TY - JOUR
T1 - Electrostatic effects on the photoreactions of nitro phenyl ethers withnucleophiles
AU - Marquet, Jordi
AU - Tomasi, Chiara
PY - 2003/12/1
Y1 - 2003/12/1
N2 - Nucleophilic aromatic photosubstitutions of 1,2-dialkoxy-4-nitrobenzenes by oxygen nucleophiles such as water or alcohols in basic media and in air equilibrated solutions, lead to low yields of substitution, following the "polar" SNAr* mechanism. Photoreduction of the nitro group is the exclusive process in an inert atmosphere. By using Topologically Controlled Coulombic Interactions (TCCI), the photosubstitution process becomes predominant, allowing the SET mechanism for SNAr* reactions to occur. This is due, on one hand, to the reduced tendency of the radical anion to be oxidized, and on the other hand, to the removal of electronic density from the nit ro group in the radial anion which lowers the rate of proton transfer from the nucleophile radical cation.
AB - Nucleophilic aromatic photosubstitutions of 1,2-dialkoxy-4-nitrobenzenes by oxygen nucleophiles such as water or alcohols in basic media and in air equilibrated solutions, lead to low yields of substitution, following the "polar" SNAr* mechanism. Photoreduction of the nitro group is the exclusive process in an inert atmosphere. By using Topologically Controlled Coulombic Interactions (TCCI), the photosubstitution process becomes predominant, allowing the SET mechanism for SNAr* reactions to occur. This is due, on one hand, to the reduced tendency of the radical anion to be oxidized, and on the other hand, to the removal of electronic density from the nit ro group in the radial anion which lowers the rate of proton transfer from the nucleophile radical cation.
KW - Electron transfer
KW - Nitroaromatics
KW - Photosubstitution
KW - Topologically controlled coulombic interactions (TCCI)
M3 - Article
SN - 1424-6376
VL - 2003
SP - 366
EP - 372
JO - Arkivoc
JF - Arkivoc
IS - 10
ER -