent that (at least partial) dissociation is possible even at room temperature.Strong electron donors (pyridine) cleave the ring structure even of the most stable dimers.All structural and stability phenomena are discussed on the basis of n.m.r.‐investigations, mass spectrometric and cryoscopic results.
Pyryliumverbindungen. 37. Arylbenzene aus 2,4,6‐Triaryl‐pyryliumsalzen und Carbonsäureanhydriden
Authors: Zimmermann Thomas , Fischer Gerhard W. 
Published: December 2004

Pyrylium Compounds. 37. Arylbenzenes from 2,4,6‐Triarylpyrylium Salts and Carboxylic Acid AnhydridesRefluxing 2,4,6‐triarylpyrylium salts 1 with excess carboxylic acid anhydrides (RCH2CO)2O (2a: R = H, 2b: R = Me) in the presence of condensing agents like sodium or potassium acetate, sodium carbonate or methoxide, triethylamine or pyridine results in 1,3,5‐triarylbenzenes 3 (R = H, Me). Under similar conditions, phenylacetic acid anhydride (2c), generated in situ from sodium phenylacetate and excess 2a or 2b, yields 1,2,3,5‐tetraarylbenzenes 3 (R = Ph). Thus, the reaction 1 + 2 → 3 represents a new and simple method for replacing the pyrylium heteroatom =O⊕– by the =CR– moiety (R = H, Me, Ph). The structure of the arylbenzenes 3 was proved by spectroscopic methods, by comparison with literature data or by independent synthesis. As by‐products 2‐acyloxy‐benzophenones 10 are formed. Reaction of 3,5‐dimethyl‐2,4,6‐triphenyl‐pyrylium perchlorate (11) with acetic acid anhydride/sodium acetate (or sodium phenylacetate) takes another course leading to 2‐acetoxy‐3,5‐dimethyl‐4,6‐diphenyl‐benzophenone (15), whereas treatment of 11 with propionic acid anhydride/sodium acetate follows the reaction scheme 1 + 2 → 3 giving 1,3,5‐trimethyl‐2,4,6‐triphenylbenzene (16). The mechanisms of the different pyrylium ring transformations are discussed.
Trennung der Enantiomeren von (S,R)‐1,1′‐Bi‐2,2′‐naphthyl‐hydrogenphosphat mittels (1R, 2R)‐ bzw. (1S,2S)‐2‐Amino‐1‐(4‐nitrophenyl)‐propan‐1,3‐diol
Authors: Werner W. , Tresselt D. , Ihn W. , Ziebell G. 
Published: December 2004

Resolution of the Enantiomers of (S,R)‐1,1′‐Bi‐2,2′‐naphthylhydrogenphosphate by (1R,2R)‐ and (1S,2S)‐2‐Amino‐1‐(4‐nitrophenyl)‐propane‐1,3‐diolThe resolution of the diastereoisomeric salts of the title compounds was possible in the presence of a ketone, especially acetone, which forms oxazolidines (3a–d) with the chiral bases. These oxazolidines afforded separable salts with the (S,R)‐1,1′‐Bi‐2,2′‐naphthylhydrogenphosphate (4). The structures of these salts were proved by m.s. and n.m.r. spectroscopy.
Synthese substituierter N‐Hydroxylactame, Lactame, Chinolin‐N‐oxide und Chinoline durch katalysierte Reduktive Cyclisierung von 2‐Nitrocinnamoyl‐Verbindungen mit Wasserstoff/Platinschwarz
Authors: Sicker D. , Rabe A. , Zakrzewski A. , Mann G. 
Published: December 2004

Synthesis of Substituted N‐Hydroxylactams, Lactams, Quinoline‐N‐oxides, and Quinolines by Catalyzed Reductive Cyclization of 2‐Nitrocinnamoyl Derivatives with Hydrogen/Platinum BlackSubstituted nitrobenzenes 1a–1m, consisting of two series of 6 analogous compounds, containing the structural unit of an α,β‐substituted 2‐nitrocinnamoyl group have been reductively cyclized by means of hydrogen in the presence of platinum black catalyst to form four types of heterocycles: N‐hydroxylactams 2a and b, lactams 3 and 4, quinoline‐N‐oxides 5a–d, and quinolines 6a and b. The type of substituents at the 2‐nitrocinnamoyl group is of significance for the type of heterocycle formed in this reaction. It is of special interest that by the use of the reduction system hydrogen/platinum black the probability to obtain N‐hydroxylactams or quinoline‐N‐oxides, which are difficult to obtain by alternative procedures, becomes much higher than by the use of many reducing agents acting noncatalytically.
Revisitation of Formaldehyde Aniline Condensation. VII. 1,3,5‐Triarylhexahydro‐sym‐triazines and 1,3,5,7‐Tetraaryl‐1,3,5,7‐tetrazocines from Aromatic Amines and Paraformaldehyde
Authors: Giumanini Angelo G. , Verardo Giancarlo , Zangrando Ennio , Lassiani Lucia 
Published: December 2004

