n—π electron-donor—acceptor complexes—IV. The interaction of aliphatic amines with 1,3-dicyanobenzene in n-hexane. The importance of preferred orientation in the stability of the complexes

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.

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

Canadian Journal of Chemistry ◽

10.1139/v86-245 ◽

1986 ◽

Vol 64 (8) ◽

pp. 1491-1495 ◽

Cited By ~ 6

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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Electrochemical study of the stability of the electron-donor—acceptor (EDA) complex between N,N,N′,N′-tetramethyl-p-phenylendiamine and m-dinitrobenzene in acetonitrile

Electrochimica Acta ◽

10.1016/0013-4686(87)87011-1 ◽

1987 ◽

Vol 32 (1) ◽

pp. 71-77 ◽

Cited By ~ 19

Author(s):

M.A. Zon ◽

H. Fernández ◽

L. Sereno ◽

J.J. Silber

Keyword(s):

Electron Donor ◽

Electrochemical Study ◽

Donor Acceptor ◽

Eda Complex ◽

The Stability

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Interaction between tetracyanoethylene and naphthalene in reverse micelles of AOT in n-hexane. The electron-donor properties of AOT

Canadian Journal of Chemistry ◽

10.1139/v96-177 ◽

1996 ◽

Vol 74 (9) ◽

pp. 1603-1608 ◽

Cited By ~ 3

Author(s):

M. A. Biasutti ◽

Juana J. Silber

Keyword(s):

Electron Donor ◽

Reverse Micelles ◽

Formation Constants ◽

Local Concentration ◽

Micellar Media ◽

Visible Spectroscopy ◽

Donor Acceptor ◽

Uv Visible ◽

The Stability ◽

Homogeneous Media

The electron donor–acceptor (EDA) interaction between TCNE and naphthalene (Naph) in n-hexane and reverse micelles of AOT in n-hexane was studied by UV–visible spectroscopy with the aim of determining the influence of the micellar media on the EDA interaction. The spectra of the mixtures of TCNE–Naph in n-hexane show two typical maxima at 418 and 534 nm, assigned to the formation of a π–π EDA complex. In the micellar media a new band is observed at 398 nm. When the spectra of TCNE in n-hexane are studied in the presence of AOT two new bands at 398 and 418 nm are detected. These bands are consistent with an EDA interaction between TCNE and AOT as n-donor. The stability constants of this interaction were calculated for AOT concentrations below the CMC and in the micellar media at different W(W = [H2O]/[AOT]). The results give evidence of the tendency of AOT to interact very strongly with electron acceptors. Moreover, in the system TCNE–Naph in the micellar media it is shown that Naph and AOT compete to form a complex with TCNE. The formation constants of the complexes of AOT–Naph in the micelle system were determined at W = 0 and 5. Despite the competition of AOT for TCNE the stability constant for the complex TCNE–Naph is higher than in homogeneous media, probably due to the high local concentration of the acceptor in the micelle. Key words: reverse micelles, aerosol-OT, tetracyanoethylene, naphthalene, electron donor–acceptor complexes.

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Deaminative Borylation of Aliphatic Amines Enabled by Visible Light Excitation of an Electron Donor-Acceptor Complex

Chemistry - A European Journal ◽

10.1002/chem.201804246 ◽

2018 ◽

Vol 24 (65) ◽

pp. 17210-17214 ◽

Cited By ~ 91

Author(s):

Frederik Sandfort ◽

Felix Strieth-Kalthoff ◽

Felix J. R. Klauck ◽

Michael J. James ◽

Frank Glorius

Keyword(s):

Visible Light ◽

Electron Donor ◽

Aliphatic Amines ◽

Acceptor Complex ◽

Donor Acceptor ◽

Light Excitation

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Metal-Free Photoinduced Hydroalkylation Cascade Enabled by an Electron-Donor-Acceptor Complex

10.26434/chemrxiv.11912073 ◽

2020 ◽

Author(s):

José Tiago Menezes Correia ◽

Gustavo Piva da Silva ◽

Camila Menezes Kisukuri ◽

Elias André ◽

Bruno Pires ◽

...

Keyword(s):

Electron Donor ◽

Functional Group ◽

Photoexcited Electron ◽

One Pot ◽

Quaternary Centers ◽

Metal Free ◽

Acceptor Complex ◽

Catalyst Free ◽

Donor Acceptor ◽

Radical Cascade

A metal- and catalyst-free photoinduced radical cascade hydroalkylation of 1,7-enynes has been disclosed. The process is triggered by a SET event involving a photoexcited electron-donor-aceptor complex between NHPI ester and Hantzsch ester, which decomposes to afford a tertiary radical that is readily trapped by the enyne. <a>The method provides an operationally simple, robust and step-economical approach to the construction of diversely functionalized dihydroquinolinones bearing quaternary-centers. A sequential one-pot hydroalkylation-isomerization approach is also allowed giving access to a family of quinolinones. A wide substrate scope and high functional group tolerance was observed in both approaches</a>.

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