bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesekontrolle und Charakterisierung höherer Peptide durch Anwendung der 13C‐NMR‐Spektroskopie
Authors: Schwenzer B. , Scheller D. , Losse G. 
Published: December 2004

Control of Synthesis and Characterization of Higher‐Molecular Peptides by Means of 13C n.m.r. SpectroscopyThe 13C n.m.r. spectra of the C‐terminal bovine insulin decapeptide derivative Boc‐Glu(OBzl)‐Arg(H+)‐Gly‐Phe‐Phe‐Tyr(Bzl)‐Thr(Bzl)‐Pro‐Lys(Z)‐Ala‐OBzl as well as the amino acid and peptide intermediates used in its synthesis, have been measured and assigned as extensively as possible. The use of 13C n.m.r. spectroscopy as a method for controlling the synthesis and for the characterization of higher‐molecular peptides is discussed.
Massenspektroskopie von Naturstoffen. I. Vergleichende Anionen‐Kationen‐Massenspektroskopie von 2,3,4,6‐Tetra‐O‐acetyl‐β‐D‐glucopyranosylestern
Authors: Voigt D. , Lehmann H. 
Published: December 2004

Mass Spectroscopy of Natural Compounds. I.Comparative Investigation of Anion‐Cation Mass Spectra of 2,3,4,6‐Tetra‐O‐acetyl‐β‐D‐glucopyranosyl EstersThe electron attachment mass spectra (anion mass spectra) of 2,3,4,6‐tetra‐O‐acetyl‐β‐D‐glucopyranosyl esters with different structures of the acids are discussed and compared with the corresponding electron impact spectra. In contrast to the cation mass spectra the molecular ion peak appears in all the anion mass spectra.
Folgeprodukte halogenierter Aldehyde. XVI [1]. Untersuchungen über Chloralammoniak
Authors: Schnell M. , Erfurt G. , Zinner H. 
Published: December 2004

Derivatives of Halogenated Aldehydes. XVI. Investigations of ChloralammoniaN‐(1,2,2,2‐Tetrachloroethyl)trichloroacetaldimine 8 is formed by heating of chloral‐ammonia 2 with thionyl chloride. The reaction of 2 with phosphorus pentachloride in ether leads to a mixture of aldimine 8, 1,2,2,2‐tetrachloroethyl‐phosphorodichloridate 5, N‐(1,2,2,2‐tetrachloroethyl)‐phosphorimidic acid trichloride 6 and N‐(1,2,2,2‐tetrachloroethyl)‐phosphoramidic acid dichloride 7. From compound 7, the phosphoramidic acid ester 9, the substituted phosphoric acid triamide 10 and the N‐dichlorophosphoryl trichloroacetaldimine 11 are obtained on treatment with methanol, isopropyl amine or triethyl amine, respectively. Compound 9 is also formed from 6 by reaction with methanol. The data of i. r. spectra are concordant with the assigned structures of the compounds 6–11.
Synthese von Triorgano‐amido‐arsen‐, ‐antimon‐ und ‐wismut‐halogeniden
Authors: Dahlmann J. , Winsel K. 
Published: December 2004

Synthesis of Triorgano‐amido‐arsenic‐, ‐antimony‐ and ‐bismuthhalidesThe preparation of some triorgano‐amido‐metalhalides by addition of various N‐haloamides to organometallic compounds of the type R3M (M  As, Sb, Bi) in polar aprotic solvents under mild conditions is described. The properties of these derivatives are studied. In solution equilibriums of triorgano‐amido‐antimonyhalides, the corresponding dihalides, and diamido compounds are existing, as we proved by 1H‐n.m.r.
Cyansäureester, 27 [1]. Triazino‐benzimidazole aus 2‐Amino‐benzimidazol‐1‐imidsäureestern und carbonylanalogen Verbindungen
Authors: Martin Dieter , Graubaum Heinz 
Published: December 2004