AbstractA product study of the reaction between a number of aromatic amines substituted with widely different groups and paraformaldehyde in inert solvents was performed and found to yield 1,3,5‐triaryl‐1,3,5‐hexahydrotriazines, 1,3,5,7‐tetraaryl‐1,3,5,7‐tetrazocines and formaminals. It was not possible to correlate the product outcomes with the actual structure of the amine substrate. The X‐ray diffraction structural determination of 1,3,5‐tri‐(t‐butylphenyl)‐(1b) and 1,3,5‐tri‐(m‐fluorophenyl)‐1,3,5‐hexahydrotriazine (1c) showed the diaxial arrangement of the N‐substituents.
Synthese neuer substituierter Pyrazolo‐[3,4‐e]‐1,2,4‐triazine
Authors: Heinisch L. 
Published: December 2004

Synthesis of Substituted Pyrazolo‐[3,4‐e]‐as‐triazinesSome new substituted pyrazolo‐[3,4‐e]‐as‐triazines (6a—f, 7a‐c) were synthesized by cyclisation of pyrazoline‐4,5‐dion‐4‐isothiosemicarbazones (5a—c) and ‐4‐amidinohydrazones (4a—f) in phenol at 180—200°C. 3‐Ethylmercapto‐7‐phenyl‐pyrazolo‐[3,4‐e]‐as‐triazine (7a) hydrolyses to the 3‐hydroxyderivative (8) and methylated to the 5‐methylderivative (7b).
Utilization of Macroporous Polymer Containing Phenylboronic Acid Groups in the solid‐ phase synthesis
Authors: Sarhan A. , Ali M. M. , Abd El‐Al M. Y. 
Published: December 2004

AbstractEthylene glycol (4‐vinylphenyl‐)‐boronate (2) was copolymerized with technical divinylbenzene to highly crosslinked macroporous polymer (P2). On treatment of P2 with methanol/water, 75% of the polymer‐bound ethylene glycol could be split‐off, under formation of the desired polymer (P1) with free phenylboronic acid groups. The utility of P1 in the solid‐phase synthesis, for instance its conversion to polymer‐supported phenol, and as polymer‐supported protecting group for diols was investigated.
Crystal and Molecular Structure of Ambrosin and Damsin, sesquiterpene lactone isolates of Ambrosia maritima L
Authors: Iskander George M. , Modawi Barakat M. , Ahmed Hassan E. , Schlemper Elmer O. , Duddeck Helmut 
Published: December 2004

AbstractAmbrosia maritima L. growing wild in central Sudan contained substantial amounts of two principal sesquiterpene lactones, ambrosin and damsin. 1H, 13C‐n.m.r.'s and X ray crystal analyses of these are discussed.Much interest and published results on the sesquiterpene plant isolates [1—9], the pseudoguiano‐lides, ensued from their pharmacological (eg. mollusicidal) activity of the compositae family and in particular the Ambrosinae. From the genus Ambrosia (Compositae, Heliantheae, subtribe Ambro‐sinae) several pseudoguianolides (eg. ambrosonolides) were isolated [7—12]. Recently, two pseudo‐guianolides, damsin and ambrosin were isolated from A. Maritima L. sp. and other six more of these lactones were reported to occur in this species [4].The structures of these compounds were exclusively established through 1H‐ and 13C‐n.m.r. studies which in certain cases were by no means conclusive [4].
Insect growth regulators. XXI. Synthesis of Juvenoids with the 5,5‐dimethylcyclohex‐3‐en‐1‐yl system
Authors: Wawrzeńczyk C. , Lochyński S. 
Published: December 2004

