n–π Electron donor–acceptor complexes. I. Aliphatic amines with benzonitrile

1981 ◽  
Vol 59 (9) ◽  
pp. 1291-1296 ◽  
Author(s):  
J. Anunziata ◽  
J. Singh ◽  
J. J. Silber
Keyword(s):  
Experimental Data ◽  
Temperature Effect ◽  
Electron Donor ◽  
Iterative Procedure ◽  
Extinction Coefficients ◽  
A Value ◽  
Amine Structure ◽  
Donor Acceptor ◽  
Spectroscopic Behavior ◽  
Weak Electron

Interaction of diethyl, triethyl, n-butyl, di-n-butyl and tri-n-butyl amines as n-donor with benzonitrile as π-acceptor has been studied in n-hexane. The formation of weak electron donor–acceptor (EDA) complexes is proposed to explain the spectroscopic behavior of the mixtures. An iterative procedure was used to obtain values of stability constants (K) and extinction coefficients (ε). The fact that from the new absorption observed for these systems a value of K and a finite constant value of ε could be determined gives proof of the existence of EDA complexes. This conclusion is further supported by the temperature effect observed. Correlations of the experimental data with amine structure and other types of amine complexes were found.

Thiazole as a weak electron-donor unit to lower the frontier orbital energy levels of donor–acceptor alternating conjugated materials

2013 ◽  
Vol 49 (85) ◽  
pp. 9938 ◽  
Author(s):  
Elena Zaborova ◽  
Patricia Chávez ◽  
Rony Bechara ◽  
Patrick Lévêque ◽  
Thomas Heiser ◽  
...  
Keyword(s):  
Electron Donor ◽  
Energy Levels ◽  
Orbital Energy ◽  
Frontier Orbital ◽  
Conjugated Materials ◽  
Donor Acceptor ◽  
Weak Electron ◽  
Frontier Orbital Energy

The analysis of excited-state equilibria of weak electron donor–acceptor systems:

1998 ◽  
Vol 79 (2) ◽  
pp. 65-77 ◽  
Author(s):  
I. Deperasinska ◽  
J. Prochorow ◽  
J. Dresner
Keyword(s):  
Excited State ◽  
Electron Donor ◽  
Donor Acceptor ◽  
Weak Electron

n–π Electron donor–acceptor complexes. II. Aliphatic amines with dinitrobenzenes

1985 ◽  
Vol 63 (4) ◽  
pp. 903-907 ◽  
Author(s):  
Joaquín O. Singh ◽  
Jorge D. Anunziata ◽  
Juana J. Silber
Keyword(s):  
Electron Donor ◽  
Iterative Procedure ◽  
Steric Effect ◽  
Aliphatic Amines ◽  
Primary Amines ◽  
Substitution Reactions ◽  
Aromatic Nucleophilic Substitution ◽  
Donor Acceptor ◽  
Eda Complex ◽  
The Stability

The interaction of several aliphatic amines as n-donors and dinitrobenzenes (DNB) as π-acceptors has been studied in n-hexane. The formation of electron donor – acceptor (EDA) complexes is proposed to explain the spectroscopic behaviour of the mixtures. The stability constants (Ks) for these complexes have been calculated by an iterative procedure. For a given acceptor, the donor strength of RNH2 > R2NH > R3N was found. This order is explained by considering the role that steric effect may play in the EDA complex formation. On the other hand, the fact that for a given donor Ks follows the order 1,2-DNB > 1,3-DNB > 1,4-DNB, and that 1,2-DNB reacts with primary amines, led to the proposal of orientational complexes. These EDA complexes may be considered intermediates in aromatic nucleophilic substitution reactions.

scholarly journals The Determination of Molecular Quantities from Measurements on Macroscopic Systems.V. Existence and Properties of 1:1 and 2:1-Electron-Donor-Acceptor Complexes of Hexamethylbenzene with Tetracyanoethylene

1982 ◽  
Vol 37 (12) ◽  
pp. 1427-1448
Author(s):  
Wolfgang Liptay ◽  
Torsten Rehm ◽  
Detlev Wehning ◽  
Lothar Schanne ◽  
Wolfram Baumann ◽  
...  
Keyword(s):  
Experimental Data ◽  
Excited State ◽  
Electron Donor ◽  
Electric Dipole ◽  
Dipole Moments ◽  
Equilibrium Constants ◽  
Sandwich Type ◽  
Donor Acceptor ◽  
Standard Reaction ◽  
Evaluation Of Data

AbstractThe formation of electron-donor-acceptor complexes of hexamethylbenzene (HMB) with tetracyanoethylene (TCNE) was investigated by measurements of the optical absorptions, the densities, the permittivities and the electro-optical absorptions of solutions in CCl4. The careful evaluation of data based on some previously reported models, has shown that the assumption of the formation of the 1: 1 and the 2 : 1 complex agrees with all experimental data, but that the assumption of the formation of only the 1: 1 complex is contradictory to experimental facts even if the activity effects on the equilibrium constant and of the solvent dependences of observed molar quantities are taken into account. The evaluation leads to the molar optical absorption coefficients and the molar volumes of both complexes and to their electric dipole moments in the electronic ground state and the considered excited state. According to these results the complexes are of the sandwich type HMB-TCNE and HMB-TCNE-HMB. In spite of the fact that the 2: 1 complex owns a center of symmetry, at least approximately, there is a rather large electric dipole moment in its excited state. Furthermore, values for the equilibrium constants and for the standard reaction enthalpies of both complex formation reactions are estimated from experimental data.

n-π Electron donor–acceptor complexes. III. Aliphatic amines with dicyanobenzenes. Electric and steric effects of the N-substituents on complex formation

1986 ◽  
Vol 64 (8) ◽  
pp. 1491-1495 ◽  
Author(s):  
Jorge D. Anunziata ◽  
Norma S. Galaverna ◽  
Joaquín O. Singh ◽  
Juana J. Silber
Keyword(s):  
Electron Donor ◽  
Aliphatic Amines ◽  
Steric Effects ◽  
Probable Structure ◽  
Spectroscopic Behaviour ◽  
Amine Structure ◽  
Donor Acceptor ◽  
Substituent Constants ◽  
The Stability ◽  
Electronic And Steric Effects

The interaction of several aliphatic amines as n-donors with 1,2-, 1,3-, and 1,4-dicyanobenzenes as π acceptors in n-hexane has been studied. The spectroscopic behaviour of the mixtures leads us to propose that Electron Donor – Acceptor (EDA) complexes are formed. Correlations of the experimental data with the amine structure were performed for the amine–1,4-dicyanobenzene complexes. By means of free energy related substituents and regression analysis, the electronic and steric effects of three N-substituents were quantitatively separated. Thus, with K representing the stability constants of the complexes, the values of log K are correlated with Taft's polar substituent constants, σ*, and Hancock's corrected steric substituent constants, [Formula: see text] The results allowed the proposal of a probable structure of the complex, at least with respect to the donor orientation.

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