Cyanic Acid Esters. 27. Triazino‐benzimidazoles from 2‐Amino‐benzimidazole‐1‐imid‐esters and Carbonyl Analogic CompoundsThe Cyclocondensation of 2‐amino‐benzimidazole‐1‐imid‐esters with aldehydes, carbonic acid anhydrides and isocyanates has been investigated. With aldehydes in the presence of piperidine 4‐aryloxy‐1,2‐dihydro‐1,3,5‐triazino[1,2‐a]benzimidazoles 3 and with carbonic acid anhydrides 4‐aryloxy‐1,3,5‐triazino[1,2‐a]benzimidazoles 5 are formed. Isocyanates react with the imid esters to the corresponding 3‐substituted ureas 8 which on heating undergo acyl migration of the carbamoyl group followed by cyclocondensation to 4‐imino‐2‐oxo‐1,2,3,4‐tetrahydro‐1,3,5‐triazino[1,2‐a]benzimidazoles 12.
Synthese und biochemische Aktivität perfluoralkylierter Derivate des 5′‐Desoxy‐5′‐fluor und 2′,5′‐Didesoxy‐5′‐fluor‐uridins
Authors: Cech D. , Herrmann G. , Staske R. , Langen P. , Preussel B. 
Published: December 2004

Synthesis and Biochemical Activity of Perfluoroalkylated Derivatives of 5′‐Deoxy‐5′‐fluoro‐, and 2′, 5′‐Dideoxy‐5′‐fluorouridine5‐Perfluoroalkylated 5′‐deoxy‐5′‐fluoro‐, and 2′,5′‐dideoxy‐5′‐fluorouridine are obtained by the reaction of 5′‐fluorouridine or 2′,5′‐dideoxy‐5′‐fluorouridine, respectively, with a perfluoroalkyl‐coppercomplex in DMSO under inert conditions, and at temperatures of about 100 °C. Analogously 5‐perfluoroethyl, 5‐perfluorobutyl, and 5‐perfluorohexyl derivatives of uridine, and 5‐perfluoroethyl, and 5‐perfluorobutyl derivatives of 2′‐deoxyuridine could be isolated. It is shown either by mass spectroscopy or by1H‐n.m.r. spectroscopy that the substitution always takes place at the 5‐position of the pyrimidine. The 5‐perfluoroethyl derivatives are particularly effective as cytostatics.
Molekül‐ und KristallStruktur des Dioxano‐bis(2,4‐dichlorphenoxyacetato)‐kupfer(II) Cu2(2,4‐D)4 · 5 Dioxan
Authors: Reck G. , Jähnig W. 
Published: December 2004

Molecular and Crystal Structure of Dioxano‐bis(2,4‐dichlorophenoxyacetato)‐copper (II) Cu2(2,4‐D)4 · 5 DioxanThe cupric salt of 2,4‐D crystallizes from dioxane solution in the space group P 1 with 2 formula units C16H10O6Cl4Cu and 5 dioxane molecules in the unit cell. The lattice constants are a = 12.557 Å, b = 14.391 Å, c = 9.537 Å, α = 112.56°, β = 99.62° and γ = 92.77°. By X‐ray structure analysis the coordination around the Cu atoms was especially investigated.
Gasadsorptionschromatographie höherer Kohlenwasserstoffe. Normalparaffinbestimmung durch temperaturprogrammierte Segregations‐Gaschromatographie an 5A Molekularsieb
Authors: Eppert G. , Ludwig H. , Schinke I. 
Published: December 2004

Gas Adsorption Chromatography of Higher Hydrocarbons. Determination of Normal Paraffins by Temperature‐Programmed Segregation Gas Chromatography on 5A Molecular SieveA fast temperature program makes it possible to determine the normal paraffins up to C 20 in the concentration range between 0.1 and 99.9 percent (molecule type analysis). From the group peak of the normal paraffins we can obtain on line the distribution of the carbon numbers.As the normal paraffin selectivity of the molecular sieve S ≈ 1 can be assumed. Isoparaffin memory could not be detected.The new method makes it possible to perform analysis with great accuracy within three minutes or less. Connected to a computer it is excellently suitable for large series of samples.Under the standard conditions of this method only a little paraffin cracking has been found. Type and quantity of the cracked products proved to be independent of the chain length of the individual normal paraffin.
Zur Reaktion von Bis‐(dimethylglyoximato)‐nickel(II) mit Hexamethyldisilazen
Authors: Uhle Klaus , Schubert Harald 
Published: December 2004

