Friedrich Boberg
Hochschule Hannover
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Sulfur Reports | 1983
Claus-Detlef Czogalla; Friedrich Boberg
Abstract Fossil fuels and products made from them vary in sulfur content according to different origins and refining operations. The following sulfur contents are known: 0.05–13.95% for crude oils1, 0.2–12% for oil shales2,16, 0.4–11.5% for tar sands3 and 0.03–1% for syncrudes from coals4.5. The low sulfur contents of syncrudes from coals originate in the hydrogenation processes by which the coals are liquefied and at the same time partially desulfurized.
Phosphorus Sulfur and Silicon and The Related Elements | 1988
Claus-Detlef Czogalla; Friedrich Boberg
Abstract Starting with methylene ketones 2,5-diphenylthiophenes and b,d-anellated thiophenes are prepared. Aus Methylenketonen werden 2,5-disubstituierte und b,d-anellierte Thiophene hergestellt.
Phosphorus Sulfur and Silicon and The Related Elements | 1983
Friedrich Boberg; Udo Puttins; Wolfgang Schmidt; Karl-Franz Torges
Abstract Starting with arylmethylketones a general method to methyl 3,5-diaryl-2,4-thiophenedicarboxylates is described. Aryl is phenyl, p-tolyl, 1- and 2-naphthyl and 2-thienyl. Intermediates are aryl substituted sulfur heterocycles: 1,2-dithiol-3-thiones, 1,2-dithiol-3-ones, 4-bromo-1,2-dithiol-3-ones and dimethyl 1,4-dithiin-2,5-dicarboxylates. Alcaline saponification of the dimethyl esters gives 3,5-diaryl-4-methoxy-carbonyl-2-thiophenecarboxylic acids and after that the dicarboxylic acids. Ausgehend von Arylmethylketonen wird ein allgemeiner Syntheseweg zu 3,5-Diaryl-2,4-thiophendicar-bonsauredimethylestern beschrieben. Aryl ist Phenyl, p-Tolyl, 1- und 2-Naphthyl und 2-Thienyl Zwischenstufen sind arylsubstituierte Schwefelheterocyclen: 1,2-Dithiol-3-thione, 1,2-Dithiol-3-one, 4-Brom-1,2-dithiol-3-one und 1,4-Dithiin-2,5-dicarbonsauredimethylester. Alkalische Verseifung der Diester liefert 3,5-Diaryl-4-methoxycarbonyl-2-thiophencarbonsauren, die weiter zu den Dicarbonsauren verseift werden.
Phosphorus Sulfur and Silicon and The Related Elements | 1989
Friedrich Boberg; Bernd Bruchmann; Gunter Nink; Alfons Garming
Abstract N-Substituted 2- and 4-pyridinethiones A react with sodium-N-chlorobenzenesulfonamides 1 to N-phenylsulfonyl-S-pyridylidenesulfimides B, N,N′-bis(phenylsulfonyl)-S-pyridiniosulfodiimidates C and N-pyridylidenebenzenesulfonamides D. The constitution of the new pyridiniosulfodiimidates C is proved by X-ray crystal structure of one compound C and by 1H-NMR-spectra of all 1-methylpyridinio-compounds C, which have a downfield shift for the N-methyl-δ-values. Formation, stabilities, IR-, 1H-NMR-spectra and bond systems of A-D are discussed. N-Substitutierte 2- und 4-Thiopyridone A reagieren mit Natrium-N-chlorbenzolsulfonamiden 1 zu N-Phenylsulfonyl-S-pyridylidensulfimiden B, N,N′-Bis(phenylsulfonyl)-S-pyridiniosulfodiimidaten C und N-Pyridylidenbenzolsulfonamiden D. Konstitutionsbeweise fur die neuen Pyridiniosulfodiimidate C sind die Rontgenstrukturanalyse eines Vertreters und die 1H-NMR-Spektren der N-Methylpyridinioverbindungen C mit δ-Werten fur die N-Methylgruppe bei tiefem Feld. Fur A-D werden d...
Phosphorus Sulfur and Silicon and The Related Elements | 1992
Friedrich Boberg; Wolfgang Bruns; Dagmar Mußhoff
Abstract The preparation of all position isomeres of dibenzothiophenes with a linear C1[sbnd]C5-sidechain and of the corresponding 5,5-dioxides is described. 1H-NMR-data and GC-purities are given. Die Darstellung von allen stellungsisomeren Dibenzothiophenen mit einer unverzweigten C1[sbnd]C5-Seitenkette und der zugehorigen 5,5-Dioxide wird beschrieben. 1H-NMR-Daten und GC-Reinheiten werden gebracht.
