ChemInform Abstract: CHEMICAL BEHAVIOR OF PYRANO(2,3-C)PYRAZOL-3(2H)-ONES TOWARDS NITROGEN BASES. II. REACTION WITH ALIPHATIC AMINES

1982 ◽  
Vol 13 (4) ◽  
Author(s):  
A. MAQUESTIAU ◽  
Y. VAN HAVERBEKE ◽  
J.-J. VANDEN EYNDE
1987 ◽  
Vol 42 (2) ◽  
pp. 153-159
Author(s):  
Gerhard Raabe ◽  
Jörg Fleischhauer

The energy partitioning scheme of Morokuma et al. has been applied to the proton affinities of fourteen aliphatic amines. The electrostatic, the polarization and the charge transfer component of the proton affinities have been calculated using the MINDO/3 method. Two different sets of structural parameters have been used for the complexes of the bases and the attacking proton. Within the framework of the semiempirical method employed here, the electrostatic interaction between an attacking proton and the base was found to be positive as a result of the relative magnitudes of the repulsion terms used in the proton-electron and the proton-core interactions.In the case of the polarization term our findings roughly parallel those of Morokuma. For one of the two sets of structural parameters a good and almost group overlapping correlation was found between polarization energies and experimental proton affinities: the polarization part was found to decrease with increasing proton affinity. Independent of the choice of the amine geometries, the results for the charge transfer energy contradict the nonempirical data of Morokuma: Contrarily to his results we found values which increase in the order ammonia < methylamine < dimethylamine < trimethylamine.


2019 ◽  
Author(s):  
Yongzheng Ding ◽  
Shuai Fan ◽  
Xiaoxi Chen ◽  
yuzhen gao ◽  
Gang Li

A Pdᴵᴵ-catalyzed, ligand-enabled gamma-C(sp3)–H arylation of free primary aliphatic amines and amino esters without using an exogenous directing group is reported. This reaction is compatible with unhindered free aliphatic amines, and it is also be applicable to the rapid synthesis of biologically and synthetically valuable unnatural α-amino acids. Large scale synthesis is also feasible using this method.<br>


2020 ◽  
Vol 24 (21) ◽  
pp. 2508-2523
Author(s):  
Johana Gómez ◽  
Diego Sierra ◽  
Constanza Cárdenas ◽  
Fanny Guzmán

One area of organometallic chemistry that has attracted great interest in recent years is the syntheses, characterization and study of organometallic complexes conjugated to biomolecules with different steric and electronic properties as potential therapeutic agents against cancer and malaria, as antibiotics and as radiopharmaceuticals. This minireview focuses on the unique structural diversity that has recently been discovered in α- amino acids and the reactions of metallocene complexes with peptides having different chemical behavior and potential medical applications. Replacing α-amino acids with metallocene fragments is an effective way of selectively influencing the physicochemical, structural, electrochemical and biological properties of the peptides. Consequently, research in the field of bioorganometallic chemistry offers the opportunity to develop bioactive metal compounds as an innovative and promising approach in the search for pharmacological control of different diseases.


2005 ◽  
Vol 70 (12) ◽  
pp. 2027-2037 ◽  
Author(s):  
Teresa Łuczak

Adsorption of aliphatic amines (C1-C4) at the gold electrode was studied by tensammetry. It has been established that the experimental dependence between the gold surface coverage (Θ) and the bulk amine concentration (cA) fits satisfactorily both by the Frumkin and Flory-Huggins isotherms. The standard Gibbs energy of adsorption, ∆G°ad at Emax for Θ < 0.8 has been found to increase in the order methylamine < ethylamine < propylamine < butylamine. This is rationalised in terms of surface-adsorbate, adsorbate-adsorbate and adsorbate-solvent interactions.


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