Search results for "Chloride"
showing 10 items of 1691 documents
1982
N-Ethylaziridine (1) was polymerized in water with HCl as initiator and copolymerized with N-(2-hydroxyethyl)aziridine (2). Rapid propagation and termination reactions were observed. The maximum yield increases with the initiator concentration, whereas the molecular weight decreases. This is due to the difference in basicity between the tertiary N-atoms of the two monomers and the tertiary and the terminal secondary N-atoms of the polymers, which causes tranfer and termination reactions. Macrocycles with a side chain on a quaternary N-atom are formed. During the copolymerization, the more basic 1 is preferentially incorporated into the copolymer chain. The copolymerization parameters can be…
Solid-Phase Synthesis of Oligo(p-benzamide) Foldamers
2006
[reaction: see text] A coupling protocol has been developed which allows the synthesis of oligo(p-benzamide)s on solid support. Aromatic carboxylic acids are activated in situ with thionyl chloride and used to acylate secondary aromatic amines. N-p-Methoxy benzyl (PMB) as well as N-hexyl protected monomers were investigated. Heterosequences of both monomers were synthesized. Such nanoscale objects are important building blocks for supramolecular chemistry.
Polymere 3-acryloyloxyalkyl- und 3-acryloyloxyaryl-4-thiazolidone als strahlenschutzsubstanzen
1977
The syntheses of 3-acryloyloxyalkyl- and 3-acryloyloxyaryl-2-phenyl-4-thiazolidones (3a–c) from the corresponding hydroxyl derivatives 2a–c and acrylic acid chloride are described. These monomers were homopolymerized and copolymerized with N-vinyl-2-pyrrolidone by radical initiation. The resulting water soluble copolymers were tested in animals for radioprotective activity and prolongation of efficiency.
Über die Darstellung und Polymerisation von 4-Vinyldiphenyl, 11-Vinyl-p-terphenyl und 1 2-Vinyl-p-terphenyl
1969
Fur die Darstellung von 4-Vinyldiphenyl und 11-Vinyl-p-terphenyl wurden einfache, verallgemeinerungsfahige Synthesen ausgearbeitet. Durch Umsetzung entsprechender Carbinole mit Methansulfonsaurechlorid in Pyridin gelang die Darstellung der Vinylverbindungen in einer einstufigen Reaktion. Die Untersuchung der radikalischen Copolymerization der Monomeren mit Styrol ergab bei 4-Vinyldiphenyl und 12-Vinyl-p-terphenyl einen bevorzugten Einbau in die Polymerketten, wahrend 11-Vinyl-p-terphenyl nur in untergeordnetem Mase in Polystyrolketten eingebaut wurde. The synthesis of 4-vinylbiphenyl and 11-vinyl-p-terphenyl was performed by a simple synthetic route. By reaction of the corresponding alcohol…
Anorganische verbindungen als lösungsmittel für polymere und monomere. Polymerisationen in phosphoroxychlorid und thionylchlorid
1966
Die Loslichkeit verschiedener Monomerer, Polymerer und Polymerisationskatalasatoren in anorganischen Verbindungen wurde untersucht. Chloride und Oxychloride des Phosphors und Schwefels zeigten gute Losungseigenschaften. Thionylchlorid und Phosphoroxychlorid wurden als Losungsmittel bei der kationischen Polymerisation von Styrol, Isobutylvinylather, 3,3-Bis-(chlormethyl)-oxetan, Tetrahydrofuran und Epichlorhydrin eingeaetzt. Als geeignete Katalysatoren erwiesen sich hierbei Aluminiumchlorid und Eisentrichlorid. In Phosphoroxychlorid konnten Acrylnitril und Vinylchlorid radikalisch polymerisiert werden. The solubility of a series of monomers, polymers, and initiators in inorganic compounds wa…
Die Kationische ɛ-Caprolactam-Polymerisation. V. Die quantitative Bestimmung der N-Acyllactam-Gruppen bei der Initiierung mit wasserfreien Säuren und…
1971
Als Beitrag zur Aufklarung des Mechanismus der kationischen Caprolactam-Polymerisation mit wasserfreien Sauren (z. B. HCl) als Initiatoren wurde der Gehalt der C-terminal entstehenden N-Acyllactam-Endgruppen und anderer funktioneller Gruppen der gebildeten Oligo- und Polyamide quantitative bestimmt. Dies erfolgte auf IR-spektroskopischem Wege und durch potentiometrische Titration der nach alkalischer Hydrolyse gebildeten Carboxylgruppen. Fur die Polymerisation wurde ein verbessertes Verfahren ausgearbeitet, das vollstandigen Sauerstoff- und Feuchtigkeitsausschlus ermoglicht und damit besser reproduzierbare Ergebnisse liefert. Die Abhangigkeit der Konzentration verschiedener funktioneller Gr…
1980
STUDIEN ZUM VORGANG DER WASSERSTOFFÜBERTRAGUNG 611
1982
Abstract In arylsulfonyl halides, the half-wave potentials of the corresponding chlorides and fluorides differ by more than 1000 mV, the fluoride being more negative; the influence of para-substituents is small for the chlorides, large for the fluorides. In agreement with the half-wave potentials, arylsulfonyl chlorides are considerably more reactive chemically than the corresponding fluorides. The O-selectivity found for P(O)F compounds is not observed in arylsulfonyl fluorides. Studies of competitive ester formation using primary and secondary alcohols and various arylsulfonyl chlorides yielded no clear analogy to the half-wave potentials. The primary alcohol is always sulfonated in prefe…
Low-lying Rydberg states of HCl.
2008
Vertical excitation energies belonging to some different Rydberg series of hydrogen chloride have been determined with a coupled-cluster theoretical approach. These excitation energies have allowed us to calculate electric dipole transition intensities in HCl and allow additional assessment of the calculation approach presently used to provide an adequate description of the valence and Rydberg states of HCl. The molecular quantum defect orbital has been applied to the calculation of oscillator strengths. In particular, new insight is given on the assignment of states as the R1Pi, the 1Delta(4dpi and 5ppi), the 1Sigma+(4dpi), and the nddelta(1Pi, 1Phi) and 4f states.
Synthesis of new 2,2′-disubstituted 5,5′-dimethyl-4,4′-bitriazoles and 2-(4-Triazolyl)quinoxalines
2000
Thermal rearrangement of 3-acylisoxazole arylhydrazones allowed facile preparation of 2H-1,2,3-triazoles which were firstly reacted with isoamyl nitrite and then with an opportune arylhydrazine to produce the corresponding α-hydroxyiminohydrazones 8a-h. The reaction of compounds 8a-h with phosphorus pentachloride afforded the desired 4,4′-bitriazoles 1a-h. The α-hydroxyiminoketone derivative 7 or the α-diketone 14 reacted easily with 1,2-phenylenediamine to afford 1,2,3-triazoles 2a-c bearing the quinoxaline moiety at position 4. Improved yields of the quinoxalines 2a-c were obtained when 1,2-phenylenediamine was reacted with the dioxime 15.