Biomass base membrane with phenol hydroxy-amino group for ultraselective adsorption of radioactive Co(II) in trace concentration

The OH radical rapidly reacts with CH3NH2 and C6H5NH2 but reacts slower with CH3NH3⊕, respectively C6H5NH3⊕. In the reaction with methylamine. the complex is formed which loses water with τ½=26 µs. The addition of OH to the aromatic ring of aniline occurs in 20% of the reactions. The hydroxy-amino-cyclohexadienyl radical has its absorption maximum at 3500 A. It decays by elimination of water to yield the anilino radical C6H5NH (τ½= 5.7µs at pH = 7), H⊕ and OH⊖ ions catalyse the decay. In 80% of the reactions. · OH adds to the amino group of aniline. The subsequent loss of water or of OH⊖ occurs rapidly (<1 µs). However, the basic form of the addition complex decays much more slowly (τ½=10 µs at pH= 13.7). The pK-value of the equilibriumis estimated to be equal to 11 — 12. The absorption spectra of C6H5NH2® and the pK-value of 7.0 of C6H5NH2⊕ first described by LAND and PORTER are confirmed.

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Synthesis and properties of some gelatin derivatives with substituents at the amino group

Journal of Biochemical Toxicology ◽

10.1002/jbt.2570151008 ◽

1965 ◽

Vol 15 (10) ◽

pp. 479-488

Author(s):

R. C. Clark ◽

W. G. Cobbett ◽

J. A. Gibbs ◽

R. T. Jones ◽

A. A. Leach ◽

...

Keyword(s):

Amino Group

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Aminocoumarins: A Privileged Precursor for the Synthesis of Fused Heterocycles

Current Organic Chemistry ◽

10.2174/1385272823666190514073610 ◽

2019 ◽

Vol 23 (9) ◽

pp. 1045-1075 ◽

Cited By ~ 1

Author(s):

Saigal ◽

Sumbulunnisan Shareef ◽

Habibur Rahman ◽

Md. Musawwer Khan

Keyword(s):

Chemical Reactivity ◽

Structural Systems ◽

Natural Occurrence ◽

Amino Group ◽

Active Compounds ◽

The Past ◽

Fused Heterocycles

Aminocoumarins are one of the important core structural systems, present in several biologically and medicinally active compounds. Owing to its natural occurrence, potential pharmacological applications and remarkable versatility as a privileged precursor, several proficient synthetic protocols have been reported in the literature over the past years. The presence of an amino group and enamine carbon enhances its chemical reactivity and thus such functionality is repeatedly used for the construction of various fused and simple heterocycles. This review highlights the preparation of different aminocoumarins and their applications for the construction of a variety of five, six and eight membered fused heterocycles.

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Simple theoretical models for elimination reactions on polar catalysts; The reactivity of halogeno-, hydroxy-, amino- and mercaptopropane

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19822180 ◽

1982 ◽

Vol 47 (8) ◽

pp. 2180-2189 ◽

Cited By ~ 2

Author(s):

Jiří Sedláček

Keyword(s):

Theoretical Models ◽

Molecular Orbitals ◽

Localized Molecular Orbitals ◽

Hydroxy Amino ◽

Elimination Reactions ◽

Simple Models

CNDO/2 calculations have been made for simple models of the adsorption of (CH3)2CHZ molecules (Z = Cl, OH, NH2, and SH) on the surface of polar catalysts. The results of these calculations and their interpretation by the method of configuration analysis in terms of uniformly localized molecular orbitals made it possible to explain satisfactorily a series of experimental facts. The mechanism and stereoselectivity of the reaction as well as reactivity trends for the series of the molecules studied are discussed.

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Laser optoacoustic detection of trace concentration levels of ethylene, vinylchloride, and styrene in the atmosphere

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19892667 ◽

1989 ◽

Vol 54 (10) ◽

pp. 2667-2673 ◽

Cited By ~ 5

Author(s):

Vojtěch Steiner ◽

Pavel Engst ◽

Zdeněk Zelinger ◽

Milan Horák

Keyword(s):

Detection Limit ◽

Emission Line ◽

Laser Line ◽

Laser Source ◽

Trace Concentration ◽

Selective Determination ◽

Hygienic Standard ◽

Trace Concentrations ◽

Concentration Levels

The optoacoustic analyzer with a tunable CO2 laser source employed in the present work permits a selective determination of ethylene in trace concentrations higher than 5 ppb (=detection limit for the 10P(14) emission line of the CO2 laser, ν = 949.5 cm-1) and of vinylchloride higher than 42 ppb (= detection limit for the 10P(22) CO2 laser line, ν= 942.4 cm-1). this method covers for both compounds the concentration range corresponding to the hygienic standard. It can be also used for the determination of styrene vapour with concentrations higher than 1.5 ppm.

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Substituent Effects on the Basicity of ortho-, meta- and para-substituted N1,N1-Dimethyl-N2-phenylformamidines in Ethanol and in Water

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19920113 ◽

1992 ◽

Vol 57 (1) ◽

pp. 113-118

Author(s):

Ewa Daniela Raczyńska

Keyword(s):

Quantitative Analysis ◽

Aqueous Ethanol ◽

Substituent Effects ◽

Amino Group

The relative δpKa values of ortho-, meta-, and para-substituted N1,N1-dimethyl-N2-phenylformamidines obtained in 95.6% aqueous ethanol have been compared with those in water. The comparison shows only some differences in the ortho substituent effects. The meta and para substituent effects in ethanol are not very different from those in water. Quantitative analysis of the experimental δpKa values based on the Taft equation has led to separation of the total electromeric effects into the inductive and mesomeric effects. As compared to the amino group in anilines, the formamidine group is more sensitive to the transmission of the inductive than the mesomeric effects.

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Semisynthesis of peptides - New strategy for specific protection and deprotection of the α-amino group of recombinantly-produced peptide fragments

Collection Symposium Series ◽

10.1135/css199901165 ◽

1999 ◽

Author(s):

Johann M. Brass ◽

Julie Frank ◽

Fred W. Wagner ◽

Hans Stocker ◽

Erich Wünsch

Keyword(s):

Amino Group ◽

Peptide Fragments ◽

New Strategy

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Induced Smectic Phases II. Influence of the Amino Substituent on the Induction of Smectic Phases

Zeitschrift für Naturforschung A ◽

10.1515/zna-1981-1011 ◽

1981 ◽

Vol 36 (10) ◽

pp. 1086-1091 ◽

Cited By ~ 1

Author(s):

F. Schneider ◽

N. K. Sharma

Keyword(s):

Liquid Crystal ◽

Electron Donor ◽

Amino Group ◽

Donor Property ◽

Smectic Phases ◽

Ct Complexes ◽

Induced Smectic Phases

The diagrams of state have been studied for some liquid crystal mixtures which show the induction of smectic phases. Each of the systems studied contains one component with an amino group which influences the polarity and the electron donor property of the molecules. The discussion of the diagrams of state, of the thickness of the smectic layers and of the colours of the mixtures, which indicate the formation of CT complexes, shows that existing models can not explain the induction of smectic phases.

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