On the Reaction of Bis‐(dimethylglyoximato)‐nickel(II) with HexamethyldisilazaneThe reaction of bis‐(dimethylglyoximato)‐nickel(II) with hexamethyldisilazane was investigated. Some reactions of the formed nickel(II) dimethylglyoximate are described.
Der kristallin‐flüssige Zustand als Kriterium zur Konstitutionsermittlung von Derivaten tautomeriefähiger heterocyclischer Systeme. I. Kristallin‐flüssige Benzoesäure‐ und Thiobenzoesäure‐pyrimidinyl‐(2)‐ester
Authors: Zaschke H. , Isenberg A. , Schubert H. 
Published: December 2004

The Liquid Crystalline State as a Criterion in Determination of Structure. I. Crystalline Liquid Benzoic Acid and Thiobenzoic Acid Pyrimidinyl‐(2)‐estersThe acylation of subst. 1H‐pyrimidinethiones‐(2) 3 and 4, as well as of subst. 1H‐pyrimidinones‐(2) 7 is investigated. Due to the tautomeric equilibrium in the starting materials the reactions may lead to N‐, S‐, or O‐esters. The liquid crystalline properties of the reaction products formed prove that S‐ and O‐acylated esters 5, 6, and 8 had been formed only. Spectroscopic data confirm this.
Kristallin‐flüssige Thiazole
Authors: Dölling K. , Zaschke H. , Schubert H. 
Published: December 2004

Liquid Crystal ThiazolesThe synthesis of 2,4‐ and 2,5‐disubstituted thiazoles is described and their melting and clearing points are investigated. The influence of the thiazole ring system on the formation of crystalline‐liquid phases is discussed.
Massenspektren alicyclischer Verbindungen. VI. Massenspektrometrisches Fragmentierungsverhalten von Chloressigsäurediestern des trans‐1,4‐Cyclohexandiols
Authors: Borsdorf R. , Remane H. , Arnold M. 
Published: December 2004

Mass Spectra of Alicyclic Compounds. VI. Mass Spectrometric Fragmentation of Chloroacetic Esters of the trans‐1,4‐CyclohexanediolThe electron impact mass spectra of some chloroacetic esters of trans‐1,4‐cyclo‐hexanediol and of cyclohexanol are discussed.It was found that the fragmentation process in these compounds is determined by the number of chlorine atoms in the acid and the interactions between the two functional groups.
Nα‐Acetyl‐aminosäure‐methylamide als Modellverbindungen zur Interpretation der 13C‐NMR‐Spektren geschützter Peptide
Authors: Schwenzer B. , Scheller D. , Losse G. 
Published: December 2004

Nα‐Acetyl‐methylamides of Amino Acids as Model Compounds for Interpretation of 13C‐NMR‐Spectra of Protected PeptidesNα‐Acetyl‐methylamides of differents amino acids have been synthesized as model compounds for amino acid residues in peptides, and 13C‐n.m.r. spectra have been measured.The three derivatives of peptides Boc‐Glu(OBzl)‐Arg(H+)‐Gly‐Phe‐Phe‐Tyr(Bzl)‐Thr(Bzl)‐Pro‐Lys(Z)‐ Ala‐OBzl (B 21–30). Boc‐Leu‐Tyr(Bzl)‐Leu‐Val‐Cys(SEt)‐Gly‐OH (B 15–20) and Boc‐Ser(Bzl)‐His(Trt)‐Leu‐Val‐Glu(OBzl)‐Ala‐OH (B 9–14) used for the synthesis of insulin B chain are an illustration for the fact that chemical shifts of characteristic amino acid carbon atoms obtained by corresponding model compounds, allow a simple and correct interpretation of peptide derivative spectra.
Derivate des Phosphorsäure‐o‐phenylenesters. XIX. Zum Ablauf der Bromierung von Phenyl‐o‐phenylenphosphit
Authors: Gloede Jörg , Gross Hans 
Published: December 2004

