- Reactions of 2,2-diphenyl-1-picrylhydrazyl (DPPH) with two syringylic phenols or one aroxide derivative
-
The reactions between excess 2,2-diphenyl-1-picrylhydrazyl (DPPH) and either 4-hydroxy-3,5-dimethoxybenzaldehyde (syringaldehyde, 1) or methyl 4-hydroxy-3,5-dimethoxyben-zoate (methyl syringate, 2) afford different products from those obtained with the corresponding aroxide (3)of l.In the former case (with the free phenols) the aryloxy (syringyl) group substitutes the 4-nitro group of DPPH, yielding dinitro products 7 and 8 (new stable free radicals) and 9 and 10 (corresponding hydrazines), whereas in the latter case (with the sodium aroxide 3) the aryloxy (syringyl) group substitutes one of the phenyl groups of DPPH in the para position, forming trinitro products 14 (new stable free radical) and 15 (corresponding hydrazine). Accompanying products were isolated by TLC and identified by their 1H NMR, 13C NMR, UV/Vis, and EPR spectra. The reaction mechanisms involving hy-drazyl and aroxyl free radicals are discussed.
- Hristea, Elena N.,Covaci-C?mpeanu, Irina C.,Ioni?ǎ, Gabriela,Ioni?ǎ, Petre,Draghici, Constantin,Cǎproiu, Miron T.,Hillebrand, Mihaela,Constantinescu, Titus,Balaban, Alexandru T.
-
experimental part
p. 626 - 634
(2009/07/17)
-
- A study of Br/NO2 substitution reactions and nuclear magnetic resonance of 2,2-diaryl-1-picrylhydrazines
-
A series of compounds of type 2-Ma-2-Mb-1-picrylhydrazine with Ma, Mb = phenyl, p-bromophenyl, and p-nitrophenyl has been investigated.Conversion of p-bromophenyl into p-nitrophenyl caused by reaction with NO2 h
- Currie, Patricia F.,Quail, J. Wilson,Rusk, Ann C.M.,Weil, John A.
-
p. 1760 - 1765
(2007/10/02)
-