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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 1198-1206 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Ozonolysis of Alkyliden- and BenzylidenadamantanesFrom the adamantane derivatives 4-7 normal ozonides could be obtained by treatment with ozone in pentane. The olefines 9 and 10 do not react with ozon. Methanol and tetracyanoethylene respectively interfere in the known manner. 4 and 8 form primary ozonides, which are stable at -78°C.
    Notes: Die Adamantanderivate 4-7 geben bei der Ozonbehandlung in Pentan normale Ozonide, während die stark sterisch gehinderten Olefine 9 und 10 nicht mit Ozon reagieren. Sowohl Methanol wie Tetracyanäthylen greifen in bekannter Weise in die Ozonolyse ein. Nur bei der Ozonisierung von 4 und 8 konnten bei -78°C Primärozonide nachgewiesen werden.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 1642-1654 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Intramolecular Competition during the Ozonolysis of Substituted CyclopentenesThe ozonolysis of 1,2-dimethyl- or 1,2-diphenyl-1-cyclopentenes containing different substituents in 4-position produces carbonyl oxides as intermediates. These can react with each of two functional groups. The order of 1,3-dipolarophilic activity decreases in the order formyl ≫ acetyl 〉 benzoyl. The formation of cyclobutene ozonides predominates over that of cyclopentene ozonides. An alcoholic group in a favourable position adds much faster to a carbonyl oxide group than does an acetyl group. Reduction of the different ozonides leads to triketones or to trioxa-adamantanes.
    Notes: Die Ozonolyse von 1,2-Dimethyl-bzw. 1,2-Diphenyl-1-cyclopentenen mit 4-ständigen funktionellen Gruppen führt intermediär zu Carbonyloxiden, denen zur Weiterreaktion jeweils zwei Gruppen zur Auswahl stehen. Deren 1,3-dipolarophile Wirksamkeit fällt in der Reihenfolge Formyl- ≫ Acetyl- 〉 Benzoylgruppe ab. Die Bildung von Cyclobuten-ozoniden ist vor derjenigen der Cyclopenten-ozonide stark bevorzugt. Eine alkoholische Gruppe in günstiger Stellung addiert sich weit schneller als eine Acetylgruppe. Als Reduktionsprodukte der Ozonide werden Triketone oder Trioxa-adamantane erhalten.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 108 (1975), S. 1207-1217 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structure and Kind of Formation of the Ozonides of Bis-adamantylidene and Bis-bicyclo[3.3.1]non-9-ylideneThe treatment of the title compounds with ozone in pentane leads mainly to the epoxides, but in addition to 33 and 18% respectively of O3-compounds. These, in spite of some unusual properties are normal ozonides, and there formation can only be explained by a strong 1,3-dipolarophilic character of adamantanon and bicyclo[3.3.1]nonan-9-on.
    Notes: Bei der Ozonbehandlung in Pentan geben die beiden Titelverbindungen hauptsächlich die Epoxide, daneben in 33- bzw. 18proz. Ausbeute O3-Verbindungen, für die trotz widersprüchlichen Verhaltens die Konstitution von normalen Ozoniden bewiesen werden konnte. Für die Bildung dieser tetrasubstituierten 1,2,4-Trioxolane ist eine besonders starke 1,3-Dipolarophilie von Adamantanon bzw. Bicyclo[3.3.1]nonan-9-on verantwortlich.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 116 (1983), S. 409-415 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Monoozonolysis of 2,3-Dimethylbutadiene in Pentane and in Methanol2,3-Dimethylbutadiene (1) was attacked predominantly at only one double bond by a deficient amount of ozone in pentane or in methanol. In pentane, an α,β-unsaturated ozonide (4) was formed, which was further converted into an α,β-dibromoozonide (2) and into an α,β-epoxyozonide (6), respectively. Ozonolysis of 1 in methanol afforded an α,β-unsaturated methoxy hydroperoxide (8) and formaldehyde as well as a joint coproduct (9) of the latter two fragments.
    Notes: 2,3-Dimethylbutadien (1) wurde von einem Unterschuß an Ozon in Pentan oder in Methanol überwiegend nur an einer Doppelbindung angegriffen. In Pentan entstand ein α,β-ungesättigtes Monoozonid (4), aus welchem ein α,β-Dibromozonid (2) und ein α,β-Epoxyozonid (6) hergestellt wurden. Ozonolyse von 1 in Methanol ergab ein α,β-ungesättigtes Methoxyhydroperoxid (8) und Formaldehyd sowie ein gemeinsames Folgeprodukt (9) dieser Fragmente.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 117 (1984), S. 2193-2204 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Halogen Epoxides, 7. Rearrangements during the Reaction of Substituted 2-Chloro- and 2,3-Dichlorooxiranes with Silver TetrafluoroborateReactions of tert-butyl-substituted and of isopropyl-substituted chlorooxiranes with silver tetrafluoroborate have been examined. Dehalogenations in the 2-positions of 2-chloro-2-tert-butyl- (5) and of 2-chloro-2-isopropyl-substituted oxiranes (35) occurred without changes of the carbon skeletons. By contrast, dehalogenations in the 2-positions of 2-chloro-3-tert-butyl- (12) and of 2-chloro-3-isopropyloxiranes (35) afforded partly rearranged products by 1,2-methyl- and/or 1,2-hydride shifts to the corresponding α-ketocarbenium ions.