Derivatives of o‐Phenylene Phosphates. XIX. Bromination of Phenyl o‐Phenylene PhosphiteThe bromination of phenyl o‐phenylene phosphite does not yield the expected penta‐coordinated phosphorus dibromide 3 but phosphorus tribromide, phenoxy‐bis‐(o‐phenylendioxy)‐phosphorane and tetraphenoxyphosphonium bromide. The mechanism of the reaction is discussed.
Zur Analytik von Kohlenwasserstoffen mit Hilfe der Massenspektrometrie. V. Abhängigkeit der elektronenstoßinduzierten Fragmentierung monocyclischer Kohlenwasserstoffe von der Ringgröße
Authors: Herzschuh R. , Epsch K. 
Published: December 2004

Analysis of Hydrocarbons by Means of the Mass Spectrometry. V. Fragmentation of Monocyclic Hydrocarbons as a Function of the Ring SizeThe E.I.‐spectra of the cycloalkanes CnH2n (n = 5 – 14) and of the cycloalkenes CnH2n‐2 (n = 5 – 12) exhibit strongly influence of the ring strain energies on the stability of molecular ions. Medium‐sized cycloalkanes and cycloalkenes (n = 9 – 11) show exceptional behaviour under the conditions of the electron impact ionization, which is discussed on the base of ring strain effects.
Zur Analytik von Kohlenwasserstoffen mit Hilfe der Massenspektrometrie. VI. Der Einfluß von Ringgröße und Konfiguration auf die Fragmentierung der Bicyclo(n.1.0)alkane und ihrer Halogenderivate beim Elektronenstoß
Authors: Herzschuh R. , Epsch K. 
Published: December 2004

Analysis of Hydrocarbons by Means of the Mass Spectrometry. VI. The Influence of the Ring Size and the Konfiguration on the Fragmentation of Bicyclo(n.1.0)alkanes and their Halogen Derivatives by Electron ImpactThe mass spectra of cis and trans bicyclo(n.1.0)alkanes and their halogen derivatives are discussed. The ring strain energies of these compounds influence the stability of their molecular and fragment ions.
Dipolmomente und Konformation von 3‐ und 4‐Brom‐ und Chlorheteracyclohexanen
Authors: Remane H. , Borsdorf R. , Scholz M. , Dölle E. , Loock P. 
Published: December 2004

Dipole Moments and Conformation of 3‐ and 4‐Bromo and Chloro HeteracyclohexanesThe dipole moments of some 3‐ and 4‐bromo and chloro heteracyclohexanes are measured by the method of Debye and calculated both by the quantum‐mechanical method CNDO/2 and vector addition method.The determination of conformational free energy is made on the basis of measured dipole moments μ of the conformation mixture and the calculated dipole moments μe and μa of the pure conformers. The results are discussed in relation to n.m.r.‐results.
Zur Berechnung der kritischen Mizellbildungskonzentration isomerer und substituierter Alkansulfonate
Authors: Sowada Rudolf 
Published: December 2004

Concerning the Calculation of Values of the Critical Concentration of Mizellization for Isomeric and Substituted Alkane SulphonatesBased on Lin's approach hydrophobicity indices I have been calculated for the isomeric dodecane sulphonates and some substituted alkane sulphonates from published cK data. These I values are useful for estimating cK values of new surface active alkane sulphonates.
Dreikomponentenreaktionen. IX. Methoxychlorierung von Butadien. 1. Produktverteilung bei Chlorunterangebot und Chlorüberangebot
Authors: Beger J. , Schiefer H. , Movsumzade M. M. , Gurbanov P. A. 
Published: December 2004

