- Oxazine Ring-Related Vibrational Modes of Benzoxazine Monomers Using Fully Aromatically Substituted, Deuterated, 15N Isotope Exchanged, and Oxazine-Ring-Substituted Compounds and Theoretical Calculations
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Polymerization of benzoxazine resins is indicated by the disappearance of a 960-900 cm-1 band in infrared spectroscopy (IR). Historically, this band was assigned to the C-H out-of-plane bending of the benzene to which the oxazine ring is attach
- Han, Lu,Iguchi, Daniela,Gil, Phwey,Heyl, Tyler R.,Sedwick, Victoria M.,Arza, Carlos R.,Ohashi, Seishi,Lacks, Daniel J.,Ishida, Hatsuo
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p. 6269 - 6282
(2017/09/01)
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- Alkylation of amino acids and glutathione in water by o-Quinone methide. Reactivity and selectivity
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o-Quinone methide (1) has been produced in water both thermally and photochemically from (2-hydroxybenzyl)trimethylammonium iodide (2). Michael addition reactions of 1 to various amines, and sulfides, including amino acids and glutathione have been carried out, obtaining alkylated adducts (3-16) in fairly good to quantitative yields. The reaction rate and selectivity of 1 toward nitrogen and sulfur nucleophiles, in competition with the hydration reaction, have been investigated at different pH by laser flash photolysis technique. The observed reactivity spans 7 orders of magnitude on passing from water (kNu = 5.8 M-1 s-1) to the most reactive nucleophile (2.8 × 108 M-1 s-1, 2-mercaptoethanol under alkaline conditions). These are the first direct reaction rate measurements of nucleophilic addition to the parent o-quinone methide (1). Competition experiments provided strong kinetic support to the involvement of free 1 as an intermediate in both thermal and photochemical reactions. Furthermore, several alkylation adducts regenerate 1 either by heating (9, 10, 13, and 14) or by irradiation (9, 11-13, 16). Such a thermal and photochemical reversibility of the alkylation process opens a new perspective for the use and application of such adducts as o-QM molecular carriers.
- Modica,Zanaletti,Freccero,Mella
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- THERMAL DECOMPOSITION OF 2-HYDROXYBENZYLAMINES
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The results are given of the preparation of a number of 2-hydroxybenzylamines and their thermal decomposition.The thermolysis reactions and the formation of the corresponding amines take place smoothly and with good yields.
- Vinogradova, V. I.,Yunusov, M. S.
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p. 308 - 311
(2007/10/02)
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- NOUVELLE VOIE D'ACCES AUX DIHYDRO-3,4-2H-BENZOXAZINES-1,3
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3,4-Dihydro-2H-1,3-benzoxazines were prepared from primary amines and dihalocompounds by a method which can lead to compounds dissymetrically substituted in positions 2 and 4.
- Colin, J. L.,Loubinoux, B.
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p. 4245 - 4246
(2007/10/02)
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- Syntheses d'aminoalcools-1,3 ou d'aminophenols-1,3 par reduction d'enaminones ou d'iminophenols par les hydrures metalliques. Etude structurale par infrarouge et RMN des aminoalcools-1,3 bisecondaires diastereomeres
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Enaminones, obtained by reaction of a primary amine with a β-diketone, can take three tautomeric forms: keto-enamine Ia, keto-imine Ib and imino-enol Ic.In general the keto-enamine form Ia is the most stable.Thi
- Maroni, Pierre,Cazaux, Louis,Tisnes, Pierre,Zambeti,Marianthie
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p. 179 - 186
(2007/10/02)
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