THE STRUCTURE OF PYRROLE SALTS AND THE BASIC STRENGTHS OF SOME SIMPLE PYRROLES

1958 ◽  
Vol 36 (12) ◽  
pp. 1686-1690 ◽  
Author(s):  
E. Bullock
Keyword(s):  
Secondary Amine ◽  
Infrared Spectra ◽  
Spectroscopic Data ◽  
Free Base ◽  
Substituted Pyrroles ◽  
Amine Salts

The infrared spectra of hydrohalide salts of some substituted pyrroles are typical of secondary amine salts. Unlike the free base, cryptopyrrole hydrochloride is easily hydrogenated. The basic strengths of cryptopyrrole and 2,4-dimethylpyrrole are calculated from ultraviolet spectroscopic data.

THE INFRARED SPECTRA OF SECONDARY AMINES AND THEIR SALTS

1956 ◽  
Vol 34 (12) ◽  
pp. 1782-1795 ◽  
Author(s):  
R. A. Heacock ◽  
Léo Marion
Keyword(s):  
Amino Acids ◽  
Secondary Amine ◽  
Infrared Spectra ◽  
Secondary Amines ◽  
Amino Group ◽  
Absorption Bands ◽  
Secondary Amino ◽  
Amine Salts

The infrared spectra of a number of secondary bases and of their salts have been examined. The spectra of the salts differ from those of the corresponding bases in containing several absorption bands that are absent from the latter. Those of the new bands occurring in the region 1620 to 1560 cm.−1, which are due to NH2+ deformation vibrations, are characteristic of secondary amine salts, and can be used to detect the presence of a secondary amino group in the original molecule. With aromatic bases the spectra are complicated because the ring absorption occurs in the same region, but in many cases the assignment can still be made, although with less certainty. In zwitterionic substances such as the secondary aliphatic amino acids, the function is more difficult to detect.

Synthesis of N4-Substituted Derivatives of 1-[2-(Phosphonomethoxy)ethyl]cytosine and Its Diisopropyl Ester as a Model Reaction for the Synthesis of N4-Substituted Derivatives of Cidofovir

2005 ◽  
Vol 70 (12) ◽  
pp. 2066-2074 ◽  
Author(s):  
Šárka Chalupová ◽  
Antonín Holý ◽  
Milena Masojídková
Keyword(s):  
Secondary Amine ◽  
Model Reaction ◽  
Aqueous Methanol ◽  
Derivatives Of ◽  
Amine Salts

We have studied the reaction of 1-[2-(phosphonomethoxy)ethyl]cytosine (1) and its diisopropyl ester (2) with triethylammonium hydrogensulfite in 60% aqueous methanol. In the presence of some primary or secondary amine salts, at 25-70 °C, this reaction affords transaminated derivatives 4a-4e and 5a, 5b as main products accompanied by uracil compounds. However, with certain amines the reaction failed.

Infrared spectra of the interactions of aniline and porous glass surfaces

1969 ◽  
Vol 47 (8) ◽  
pp. 1281-1287 ◽  
Author(s):  
M. J. D. Low ◽  
V. V. Subba Rao
Keyword(s):  
Nitrogen Atom ◽  
Aromatic Ring ◽  
Secondary Amine ◽  
Infrared Spectra ◽  
Porous Glass ◽  
Weak Interactions ◽  
Amine Group ◽  
Oh Groups ◽  
Glass Surfaces ◽  
Adsorption And Dissociation

Infrared spectra were recorded of aniline sorbed on highly dehydroxylated, deuterated, and on fluoridated porous glass as well as on pure and boria-impregnated silica. The results suggest that two types of weak interactions involving the surface SiOH and B—OH groups occurred; the nitrogen atom of the amine was hydrogen bonded to surface OH and there was an interaction between OH groups and the π system of the aromatic ring. Some aniline chemisorbed on surface boron via the nitrogen atom of the amine group. Some aniline chemisorbed dissociatively to form secondary amine structures bonded through the nitrogen to surface boron atoms and new B—OH groups formed. Surface boron impurity acted as an adsorption and dissociation center.

