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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 2298-2304 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Condensed Ring Systems, IV. Synthesis and Spectroscopic Properties of Dithia- and Oxathia-propellanesThe synthesis of 8,11-dithia- (1, n-4) and 8-oxa-11-thia[4.3.3]propellane (2, n = 4) as well as of 9,12-dithia- (1, n-5) and 9-oxa-12-thia[5.3.3]propellane (2, n = 5) is reported. The n.m.r. spectra of the dithia- (1, n = 1-5) and oxathia-propellanes (2, n-1-5) known to date are compared an discussed.
    Notes: Die Synthese des 8,11-Dithia- (1, n-4) and 8-Oxa-11-thia[4.3.3]propellane (2, n = 4) sowie des 9,12-Dithia- (1, n-5) und 9-Oxa-12-thia[5.3.3]propellans (2, n = 5) wird beschrieben. Die NMR-Spektren (Abb. 1 und 2) der bisher bekannten Dithia- (1, n = 1-5) und Oxathia-propellane (2, n = 1-5) werden verglichen und diskutiert.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 1925-1930 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Condensed Ring Systems, VII. Synthesis of 8-Hetero[4.3.2]propell-10-enesThe Ramberg-Bäcklund reaction with α-chlorosulfones 2a and b and 5a and b leads to 8-oxa[4.3.2] propell-10-ene (3) and 8-thia [4.3.2]propell-10-ene 8,8-dioxide (6), respectively. The yields of 3 and 6 are substantially higher than those of [4.2.2]propella-7,9-diene1) prepared by double Ramberg-Bäcklund reaction. This can be explained by an increase in conformational mobility of the propellane skeleton with an increase in the size of the ring system and by the extent to which bond angles are deformed in the products. In the case of rigid ring systems the elimination reaction which leads to cyclobutene ring formation is accompanied by a competing reaction in which chlorine is replaced by the attacking base. In this way 4 is obtained as a side product of the synthesis of 3.
    Notes: Durch Ramberg-Bäcklund-Reaktion an den α-Chlorsulfonen 2a und b bzw. 5a und b werden das 8-Oxa[4.3.2]propell-10-en (3) bzw. 8-Thia [4.3.2]propell-10-en-8,8-dioxid (6) hergestellt. Die Ausbeuten an 3 und 6 sind wesentlich höher als die an dem durch doppelte Ramberg-Bäcklund-Reaktion hergestellten [4.2.2]Propella-7,9-dien1). Ursache dafür ist die zunehmende Konformative Beweglichkeit des Propellangerüstes mit größer werdendem Ringsystem und die Winkelverzerrung in den Endprodukten. Als Konkurrenzreaktion bei den starren Ringsystemen tritt neben der Eliminierung zum Cyclobutenring Substitution des Chlors durch die angreifende Base auf. So erhält man bei der Synthese von 3 als Nebenprodukt das substitutionsprodukt 4.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Condensed Ring Systems, XIII. Elucidation of Constitutions and Configurations of Isomeric Dichlorodithiapropellane Tetroxides with the Aid of 13C NMR SpectroscopyDithiapropellanes 1 with n 〉 1 can be converted to the isomeric dichlorodithiapropellane tetroxides 2 (n = 2-5), while 1 with n = 1 decomposes under identical reaction conditions. Even mild oxidation of 3,7-dithia[3.3.1]propellane (1, n = 1) with hydrogen peroxide in glacial acetic acid at room temperature results in elimination of sulfur dioxide and isomerisation to 3,5-dimethylene-tetrahydrothiopyran-1,1-dioxide (5). The constitutions and configurations of the isomeric dichlorodisulfones 2 (n = 2-5) are elucidated with the aid of 13C NMR spectroscopy. - The dichlorodisulfones 2 can be converted to 1,4-polymethylene-Dewar benzenes 3 by a double Ramberg-Bäcklund reaction only if the saturated carbocycle contains at least four methylene groups.
