78697-71-9Relevant articles and documents
RADICAL-ANIONS OF AROMATIC COMPOUNDS. XVI. ELECTRONIC STRUCTURE OF RADICAL-ANIONS AND THE DIRECTION OF PARTIAL REDUCTION OF DISUBSTITUTED DERIVATIVES OF m-DINITROBENZENE: THE RELATIVE EFFECTS OF THE SUBSTITUENTS
Uskov, S. I.,Bilkis, I. I.,Shteingarts, V. D.
, p. 31 - 41 (2007/10/02)
It was shown by means of compounds labeled with the 15N isotope that the radical-anions of a wide range of 1,5-disubstituted 2,4-dinitrobenzenes are in most cases characterized by localization of the density of the unpaired electron at one of the nitro groups.It was concluded that the substituents can be arranged in the following order according to their ability to stabilize the form with the negatively charged nitro group at the para position: CO2- > CH3 Br > Cl N(C2H5)2 > CN > OCH3; CO2- > I.The relative effectiveness of the substituents which stabilize the form of the radical-anions with the negatively charged nitro group at the ortho position was determined theoretically as follows: OCH3 +C5H5 +H(C2H5)2.The position of the substituents in the series given above are determined by the combined effect of such factors as the effective volume, the electronic effect transmitted through the skeleton, the field effect, and the ability to form intramolecular hydrogen bonds.It was shown that the direction of partial reduction of the derivatives of m-dinitrobenzene can be predicted on the basis of data on the electronic structure of their radical-anions, which are probable key intermediates of the processes.