Anomalous infrared spectra of codeine free base in potassium bromide pellet

1985 ◽  
Vol 173 ◽  
pp. 373-375
Author(s):  
Hiromitsu Kanai ◽  
Veronica Inouye ◽  
Reginald Goo
Keyword(s):  
Infrared Spectra ◽  
Potassium Bromide ◽  
Free Base

scholarly journals Search and characterization of T-type planetary mass candidates in the σ Orionis cluster

2010 ◽  
Vol 6 (S276) ◽  
pp. 489-490
Author(s):  
Karla Peña Ramírez ◽  
Maria R. Zapatero Osorio ◽  
Victor J.S. Béjar
Keyword(s):  
Infrared Spectra ◽  
Spectral Type ◽  
Spectroscopic Data ◽  
Near Infrared ◽  
Cluster Membership ◽  
Planetary Mass ◽  
Near Infrared Spectra ◽  
Motion Measurements ◽  
Astrometric Data

AbstractWe present new photometric and astrometric data available for S Ori 70 and 73, the two T-type planetary-mass member candidates in the σ Orionis cluster (~3 ± 2 Myr, d~360 pc). S Ori 70 (J ~ 19.9 mag) has a spectral type of T5.5 ± 1.0 measured from published near-infrared spectra, while no spectroscopic data are available for S Ori 73 (J ~ 21 mag). We estimate the spectral type of S Ori 73 by using J, H, and CH4off (λc=1.575 μm, Δλ=0.112 μm) photometry and comparing the H-CH4off index of S Ori 73 with the colors of field stars and brown dwarfs of spectral types in the range F to late T. The locations of S Ori 70 and 73 in the J-H vs H-CH4off color-color diagram are consistent with spectral types T8 ± 1 and T4 ± 1, respectively. Proper motion measurements of the two sources are larger than the motion of the central σ Ori star, making their cluster membership somehow uncertain.

The infrared spectra of theobromine salts

1967 ◽  
Vol 45 (23) ◽  
pp. 2899-2902 ◽  
Author(s):  
Denys Cook ◽  
Zephyr R. Regnier
Keyword(s):  
Hydrogen Bond ◽  
Nitrogen Atom ◽  
Infrared Spectra ◽  
Imidazole Ring ◽  
Free Base ◽  
Absorption Bands ◽  
Out Of Plane ◽  
Stretching Vibrations ◽  
Deformation Modes ◽  
Infrared Absorption Bands

From the infrared spectra of theobromine salts it is concluded that the salts are probably arranged in hydrogen-bonded centrosymmetric pairs involving [Formula: see text] interactions. [Formula: see text] anion− hydrogen bonds are formed by protonation of the free nitrogen atom (N9) in the imidazole ring. Infrared absorption bands arising from the former hydrogen bond constantly appear near 3 000 cm−1, whereas those from the latter shift from 2 580 to 3 300 cm−1, depending on the anion. In-plane NH and N+H deformation modes give bands near 1 485 and 1 160 cm−1, respectively. Out-of-plane NH modes have been located, but precise assignments are not possible.The assignments for some other bands which show deuteration shifts are detailed, and the carbonyl stretching vibrations which increase in frequency on protonation of the free base are identified.

Secondary Amine Salts of Some Thiophenols

1950 ◽  
Vol 72 (9) ◽  
pp. 4281-4281 ◽  
Author(s):  
Gerald F. Grillot ◽  
Thomas J. Brooks
Keyword(s):  
Secondary Amine ◽  
Amine Salts

Pyrrole studies. IX. The infrared spectra of 1-substituted pyrroles

1966 ◽  
Vol 19 (2) ◽  
pp. 289 ◽  
Author(s):  
RA Jones
Keyword(s):  
Infrared Spectra ◽  
Infrared Absorption ◽  
Absorption Bands ◽  
Substituted Pyrroles ◽  
Infrared Absorption Bands

The positions and intensities of the characteristic infrared absorption bands of the pyrrole nucleus in the region 2000-600 cm-1 of 45 1-substituted pyrroles, 2,5-dimethylpyrroles, and 3,4-dimethylpyrroles are recorded and discussed.

scholarly journals On-Demand Release of Secondary Amine Bases for the Activation of Catalysts and Crosslinkers

2021 ◽  
Author(s):  
Benjamin Spitzbarth ◽  
Rienk Eelkema
Keyword(s):  
Nmr Spectroscopy ◽  
Secondary Amine ◽  
Self Healing ◽  
Polymer Gel ◽  
Free Base ◽  
H Nmr ◽  
On Demand ◽  
Water Shift ◽  
Reaction Cascades

We demonstrate that the species present in the equilibrium of DCv ureas can be employed in reaction cascades and as triggered organocatalysts. Easily controllable stimuli like heat or addition of water shift the equilibrium towards isocyanate and free base which can function as an in situ released reagent, both catalytically and in an equimolar fashion in different reactions. While applying heat to the system leads to a reversible liberation of amine base, addition of water makes this release irreversible. We demonstrate this application of DCv ureas with two examples via <sup>1</sup>H-NMR spectroscopy. Firstly, we use the liberated base to activate a protected organocatalyst for acylhydrazone formation. Secondly, this base can be employed to trigger the release of nitrile-N-oxides from chlorooximes, which can react with 4-arm PEG-thiols to form a thiohydroximate polymer gel. These findings show the utility of DCv hindered ureas beyond their application in self-healing.

Sign in / Sign up

Export Citation Format

Share Document