Phosphorus Sulfur and Silicon and The Related Elements | 1992
Friedrich Boberg; Adam Jachiewicz; Alfons Garming
Abstract A one pot synthesis gives methyl-5,6,7,8-tetrahydrodinaphtho[1,2-b:2′,1′-d]thiophenes (7) from methyl-1,2,3,4-tetrahydronaphthalen-1-ones (1) by bromination and sufurization. Tetrahydro compounds 7 have been dehydrogenated to corresponding dinaphtho[b,d]thiophenes 8. Proofs for the constitutions are nmr data of 7, 8 and the independent synthesis of one compound 8. A reaction mechanism with 1,4-dithiine intermediates is discussed. Eine Eintopfsynthese liefert Methyl-5,6,7,8-tetrahydrodinaphtho[1,2-b:2′,1′-d]thiophene (7) aus Methyl-1,2,3,4-tetrahydro-naphthalin-1-onen (1) durch Bromierung und Schwefelung. Tetrahydroverbindungen 7 werden zu entsprechenden Dinaphtho[b,d]thiophenen 8 dehydriert. Konstitutionsbeweise sind NMR-Daten von 7, 8 und die unabhangige Synthese einer Verbindung 8. Ein Reaktionsmechanismus mit 1,4-Dithiin-Intermediaten wird diskutiert.
Phosphorus Sulfur and Silicon and The Related Elements | 1991
Gunter Nink; Friedrich Boberg
Abstract The oxidation of b,d-anellated thiophenes with aromatic and nonaromatic rings gives sulfones and other products, depending on the anellated rings. Oxidants are H1O2 and MCPBA. Die Oxidation von b,d-anellierten Thiophenen mit aromatischen and nichtaromatischen Ringen fuhrt zu Sulfonen and anderen Produkten, in Abhangigkeit von den anellierten Ringen. Oxidationsmittel sind H2O2 and MCPBA.
Phosphorus Sulfur and Silicon and The Related Elements | 1987
Friedrich Boberg; Andrea Paetz; Bernd Bruchmann; Alfons Garming
Abstract N-(2-Pyridylthio)amides 7 and salts of them have been prepared from 2-thiopyridone (1) with sodium-N-chloro-or N′N-dichlorobenzenesulfonamides (3 or 4), N-chloro-or N,N-dichloro-o-nitrobenzamide (2e or 4e), N-chloro or N,N-dichloroethylurethane (2f or 4f). Reactions of different amides 7 and the 13C-and 15N-NMR-spectra of N-(2-pyridylthio)-p-toluenesulfonamide (7b) prove the constitutions. N-(2-Pyridylthio)amide 7 und deren Salze werden dargestellt aus 2-Thiopyridon (1) mit Natrium-N-chlor-oder N,N-Dichlorbenzolsulfonamiden (3 oder 4), N-Chlor-oder N,N-Dichlor-o-nitrobenzamid (2e oder 4e), N-Chlor-oder N,N-Dichlorethylurethan (2f oder 4f). Reaktionen verschiedener Amide 7 und die 13C-und 15N-NMR-Spektren des N-(2-Pyridylthio)-p-toluolsulfonamids (7b) beweisen die Konstitutionen.
Phosphorus Sulfur and Silicon and The Related Elements | 1992
Friedrich Boberg; Wolfgang Bruns; Rose Kaller; Dagmar Mußhoff
Abstract The preparation of all positional isomers of dibenzothiophenes with one isopropyl- or tert-butyl-group, of 2-isobutyldibenzothiophene, 3-neopentyldibenzothiophene and of all corresponding 5,5-dioxides is described, 1H-NMR-data and GC-purities are given. Die Darstellung von allen stellungsisomeren Dibenzothiophenen mit einem Isopropyl- oder tert-Butyl-Rest, von 2-Isobutyldibenzothiophen, 3-Neopentyldibenzothiophen und von allen zugehorigen 5,5-Dioxiden wird beschrieben. 1H-NMR-Daten und GC-Reinheiten werden gebracht.
Phosphorus Sulfur and Silicon and The Related Elements | 1984
Friedrich Boberg; Udo Puttins
Abstract Depending on the functional groups derivatives of the 2,4′:2′,2″-terthiophene-3′,5′-dicarboxylic acid (1) react to cyclopenta[b]- or cyclopenta[c]thiophenes: With identical functional groups in 3′- and 5′-position the cyclopenta[b,c′]dithiophene system 3 is formed, however with a more reactive group in the 5′-position the cyclopenta[b,b′]dithiophene system 2 is formed. In alcaline medium the cyclopentadienone ring of the cyclopenta[b,b′]dithiophenone 2b is cleaved leading to 3′-methoxycarbonyl-2,4′:2′,2″-terthiophene-3-carboxylic acid (6b). Ring closure with 7-oxo-2-(2-thienyl)-cyclopenta[b,b′]dithiophene-3-carbonylchloride (2c) or double ring closure with 2,4′:2′,2″-terthiophene-3,3′-dicarbonyldichloride (6c) gives 4,9-bis(thieno[2′,3′:5,4]cyclopenta)[1,2-b:1,2-d]thiophendione (4). The structures of the systems 1–4 and 6 are proved by chemical and spectroscopic facts. Derivate der 2,4′:2′,2″-Terthiophen-3′,5′-dicarbonsaure (1) reagieren in Abhangigkeit von den funktionellen Gruppen zu Cyclopenta...