The Alkali Salts of 2,2-Diphenyl-1-picrylhydrazine¹

Abstract

Hoboken, N. J.

The crystal structure of potassium 1-(N,N-diphenylhydrazono)-2,4,6-trinitrobenzenide

“…As a result, the two ortho nitro groups are rotated through large angles to avoid close contacts between nitro oxygen atoms and N(4). In particular, the nitro groups analogous to O(1)-N(1)-O (2) in the ion are rotated 60.6 and 57. l o from coplanarity with the trinitrobenzenide ring in the two independent molecules of the free radical. The boat conformation in the ion obviates the need for much of this rotation.…”

“…Isolation and characterization of salts produced by the reaction was reported by Weil and Janusonis (2) in 1962. Their nmr results indicated that the 1-(N,Ndipheny1hydrazono)-2,4,6-trinitrobenzenide ion was indeed formed.…”

“…Their nmr results indicated that the 1-(N,Ndipheny1hydrazono)-2,4,6-trinitrobenzenide ion was indeed formed. Optical spectroscopic studies showed that the primary peak responsible for the intense colour occurs at 424 nm and is independent of the cationic species present (2). The transitions giving rise to the colour were therefore assumed to be internal to the anion, probably involving quinoid and nitronic canonical structures.…”

Reaction of 2,2-Diphenyl-1-picrylhydrazyl with HO•, O2•–, HO– ,and HOO– Radicals and Anions

“…Preliminary investigation revealed that the intensity of the characteristic absorption band of DPPH (1a) at λ max = 520 nm decreases due both to the formation of the anion (3a) with λ max = 428 nm [8,38] via a redox process involving the superoxide radical-anion (eqs. 4 and 5), and to other reactions.…”

Scavenging the hydroxyl radical by 2,2-diphenyl-1-picrylhydrazyl

“…The main constituents of the reaction mixture after 90 minutes were: 2,2-diphenyl-1-picrylhydrazine (2, 45% yield), 2-(4-hydroxyphenyl)-2-phenyl-1-picrylhydrazine (3, 12% yield), and 2-(4-nitrophenyl)-2-phenyl-1-picrylhydrazine (5, 18% yield). In Figure 1 one can observe how the visible absorption spectrum changed during the reaction: the DPPH peaks with λ max 328 and 520 nm decreased, and new bands appeared due to the formation of reaction products 2 (316 nm), 17 We checked that UV irradiation of 8a or 8b in benzene generates HO…”