Three‐Component Reactions. IX. Methoxychlorination of Butadiene. 1. Composition of Reaction Mixtures Obtained Using Either an Excess of Butadiene or an Excess of ChlorineMethoxychlorination of butadiene with 2 mol chlorine gives saturated secondary addition products 5–15, which were found identical with methoxychlorination products of unsaturated primary addition products 1–4 (investigated by capillar GLC). 1, 2 and 3 add chlorine and methanol with high regioselectivity (80–90%); meso and erythro isomer predominate in Markovnikov products from 1 and 2 (87% diastereoselectivity). 5–7 and 11–15 were separated by preparative GLC for structural analysis.
d‐NMR‐Untersuchung der behinderten Rotation am NC(X)‐Bindungsfragment. XII. Substituenteneffekte auf die CN‐Rotationsbarriere in unterschiedlich N‐substituierten Carbamidsäure‐O‐ethylestern
Authors: Kleinpeter E. , Kretschmer M. , Borsdorf R. , Widera R. , Mühlstädt M. 
Published: December 2004

d‐N.M.R.‐Investigation of the Restricted Rotation at the NC(X)‐Bonding Fragment. XII. CN‐Rotational Barrier in Different N‐Substituted Carbamic Acid O‐ethyl EstersThe 1H‐n.m.r. spectra of a series of different N‐substituted urethanes R1R2N‐C(O)OC2H5 are studied at various temperatures. At low temperatures the syn/anti rotamers are assigned by using the LIS‐values of the protons. The thermodynamic parameters ΔGC± of the restricted rotation about the partial C‐N double bond are determined and discussed with regard to inductive, conjugative and homoconjugative effects of the N‐substituents.
Chemistry and application of organic isocyanates. II. Application of tolylene‐2,4‐diisocyanate for the Syntheses of New Surface‐Active Urethanes of poly(oxyethylene)‐sucrose and poly(oxyethylene)glucose
Authors: Lesiak T. , Iwaszkiewicz‐Nowak J. 
Published: December 2004

Chemie und Anwendung von organischen Isocyanaten. II. Verwendung von Toluylen‐2,4‐diisocyanat für die Darstellung von neuen grenzflächenaktiven Poly(oxethylen)saccharose‐ und Poly(oxethylen)glucoseurethanenDurch Synthese von 3‐Isocyanato‐4‐methyl‐phenylcarbaminsäurealkylestern 1–5 mit Poly(oxethylen)sacchariden entstehen bisher unbekannte, grenzflächenaktive Poly(oxethylen)saccharose‐ und Poly(oxethylen)glucoseurethane 6–23.In Abhängigkeit von der Konzentration wurden die Oberflächenspannung und die Schaumfähigkeit dieser Verbindungen bestimmt und mit den Standards Na‐Dodecylsulfat und K‐Oleat verglichen.
Aldehyde, tert. Amine bzw. Acetale aus Amidacetalen und Grignardverbindungen
Authors: Walther H. , Haase L. , Gross H. , Costisella B. , Keitel I. 
Published: December 2004

Aldehydes, tert. Amines or Acetales from Amidacetales and Grignard‐CompoundsAmidacetales1or ‐mercaptales9respectively react with Grignard‐agents dependent on molar ratio by exchange of methoxy‐ or methylthio group via not isolable O,N‐ or S,N‐acetales to the corresponding aldehydes4or the tert. amines3. Starting from bicyclic amidacetales6aldehydes or bis‐β‐hydroxyethylamines8are formed. By quaternisation of the amidacetal‐nitrogen followed by reaction with Grignard‐agents the corresponding O,O‐acetales are formed.
Interpretation von Moleküldiagrammen freier π‐Radikalkationen — Naphthalen, Butadien, Styren, 1‐Methylstyren, 1,1′Diphenylethylen
Authors: Helmstreit W. , Hanschmann G. 
Published: December 2004