AbstractA new group of juvenoids with the 5,5‐dimethylcyclohex‐3‐ene system was obtained by a multi‐step synthesis starting from (+)‐3‐carene (1). Esters 15, 16 and 18 were synthesized by the Wadsworth‐Emmons reaction of ketone 14 or aldehyde 17 with appropriate phosphonates. Esters 19 and 20 were obtained by the Claisen rearrangement of allylic alcohol 21 with trimethyl or triethyl orthoacetate. Juvenoids obtained were active against Dysdercus cingulatus and were inactive against Tenebrio molitor.
Struktur‐Eigenschaftsbeziehungen an Kernhalogenierten p‐Dimethylamino‐benzendiazoniumsalzen (p‐DABS): IR‐ und UV‐Vis‐spektroskopisches Verhalten und Photolyseeigenschaften
Authors: Fanghänel R. E. , Kriwanek R. J. 
Published: December 2004

Relation between Structure and Properties of Ring Halogenated p‐Dimethylamino‐benzene Diazonium Salts, I.R. and U.V.‐Vis. Spectroscopical Behaviour and PhotolysisThe relation between the molecular structure of the halogene substituted p‐dimethylaminobenzene diazonium salts p‐DABS‐ 1, 1a–k and their i.r.‐ u.v.‐vis.‐spectroscopic and photochemical properties has been investigated. The N–N stretching frequencies and intensities of 1, 1a–k are linearly correlated with special Hammett ΣσR‐constants of the substituents. The u.v.‐vis. spectra of the sterically hindered compounds show a red shift of the absorption maxima together with a strong decrease of the absorption intensity. The angle of twisting between the dimethylamino group and the ring plane has been estimated.From the spectroscopic data the mesomeric, inductive and steric effects of the substituents in the ring of the p‐DABS can be estimated in a quantitative way. The quantum yields of the photolysis of the p‐DABS (λE = 405 nm) were determined in 0,1 n H2SO4 and dioxane/0,1 n H2SO4 (1:1, v/v) in the presence and absence of oxygene. In the sensitized photolysis of selenopyronine (λE = 578 nm) a linear correlation of the quantum yields (lg Φ) and special Σσcorr‐constants are observed. The sensitized photolysis of the polyhalogenated p‐DABS 1f–k take place by a radical chain mechanism.
Ringöffnung von 2‐Oxocyclohexancarboxamid zu 2‐Hydroximinopimelinsäure‐1‐amid
Authors: Bischoff Christian , Schröder Edith 
Published: December 2004

Ring Opening of 2‐Oxocyclohexane Carboxamide to 2‐Hydroximinopimelic‐1‐amideReaction of 2‐oxocyclohexane carboxamide (1) and sodium nitrite in 1n hydrochloric acid yields 2‐hydroximinopimelic‐1‐amide (2).2and dimethylsulphate react to give compounds3and4, respectively,2and 1.6‐diamino hexane form salt5, 2and cyclohexanone (resp. cyclopentanone) yield imidazoline‐N‐oxide6(and7, resp.)2and hydrazine afford pimelic hydrazide (8).
Kinetics and mechanism of isocyanate reactions. I. Reactions of Aryl Isocyanates with Alcohols
Authors: Bacaloglu Radu , Cotarc Livius , Marcu Nicolae , Toulgyi Stefan 
Published: December 2004

AbstractThe reaction of aryl isocyanates with alcohols has been kinetically studied as a model reaction for polyurethane formation under conditions similar to those of industrial scale production.Considering the isocyanate and alcohol structure, kinetic isotopic effect, activation enthalpy and entropy and solvent effects it has been found that the most probable mechanism is the alcohol addition through a four‐membered cyclic transition state.
Partialsynthesen von Cardenoliden und Cardenolid‐Analogen. XIII. Synthese substituierter 14,21‐Epoxy‐5β,14β‐card‐20(22)‐enolide
Authors: Courault Klaus , Lindig Claus 
Published: December 2004

Partial Syntheses of Cardenolides and Cardenolide Analogues. XIII. Synthesis of Substituted 14,21‐Epoxy‐5β,14β‐card‐20(22)‐enolideThe 12‐substituted 14,21‐epoxy‐5β,14β‐card‐20(22)‐enolides 3 and 5 were synthesized by oxidation of the appropriate 17β‐(3‐furyl) derivatives 2b and 2c, respectively, with chromic acid. 5 was converted to the conjugated Δ9(11)‐12‐ketone 6 by dehydrogenation with selenium dioxide.The biological activities of the new compounds were investigated and are discussed.
Radikalreaktionen an N‐Heterocyclen. VIII. ESR‐Untersuchungen zur N‐N‐Bindungsspaltung cyclischer 2,2‐Diacylhydrazinoxyle
Authors: Omelka Ladislav , Kluge Ralph , Reinhardt Michael , Schulz Manfred 
Published: December 2004

