Ueber Tetramidobenzol und seine Derivate

Abstract

Silbe Dioder Trivor denjenigen Kohlenwasseretofiest zu setzen sein, welcher in der mehrfachen Zahl vorkommt. Der Kiirper Ce (N2 C, H& hiesse alsdann Pheno-oder Benzo-Tritolazin , der Korper (H 0 ) 2 0 2 c6Na c~ H6 Dioxychinontolazin , der Kiirper 0 4 Cs Nz C7 H6 Dichinoyltolazhi, oder richtiger Dichinoylbenzotolazin.

Extendable nickel complex tapes that reach NIR absorptions

“…16 The metallation of 2 with a ruthenium precursor did not afford the corresponding (and expected) dinuclear complex but instead an oxidized species 3 in which the carbonyl functions impede the communication between the two metal centers. This shortcoming can be explained by the strongly limited access to 2 owing to its in situ preparation in solution, 16,17 or deposit by sublimation on a CsI plate cooled by closed-cycle refrigeration at 15 K. 18 In contrast, N-substituted analogues of type 4 (R = alkyl or aryl) have attracted much more interest as their easy access paved the way to their use as ligand for the preparation of dinuclear complexes 5 with a high degree of electronic delocalization. [19][20][21] Importantly, no metal complex oligomers based on 4 could be attained presumably due to the steric hindrance of the N-substituents.…”

“…Spectro-photophysical and theoretical studies revealed electronic absorption bands in specific regions from UV to NIR depending on the size of the oligomers. The synthesis of 2 was based on the venerable Nietzki's work (1887) 17 who mentioned in water spontaneous oxidation in air of the electron-rich tetraaminobenzene 6 yielding the 2,5-diamino-1,4-benzoquinonediimine 2 (Scheme 1). When the same reaction was carried out in methanol, 2 was directly precipitated as a brown solid in 79% yield, preventing its reaction with 6 and/or other oxidized species.…”

Syntheses, Structures and Basicities of 1,2,4,5-Tetrakis(dimethylamino)benzene and 2,3,6,7-Tetrakis(dimethylamino)naphthalene

“…Although the precursor 1,2,4,5-tetraaminobenzene had been prepared already decades ago, [6] the tetrakis(dimethylamino) compound 4 to our knowledge had not been reported in literature. An improved synthesis of the tetraaminobenzene started from 1,3-dichlorobenzene which was nitrated preferentially in the 4,6-positions.…”

A purple odyssey: synthesis and structure of 3-amino-4-hydroxy-6-oxocyclohexa-2,4-dien-1-iminium chloride monohydrate

“…In the course of our ongoing studies (Plater & Harrison, 2013, 2014aPlater & Jackson, 2014) on new conjugated products obtained from the oxidation of aromatic amines, we attempted the oxidation of 1,2,4,5-tetraaminobenzene, 1. As long ago as 1887, it was demonstrated (Nietzki & Hagenbach, 1887) that this compound undergoes aerial oxidation to form 2,5-diamino-1,4-benzoquinonediimine, 2. More recently, Braunstein et al (2003) have studied the oxidation of compound 1 and the related compound 2,4-diaminoresorcinol, 3, to synthesize (1E)-N-(2,2-dimethylpropyl)-5-[(2,2-dimethylpropyl)amino]-2-hydroxy-4-oxocyclohexa-2,5-dien-1-iminium chloride, 4, which generates the zwitterion 5 when treated with base.…”