Interpretation of the MO‐diagrams of Free π‐Radical Cations — Naphthalene, Butadiene, Styrene, 1‐Methyl‐styrene, 1,1′‐DiphenylethyleneThe reactive and spectroscopic behaviour of the radical cations of the title compounds is discussed on the basis of general structural principles by means of molecular diagrams calculated with the PPP‐LHP‐SCF‐MO‐CI‐method. The greater reactivity of the monomer radicals compared with the dimers is due to the character of polymethene‐like compounds, whereas the lower reactivity of the dimer radicals cations can be ascribed to the more aromatic state of these species. The experimentally determined optical absorption maxima of the radical cations can be interpreted by the same classification.
Umsetzungen substituierter 1‐Thiochromone und 4(1H)‐Chinolone mit Nucleophilen
Authors: Rudorf W.‐D. , Augustin M. 
Published: December 2004

Reactions of Substituted 1‐Thiochromones and 4(1H)‐Quinolones with Nucleophiles1‐Thiochromone 1a and 4(1H)‐quinolone 1b react with nucleophiles to substitute the methylthio group. Compounds of type 1 are suitable C3‐fragments for the synthesis of novel heterocycles. Hydroxylamine leads to 2‐amino‐1‐thiochromone‐3‐carboxamide 7, whereas 1c gives 2‐methylthio‐1‐thiochromone‐oxime 8.
1H‐, 13C‐ und 15N‐NMR‐Untersuchungen an substituierten Thiadiazolen
Authors: Preiss A. , Walek W. , Dietzel S. 
Published: December 2004

1H‐, 13C‐ and 15N‐N.M.R.‐Studies on Substituted ThiadiazolesA number of substituted 1,2,4‐thiadiazoles, unlabelled and 15N‐labelled, were studied by 1H‐, 13C‐ and 15N‐ n.m.r. spectroscopy. The obtained n.m.r. data, especially the nitrogen‐15 chemical shifts and the 15N‐1H and 15N‐13C coupling constants allow to distinguish between isomeric forms and to determine the correct structure of each compound. So it was possible to come to conclusions about the formation mechanism of the investigated compounds.
Untersuchungen zum UV/Vis‐Spektralverhalten von Azofarbstoffen. V [16]. Quantitative Beschreibung der Absorptionsmaxima mehrfach substituierter Azobenzene mit einem Inkrementsystem
Authors: Mustroph H. , Epperlein J. 
Published: December 2004

Studies on U.V./vis Absorption Spectra of Azo Dyes. V. Quantitative Prediction of the Absorption Maxima of Polysubstituted Azobenzenes with an Increment SystemThe effect of substituents on the long‐wave band of azobenzenes can be described by using an increment system. Absorption increments which specifically characterize the substituents are derived from the difference in excitation energy between azobenzene and monosubstituted azobenzenes. Analysis of about 350 polysubstituted azobenzenes with absorption maxima between 320 nm and 650 nm showed that the differences between observed and calculated values are generally ±5 nm.Therefore, this increment system permits absorption maxima of azobenzenes to be deduced not as yet prepared or spectroscopically investigated.
Oxidative Kupplung CH‐acider Verbindungen mit p‐Phenylendiaminen. VII [1]. Synthese und oxidative Kupplung von 5‐Hydroxy‐naphth[2,1‐d]1,3‐oxathiol‐2‐onen
Authors: Mann G. , Wilde H. , Hauptmann S. , Naumann M. , Lepom P. 
Published: December 2004

Oxidative Coupling of CH‐acid Compounds with p‐Phenylenediamines. VII. Synthesis and Oxidative Coupling of 5‐Hydroxy‐naphth[2,1‐d] 1,3‐oxathiol‐2‐ones5‐Hydroxy‐naphth[2,1‐d]1,3‐oxathiol‐2‐ones with different substituents 1–21 were synthesized using the following procedures: Condensation of substituted naphthoquinones‐1,4 with thiourea (A); electrophilic substitution of 5‐hydroxy‐naphth[2,1‐d]1,3‐oxathiol‐2‐one (B); Fries‐reaction of 5‐acyloxy‐ and 5‐N‐phenylcarbamoyloxy‐naphth[2,1‐d]1,3‐oxathiol‐2‐ones (C). Oxidative coupling of the compounds with N,N‐diethyl‐quinone‐1,4‐diimine yielded thiazine dyes.
Cyclisierungsreaktionen β,γ‐ungesättigter Kohlensäurederivate. V . Reaktionen β,γ‐ungesättigter Carbamidsäureester mit Sulfenylchloriden ‐ Synthese von 3,5,5‐trisubstituierten Oxazolidin‐2‐onen
Authors: Mühlstädt M. , Widera R. , Olk B. 
Published: December 2004