Free Radical Reactions of N‐Heterocyclic Compounds. VIII. ESR‐Investigations on the N,N‐Bond Cleavage Reaction of Cylic 2,2‐Diacyclhydrazinoxyls2,2‐Diacylhydrazinoxyls (2) undergo decomposisition to new nitroxides 3 in the presence of bis (acetylacetonato) cobalt (II), tert.‐butyl hydroperoxide and an alcohol (i.e. methanol, ethanol, i.‐propanol). These new radials 3 are spin trap products of nitrosoarenes, formed by a fragmentation process of 2 and of ligand radicals, generated from bis (acetylacetonato) cobalt (II) by oxidation with tert.‐butyl hydroperoxide. The e. s. r. data of the radicals 2, 3 and of the 3‐isomeric radicals 5 and 6 are compared.
Reactions with monothiomalonamides: Synthesis of Polysubstituted Thiazoles
Authors: El‐Reedy A. M. , Hussain S. M. , Youssef M. M. M. 
Published: December 2004

AbstractMonothiomalonamides (1a, b) coupled with arenediazonium salts yield the α‐arylhydrazone derivatives (2a—c), Reaction of 1a, b with α‐haloketones afforded polysubstituted thiazoles 6a—c. Compounds 6 condensed with p‐nitrosodimethylaniline and coupled with arenediazonium salts yield the azomethine derivatives 7a—d and the arylhydrazones 8a—h, respectively.Compounds 1a, b behave differently towards hydrazonyl chlorides, they yielded arylazodimethylthiazoles 13a—c and thiazolylacetanilides 12a—c respectively.
Heterocyclic synthesis with nitriles: A new approach to Thiophene and Thieno‐[2,3‐d]‐pyrimidine derivatives
Authors: Abdelrazek Fathy M. , Ead Hamed A. 
Published: December 2004

Abstractα‐Cyano‐β‐thiocyanatomethyl cinnamonitrile (1) was transformed into 5‐acetyl‐2‐amino‐4‐phenylthiophen‐3‐carbonitrile (3) on refluxing in acetic/sulphuric acid mixture. Compound 3 reacted with trichloroacetonitrile, formamide, carbon disulphide and ethylorthoformate.
Studies on the oxidative cleavage of the CC triple bond during the autoxidation of acetylenic hydrocarbons. IV. The reaction of Acyloxy and Alkoxy Radicals with α‐diketones
Authors: Rao Tarigopula Siva Sankara , Pritzkow Wilhelm 
Published: December 2004

AbstractDibenzoyl peroxide, diacetyl peroxide and di‐tert‐butyl peroxide were thermally decomposed at 130°C in the presence of benzil, 1‐phenyl‐propane‐1,2‐dione, and 1‐phenyl‐butane‐1,2‐dione using chlorobenzene as the solvent. In all cases benzoic acid was formed. Moreover, from 1‐phenyl‐propane‐1,2‐dione and 1‐phenylbutane‐1,2 dione considerable amounts of benzil were obtained. The results show that reactions of the type

equation image

(with X· R′O· or X· R′COO·), previously formulated by us to explain the course of the autoxidation of α‐diketones, really take place.
Steric Effects in the UV‐Vis Spectra of Benzylideneanilines. IV. 1‐(4′‐dimethylaminobenzylideneamino)pyridinium perchlorates and their benzo derivatives
Authors: Gawinecki R. 
Published: December 2004

AbstractAlkyl substituent(s) in the α position(s) of the pyridine ring in 1‐(4′dimethylaminobenzylideneamino)pyridinium perchlorates cause a blue shift of the longest‐wavelength u.v./vis absorption band (LWB). The intensity of the band in the spectra of 2,6‐dialkyl derivatives is lower by ca. 0.5 unit (log ϵ) than that for unsubstituted and monosubstituted compounds. It is assumed that the pyridine ring in the studied compounds is twisted out of the CH  N plane. The syntheses of all compounds studied are described in the paper.
Vicarious nucleophilic Substitution of Hydrogen in Pteridine derivatives
Authors: Mąkosza M. , Ostrowski S. 
Published: December 2004