    Notes: Aus den Dithiapropellanen 1 mit n 〉 1 lassen sich die isomeren Dichlordithiapropellantetroxide 2 (n = 2-5) herstellen, während sich 1 mit n = 1 unter den gleichen Reaktionsbedingungen zersetzt. Schon bei der gelinden Oxidation des 3,7-Dithia[3.3.1]propellans (1, n = 1) mit Wasserstoffperoxid in Eisessig bei Raumtemperatur bildet sich unter Abspaltung von Schwefeldioxid und Isomerisierung das 3,5-Dimethylen-tetrahydrothiopyran-1,1-dioxid (5). Die Konstitutionen und Konfigurationen der isomeren Dichlordisulfone 2 (n = 2-5) werden mit Hilfe der 13C-NMR-Spektroskopie aufgeklärt. - Die Dichlordisulfone 2 lassen sich durch doppelte Ramberg-Bäcklund-Reaktion nur dann in die 1,4-Polymethylen-Dewar-Benzole (3) überführen, wenn der gesättigte Carbocyclus mindestens vier Methylengruppen enthält.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 2305-2309 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Condensed Ring System, V. Synthesis and Spectroscopic Properties of cis- and trans- 1,5-Dimethyl-1,3,7-diheterobicycol-[3.3.0]octanesThe synthesis of 1,5-dimethyl-3,7-dithiabicyclo [3.3.0]octane yields the cis (4a) and the trans-isomer (5a) in a ratio of 1:1 Small amounts of the cis-(4b) and the trans-isomer (5b) of 1,5-dimethyl-3-oxa-7-thiabicyclo[3.3.0]octane are formed as side products. The configuration of the isomers can be deduced from their n.m.r. spectra by comparing the spectra with those of dihetero[3.3.n.]propellanes1) having cis-configuration.
    Notes: Bei der Synthese des 1,5-Dimethyl-3,7-dithiabicyclo[3.3.0]octans entstehen das cis (4a) und trans-Isomere (5a) im Verhältnis 1:1. Als Nebenprodukte erhält man in geringen Mengen das cis- (4b) und trans-Isomere (5b) des, 1,5-Dimethyl-3-oxa-7-thiabicyclo [3.3.0]octans. Der Vergleich ihrer 1H-NMR-Spektren mit denen der cis-konfigurierten Dihetero[3.3.n]propellane1) ermöglicht die Konfigurationszuordnung.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 109 (1976), S. 796-798 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 109 (1976), S. 793-795 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 1915-1924 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Condensed Ring Systems, VI. Synthesis of [4.2.2]Propella-7,9-diene, a Dewar Benzene Bridged in 1,4-PositionThe reaction of 8,11-dithia [4.3.3] propellane (1, n = 4) with N-chlorosuccinimide and monoperphthalic acid yields a mixture of four isomeric dichlorinated disulfones (2, n = 4). The major isomer 7 is formed in 40% yield. Upon treatment of 2 (n = 4) with potassium tert-butoxide at low temperatures [4.2.2] propella-7,9-diene2) (3, n = 4) is obtained. The constitution of 3 (n = 4) is deduced by 1H and 13C n. m. r as well as mass spectrometry.
    Notes: Die Umsetzung des 8,11-Dithia [4.3.3] propellans (1, n = 4) mit N-Chlorsuccinimid und Monoperphthalsäure führt zu einem Gemisch von vier isomeren dichlorierten Disulfonen (2, n = 4), von denen das Hauptprodukt 7 in 40proz. Ausbeute entsteht. 2 (n = 4) läßt sich mit Kalium-tert-butylat bei tiefen Temperaturen in das [4.2.2]Propella-7,9-dien2)(3, n = 4) überführen, dessen Konstitution durch die 1H-, 13C-NMR- und Massenspektren bewiesen wird.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 110 (1977), S. 2969-2977 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Condensed Ring Systems, XII. On the Influence of the Carbocycle on the Reaction Course of the Ramberg-Bäcklund Reaction of OxathiapropellanesBy modification of our previous specifications for the syntheses of dithiapropellanes, oxathiapropellanes 1-5 are synthesized on a preparative scale. The configurations of monochloro-oxathiapropellane dioxides 11-16 obtained from 2-5 are elucidated. The transformation of 11-16 into the analogous oxapropellenes 17-19 is dependent on the ring size of the carbocycles. 3-Oxa[3.3.2]propell-9-ene (17) is obtained in about 1% yield only, and thus represents the oxapropellene with the smallest carbocycle preparable by this synthetic route.
    Notes: Durch Abänderung unserer früheren Synthesevorschrift für die Dithiapropellane werden die Oxathiapropellane 1-5 in präparativem Maßstab hergestellt. Die Konfigurationen der aus 2-5 erhaltenen Monochloroxathiapropellandioxide 11-16 werden aufgeklärt. Die Überführung von 11-16 in die entsprechenden Oxapropellene 17-19 ist von der Ringgröße des Carbocyclus abhängig. Das 3-Oxa[3.3.2]propell-9-en (17) entsteht nur in ca. 1 proz. Ausb. und ist damit das Oxapropellen mit dem kleinsten Carbocyclus, das nach diesem Syntheseweg hergestellt werden kann.
    Additional Material: 1 Ill.
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