Cyclization Reactions of β,γ‐Unsaturated Derivatives of Carbonic Acid. V. Reactions of β,γ‐Unsaturated Carbamic Acid Esters with Sulfenyl Chlorides — Synthesis of 3,5,5‐Trisubstituted Oxazolidine‐2‐onesN,N‐Disubstituted β,γ‐Unsaturated urethanes 1 have been cyclized to 3,5,5‐trisubstituted oxazolidine‐2‐ones 3 by aromatic sulfenyl chlorides in methylene chloride. The same oxazolidine‐2‐ones 3 were obtained by reaction of 5‐bromomethyloxazolidine‐2‐ones 8 with thiophenols.
A new ester component in the stobbe condensation. I. The condensation of some aromatic aldehydes with diethyl β,β‐dimethylglutarate
Authors: El‐Newaihy M. F. , Salem M. R. , Enayat E. I. , El‐Bassiouny F. A. 
Published: December 2004

Eine neue Esterkomponente in der Stobbe‐Kondensation. I. Kondensation einiger aromatischer Aldehyde mit Diethyl‐β,β‐dimethylglutaratKondensation von Benzaldehyd und p‐Anisaldehyd mit Diethyl‐β,β‐dimethylglutarat in Gegenwart von Natriumhydrid ergibt die kristallinen (Z)‐Halbester (1a und b) und ölige Halbesterfraktionen, die die E‐Isomeren 2a und b enthalten.Im Falle von p‐Chlorbenzaldehyd werden die (Z)‐ und (E)‐Halbester (1c und 2c) in reiner kristalliner Form erhalten. Die Konfiguration wurde durch Cyclisierung der entsprechenden Anhydride 3 zu den Oxoindenylcarbonsäuren 5 bestimmt.
Epoxid‐Reaktionen. V. Untersuchung von Teilreaktionen der Epoxidharz‐ Vorprodukt‐bildung durch chromatographische Methoden
Authors: Fedtke M. , Tänzer W. 
Published: December 2004

Epoxide Reactions. V. Chromatographic Studies of Some Reactions Involving Epoxide FormationsA reverse phase liquid chromatographic method has been applied for the quantitative determination of some products in epoxide forming reactions. The reaction of chlorohydrinethers of bisphenol A with aqueous sodium hydroxide has been studied quantitatively under different conditions.The influence of side products originating from epichlorohydrin on the course of the main reaction is discussed.In addition preparative liquid chromatographic methods have been developed to separate epoxide oligomers and some chlorohydrinethers of bisphenol A.
Zur heterogenkatalytischen Oxydation und Ammoxydation von Isobuten. IV. Über die Beeinflussung der heterogenkatalytischen Oxydation von Isobuten zu Methacrolein durch n‐Buten
Authors: Freiberg J. , Herrmann J. , Seeboth H. 
Published: December 2004

On the Heterogeneous‐Catalytic Oxidation and Ammoxidation of Isobutene. IV. Influence of n‐Butene on the Heterogeneous‐Catalytic Oxidation of Isobutene to MethacroleineThe influence of n‐butenes 2 on the oxidation of isobutenes 1 to methacroleine 3 has been investigated in presence of a catalyst containing Bi, Mo, P, Fe, Mg, Mn, Si and O. Addition of 2 to the gas mixture increase the selectivity and yield of 3. This fact can be correlated by decrease of oxygen partial pressure in consequence of the dehydrogenation of 2 to butadiene 4.