AbstractPteridine derivatives react in basic media with carbanions bearing leaving groups at the carbanionic center via the vicarious nucleophilic substitution of hydrogen (VNS) pathway. In the reaction with trihalomethyl carbanions covalent σ‐adducts and/or dihalomethylated VNS products can be obtained depending on conditions.
Heterocyclic syntheses with malonyl chloride. 15. 7‐Chloro‐3,4‐dihydro‐4,5‐dioxo‐3‐aryl(or‐alkyl)‐2‐thio‐2H,5H‐pyrano[3,4‐2‐e]‐1,3‐oxazine from aryl or alkyl isothio‐cyanates and their degradation with morpholine and ethanol
Authors: Al‐Rawi Jasim M. A. , Mahmood Abdul‐Hakim Th. 
Published: December 2004

AbstractSubstituted aromatic isothiocyanates with malonyl chloride yield 7‐chloro‐3‐substituted‐3,4‐dihydro‐4,5‐dioxo‐2‐thio‐2H,5H‐pyrano [3,4‐e]‐1,3‐oxazine (1).Alkyl isothiocyanates with malonyl chloride yield a mixture of 7‐chloro‐3‐alkyl‐2‐thio pyranooxazine (2) and the 2‐oxo‐analogue (3).The pyrano oxazine 1 react stepwise with morpholine undergoing replacement of the 7‐chloro substituent yielding the 7‐morpholino analogue (4), then the pyrone ring was opened producing 5‐morpholino carbonyl‐4‐oxo‐3‐substituted phenyl‐2‐thio‐1,3‐oxazine‐6‐ylacetomorpholid (5). Finally the oxazine ring was opened yielding 2‐substituted phenyl carbomyl‐3‐morpholino‐N,N‐glutaconoyldimorpholine (6).Ethanol react with compound 1 at any molar ration causing the opening of the pyrone ring and retain the oxazine ring.Mass spectra. 1H‐n.m.r., u.v. and i.r. spectroscopic data provided information about the fine structures of the products.
Enzymes in organic synthesis. 2. Synthesis of enantiomerically pure prostaglandin intermediates by Enzymatic Hydrolysis of (1SR, 5RS, 6RS, 7RS)‐7‐acetoxy‐6‐acetoxymethyl‐2‐oxabicyclo[3.3.0]octan‐3‐one
Authors: Theil Fritz , Schick Hans , Nedkov Peter , Böhme Monika , Häfner Barbara , Schwarz Sigfrid 
Published: December 2004

AbstractSubtilisin DY as well as alkaline protease from Bacillus licheniformis 41 p catalyze the hydrolysis of (1SR, 5RS, 6RS, 7RS)‐7‐acetoxy‐6‐acetoxymethyl‐2‐oxabicyclo[3.3.0]octan‐3‐one (rac‐1) with practically useful enantio‐ and regioselectivity. Under the hitherto found optimal conditions (1S, 5R, 6R, 7R)‐7‐hydroxy‐6‐hydroxymethyl‐2‐oxabicyclo[3.3.0]octan‐3‐one (4), an important intermediate in prostaglandin syntheses, could be prepared in a yield of 16% with an enantiomeric excess of 99%. The enantiomer (ent‐4) was obtained with the same enantiomeric excess in 20% yield. The chemical yields are related to the racemic starting material rac‐1.
Synthese und Strukturermittlung von Sulfamoyl‐guanidinen
Authors: Schröder H. , Fischer E. , Michalik M. , Oehme G. 
Published: December 2004

Synthesis and Structure Elucidation of Sulfamoyl GuanidinesA series of sulfamoyl guanidines 2a‐‐hyphen;p and 4 was synthesized by addition of sulfurylchloride to dialkylcyanoamides and subsequent aminolysis of the N,N‐dialkyl‐N′‐chlorosulfonyl‐chloroformamidines with primary or secondary amines. Advantageously, the aminolysis can be performed with trimethylsilylamines as amine component by continuous withdrawing of the formed trimethylchlorosilane.Phase transfer catalyzed methylation led to a specific alkylation of the sulfamoyl group to form the 2‐(aryl‐methyl‐sulfamoyl)‐guanidines (5a‐‐hyphen;5g, 5h). All compounds were characterized by m.s.‐, i.r.‐, 1H‐n.m.r.‐ and 13C‐n.m.r.‐spectra. I.r. and 1H‐n.m.r. data show the existence of an intramolecular hydrogen bonding between the guanidine NH group and the SO2 group.
Tetrazolverbindungen. 1. 1‐Aryl‐5‐(2‐dialkylamino‐vinyl)‐1H‐tetrazole aus 3‐Chlor‐propen‐iminiumsalzen
Authors: Fischer G. W. , Herrmann M. 
Published: December 2004

