Spektroskopische Studien an O-Heterocyclen

Ledwoch, Klaus‐Dietrich

doi:10.1007/bf00468112

Cited by 6 publications

(1 citation statement)

References 4 publications

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“…The bands at 1180, 1135, 1070, and 1020 cm-I seem to relate to C-0-C-0-C stretching vibrations. 20 The most interesting change appeared in the region of the skeletal vibrations.…”

Section: Infrared Spectra Of Poly(viny1 Formal) and Model Formalsmentioning

confidence: 99%

High‐resolution proton magnetic resonance and infrared spectra of poly(vinyl formal) and its model compounds

Shibatani¹,

Fujiwara²,

Fujii³

1970

J. Polym. Sci. A‐1 Polym. Chem.

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High‐resolution proton magnetic resonance and infrared spectra of poly(vinyl formal) were studied in comparison with those of the model formals obtained from stereoisomers of pentane‐2,4‐diol and heptane‐2,4,6‐triol in order to learn spectral changes due to differences of the steric structures of the polymer. In the NMR spectrum of transformal obtained from dl diol or dl,dl (syndiotactic) triol, all proton signals were well interpreted by assuming a rapid chair‐chair inversion of the formal ring. On the other hand, no such inversion was observed spectroscopically in cis‐formal obtained from the meso diol or meso,meso (isotactic) triol, and the cis‐formal ring was supposed to take a diequatorial form preferentially. Consequently, dioxymethylene protons gave a single peak (equivalent) in trans‐formal and an AB quartet (nonequivalent) in cis‐formal. In the spectra of poly(vinyl formal), the dioxymethylene signal was an overlap of the singlet and quartet in dimethylsulfoxide solution. Observations of the spectra of various poly(vinyl formals) obtained from poly(vinyl alcohols) of different tacticities and study of temperature dependence of the signal have shown that the singlet and quartet are attributed to trans‐ and cis‐ formals, respectively, in the polymer spectrum also. In the infrared spectra of poly(vinyl formals), the 800 and 785 cm‐1 bands were found to be related to cis‐ and trans‐formal rings respectively. A linear relationship was confirmed between D785/D800 and trans/cis ratios determined from the peak intensities of the dioxymethylene proton signals.

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“…The bands at 1180, 1135, 1070, and 1020 cm-I seem to relate to C-0-C-0-C stretching vibrations. 20 The most interesting change appeared in the region of the skeletal vibrations.…”

Section: Infrared Spectra Of Poly(viny1 Formal) and Model Formalsmentioning

confidence: 99%

High‐resolution proton magnetic resonance and infrared spectra of poly(vinyl formal) and its model compounds

Shibatani¹,

Fujiwara²,

Fujii³

1970

J. Polym. Sci. A‐1 Polym. Chem.

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2,6,8‐trioxaspiro(3,5)nonane preparation, polymerization and polymer propertiess

Watanabe

Sugihara

1966

Makromol. Chem.

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I n this paper are described the preparation of 2,6,8-trioxaspiro(3,5)nonane (I) which has two different and polymerizable rings in one molecule, its cationic polymerization, and some properties of the polymer. I was prepared by tha action of sodium hydroxide on 5-bromomethyl-5-hydroxymethyl-1,3-dioxan~ which was obtained from pentaerythritol monobromide and paraformaldehyde in the presence of hydrochloric acid. The polymerization of I was carried out in methylene chloride by using BF,.(C,H,),O as a catalyst, giving highly crystalline polymers (m.p., 220-225OC.). The results of IR-analysis of the polymer, together with its solubility and melting properties, indicated that the polymerization occurred primarily through ring opening of the oxetane ring in the monomer without appreciable extent of cross-linking by opening of the 1,3-dioxan ring. The thermal stability of the polymer was examined both in air and nitrogene atmosphere. 5-Methylene-1,3dioxan besides formaldehyde was detected in the pyrolysis products, the formation of which was reasonably explainable by the cleavage of the main chain of the polymer through the so-called @-scission mechanism. ZUSAMMENFASSUNG: 2,6,8-Trioxaspiro(3,5)nonan (I), welches swei verschiedene polymerisierbare Ringe pro Molekiil enthiilt, wurde mittels NaOH aus 5-Brommethyl-5-hydroxymethyl-1,3-dioxan dargestellt ; letzteres ist aus Pentaerythritmonobromid und Paraformaldehyd in Gegenwart von HCl zuganglich. Bei der kationischen Polymerisation von I in Methylenchlorid mit BF, * O(C,H,), als Initiator wurden hochkristalline Polymere vom Schmelzbereich 220-225OC erhalten. Aus den IR-Spektren sowie aus Loslichkeit und Schmelsverhalten wird geschlossen, da13 die Polymerisation ganz iiberwiegend durch offnung des Oxetan-Ringes, ohne merkliche Vernetzung durch offnung des 1,3-Dioxanringes erfolgt. Die thermische Stabilitat des Polymeren wurde sowohl in Luft als aueh in Stickstoff gepriift. Neben Formaldehyd wurde 5-Methylen-1,3-dioxan in den Pyrolyseprodukten identifiziert ; letzteres ist vermutlich durch eine radikalische Kettenspaltung nach dem sogenannten p-Spaltungsmechanismus entstanden.

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Über die Herstellung cyclischer Acetale

Farwick

Raue

1967

J. Prakt. Chem.

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Durch Umsetzung des 1,1,1‐Tris‐hydroxymethyl‐propans und des in der Literatur noch nicht bekannten 1‐Chlormethyl‐1, 1‐bis‐hydroxymethyl‐propans mit einigen aliphatischen Aldehyden sowie Benzaldehyd durch normale säurekatalysierte Acetalisierung wurden einige cyclische Acetale (1,3‐Dioxane) dargestellt. Die Aufarbeitungsmethoden zur Reinstdarstellung dieser Verbindungen konnten wesentlich vereinfacht werden. Die Ausbeuten waren dabei in nahezu allen Fällen fast quantitativ. Es konnten neun neue Verbindungen charakterisiert werden.

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Spektroskopische Studien an O-Heterocyclen

Cited by 6 publications

References 4 publications

High‐resolution proton magnetic resonance and infrared spectra of poly(vinyl formal) and its model compounds

High‐resolution proton magnetic resonance and infrared spectra of poly(vinyl formal) and its model compounds

2,6,8‐trioxaspiro(3,5)nonane preparation, polymerization and polymer propertiess

Über die Herstellung cyclischer Acetale

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