    Notes: Umsetzungen von tert-butylsubstituierten und von isopropylsubstituierten Chloroxiranen mit Silbertetrafluoroborat wurden untersucht. Reaktionen, welche durch Enthalogenierung in der 2-Position von 2-Chlor-2-tert-butyl- (5) bzw. von 2-Chlor-2-isopropyloxiranen (35) verliefen, ergaben keine Veränderungen der C-Gerüste. Reaktionen, welche durch Enthalogenierung in der 2-Position von 2-Chlor-3-tert-butyl- (12) bzw. von 2-Chlor-3-isopropyloxiranen (35) verliefen, ergaben dagegen teilweise umgelagerte Produkte durch 1,2-Methyl- bzw. 1,2-Hydridverschiebungen an den intermediären α-Ketocarbenium-Ionen.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The anionic ring-opening polymerization of mixtures of 2,2-dimethyltrimethylene carbonate and ∊-caprolactone in toluene as solvent, with sec-butyllithium or potassium dihydronaphthylide as initiator, results in the formation of polymers of the (A-X-B)n type, where A represents a poly(2,2-dimethyltrimethylene carbonate) block, B represents a poly(∊-caprolactone) block and X stands for a block of the two monomers with a composition gradient; n represents the number of portions by which the monomer mixture is added to the initiator or the living system. From the time-conversion curves it follows that the reactivity of the carbonate monomer is higher than that of the lactone. This difference in reactivity of the monomers is the reason for the special polymer architecture represented by (A-X-B)n. The properties of these polymers depend upon the ratio of the monomers and the number n of additions. The polymers are characterized by spectroscopic, thermoanalytical, and thermomechanical measurements.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 191 (1990), S. 1165-1175 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Attempts of anionic ring-opening polymerization of benzo-1,3-dioxolan-2-one (1) with sec-butyllithium or potassium dihydronaphthylide as initiators in different solvents and under a variety of reaction conditions revealed that this monomer cannot be polymerized. Possible reasons for this finding are discussed. Benzo-1,3-dioxan-2-one (2) was prepared and characterized for the first time. Anionic ring-opening polymerization of this monomer yields a polymer with a non-uniform constitution, viz., loss of carbon dioxide occurs during polymerization. The mechanism of formation of this polymer is discussed on the basis of product analysis and analysis of the active species formed during polymerization. Attempts to synthesize 5,6-benzo-1,3-dioxepan-2-one (3) failed.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The anionic ring-opening polymerization of mixtures of 2,2-dimethyltrimethylene carbonate (5,5-dimethyl-1,3-dioxan-2-one) (1) and pivalolactone (2,2-dimethyl-3-propanolide) (3) in toluene as a solvent and with potassium dihydronaphthylide as initiator, results in formation of block copolymers with yields of ca. 90%. In tetrahydrofuran as a solvent the polymer yields are ca. 65% only. In toluene, 1 polymerizes first and subsequently 3 resulting in a blocky structure of the copolymer. According to a mechanistic study, the active species is first a 1-alcoholate, later a 3-alcoholate and finally a 3-carboxylate. The copolymers are soluble in deuterochloroform up to a mole fraction of pivalolactone of ca. 0,40. By means of 13C NMR spectroscopy the blocky structure of the copolymers prepared in toluene was confirmed. In tetrahydrofuran as a solvent 1-3 and 3-1-diads are formed to a significant extent. The copolymers were characterized by thermoanalytical and thermomechanical measurements.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The miscibility of poly(2,6-dimethylphenylene oxide) (PPO) with polystyrene-block-poly(2,2-dimethyltrimethylene carbonate) (PS-block-PDTC) was studied and compared with the corresponding PPO/PS blends. PPO/PS-block-PDTC blends show two thermal transitions in the temperature range investigated; that is the melting of the DTC block and the glass transition of the mixed PPO/PS block phase. The Tg values obtained are discussed by means of the Fox and Gordon-Taylor equation. The influence of the PDTC block leads to higher Tg values of the PPO/PS block mixture than of the corresponding homopolymer blend.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The anionic ring-opening polymerization of ε-caprolactone and 2,2-dimethyltrimethylene carbonate in toluene as solvent with polystyryllithium or lithium polystyrylethoxide resp. lithium polystyrylmethoxide as initiators, results in the formation of the corresponding block polymers as major products, beside small amounts of homopolymer. The block copolymers were isolated chromatographically from the mixture and analyzed spectroscopically.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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