Tetrazole Compounds. 1. 1‐Aryl‐5‐(2‐dialkylamino‐vinyl)‐1H‐tetrazoles from 3‐Chloropropeniminium Salts3‐Chloropropeniminium salts 1 react with excess sodium azide in refluxing alcohols to give mainly 1‐aryl‐5‐(2‐dialkylamino‐vinyl)‐1H‐tetrazoles 3; in minor quantities isomeric 5‐aryl‐1‐(2‐dialkylamino‐vinyl)‐1H‐tetrazoles 4 are formed. The reaction involves splitting off N2 and C → N migration of the aryl and dialkylaminovinyl group, respectively. A cross‐over experiment indicated that the rearrangement step proceeds intramolecularly. — The i.r., u.v., and n.m.r. spectroscopic data of the novel 1H‐tetrazoles 3 as well as the u.v. spectra of some new starting products 1k—v are reported.
Phase transfer catalysed alkylation of enamines of β‐keto carbothionic acid anilides with dihalogenoalkanes: Synthesis of Cyclic S,N‐Acetals of α‐Oxo Ketene
Authors: Bogdanowicz‐Szwed Krystyna , Kozicka Michalina , Lipowska Malgorzata 
Published: December 2004

AbstractAlkylation of 2‐morpholino‐cycloalken‐1‐carbothionic acid anilides 1 and 2 with 1,3‐dibromopropane in a two‐phase system leads to 1‐morpholino‐cycloalken‐3‐aryl‐tetrahydro‐1,3‐thiazine‐2‐ylidene 3 and 4. Reactions of 2‐morpholino‐cyclopenten‐1‐carbothionic acid anilides 5 and 3‐morpholinothiocinnamic acid anilides 8 with 1,2‐dibromoethane yield 1‐morpholino‐cyclopenten‐3‐aryl‐thiazolidine‐2‐ylidene 7 and 2‐(2′‐phenyl‐2′‐oxo‐ethylidene‐3‐aryl)thiazolidine 9, respectively. Alkylation of 1‐indanone‐ and 1‐tetralone‐2‐carbothionic acid anilides 11 and 12 with dihalogenoalkanes yield 1‐oxo‐indanylidene‐ and 1‐oxo‐tetralidenethiazolidines 14, 16 and tetrahydro‐1,3‐thiazines 15, 17, respectively.
Oxidative dimerization of 4‐Alkyl‐6‐phenyl‐2,3‐dihydrooxazines
Authors: Spassov S. L. , Stoeva‐Yordanova K. P. 
Published: December 2004

AbstractReaction mixtures containing 4‐methyl‐(or ethyl‐)‐6‐phenyl‐2,3‐dihydrooxazine kept for some weeks in contact with air at room temperature yielded products of oxidative dimerization (dimorpholinofurans). The structures of the new compounds were determined on the basis of spectral studies and chemical transformations.
Hydropyrene, alicyclische Modellverbindungen für GC–MS‐Untersuchungen
Authors: Mann G. , Sicker A. , Herzschuh R. , Engewald W. , Praefcke K. 
Published: December 2004

Hydropyrenes, Alicyclic Model Compounds for GC–MS InvestigationsHydrogenation of asymmetric and symmetric hexahydropyrene gives the five possible aromatic decahydropyrenes via different octahydropyrenes. From these compounds some dodecahydro‐ and tetradecahydro‐pyrenes, the four isomers of perhydropyrene with chair conformations and five new stereoisomers with twist boat six‐membered rings are obtained. The configurations of the hydrogenated pyrenes are assigned using chromatographic retention indices and mass spectrometric fragmentation in combination with force field calculations.
Studies on the Thermal Conversion of Long‐chain Alkynes at high temperatures in the gas phase
Authors: Ondruschka B. , Zimmermann G. , Ziegler U. , Kopinke F.‐D. , Teuber M. 
Published: December 2004

AbstractIn the gas phase pyrolysis of long‐chain alkynes C5 to C9 at 773 to 873 K, a remarkable portion of molecular reaction (retro‐ene analogous decompositions as well as cycloisomerizations of the parent alkynes to cyclopentenes alkylated in 3‐position) takes place besides the thermal conversion of the starting compounds via radical chain processes. The different products were separated by GC and the main products identified by means of different methods. The mechanisms of formation of the major products are discussed.