2-Aminodiphenylamine

A colorimetric sensor for Cu2+ in aqueous solution based on metal ion-induced deprotonation: deprotonation/protonation mediated by Cu2+-ligand interactions.[Pubmed:19240909]

Dalton Trans. 2009 Mar 14;(10):1761-6.

A Cu2+-specific colorimetric sensor of a 1,8-naphthalimide chromophore integrated with a 2-Aminodiphenylamine (2-adpa)-based receptor was designed and synthesized. Sensor had high selectivity and sensitivity for Cu2+ in neutral aqueous buffer solution. The analytical detection limit (ADL) was 3.0 x 10(-7) M. Based on the Cu2+-induced deprotonation of the diarylamino "NH" moiety, the coordination mode was proposed with 1:1 stoichiometry between and Cu2+. These results opened up possibilities for the construction of novel colorimetric sensors with a red-shift absorption in a D-pi-A system.

Chemical oxidative polymerization of aminodiphenylamines.[Pubmed:18489148]

J Phys Chem B. 2008 Jun 12;112(23):6976-87.

The course of oxidation of 4-aminodiphenylamine with ammonium peroxydisulfate in an acidic aqueous ethanol solution as well as the properties of the oxidation products were compared with those of 2-Aminodiphenylamine. Semiconducting oligomers of 4-aminodiphenylamine and nonconducting oligomers of 2-Aminodiphenylamine of weight-average molecular weights 3700 and 1900, respectively, were prepared by using an oxidant to monomer molar ratio of 1.25. When this ratio was changed from 0.5 to 2.5, the highest conductivity of oxidation products of 4-aminodiphenylamine, 2.5 x 10 (-4) S cm (-1), was reached at the molar ratio [oxidant]/[monomer] = 1.5. The mechanism of the oxidative polymerization of aminodiphenylamines has been theoretically studied by the AM1 and MNDO-PM3 semiempirical quantum chemical methods combined with the MM2 molecular mechanics force-field method and conductor-like screening model of solvation. Molecular orbital calculations revealed the prevalence of N prim-C10 coupling reaction of 4-aminodiphenylamine, while N prim-C5 is the main coupling mode between 2-Aminodiphenylamine units. FTIR and Raman spectroscopic studies confirm the prevalent formation of linear N prim-C10 coupled oligomers of 4-aminodiphenylamine and suggest branching and formation of phenazine structural units in the oligomers of 2-Aminodiphenylamine. The results are discussed with respect to the oxidation of aniline with ammonium peroxydisulfate, leading to polyaniline, in which 4-aminodiphenylamine is the major dimer and 2-Aminodiphenylamine is the most important dimeric intermediate byproduct.

Spectral characteristics of 2-aminodiphenylamine in different solvents and at various pH values.[Pubmed:11446691]

Spectrochim Acta A Mol Biomol Spectrosc. 2001 Jun;57(7):1361-7.

The absorption and fluorescence spectra of 2-Aminodiphenylamine (2ADA) have been studied as a function of solvent polarity and acid concentration. Analysis of solvatochromic and prototropic shifts of 2ADA reveals: (i) the presence of intramolecular hydrogen bonding between imino and amino groups in the ground state, (ii) dual fluorescence (360 and 430 nm) of the monocation (2ADA+) formed by the protonation of amino group; and (iii) proton-induced quenching of the monocation (2ADA+) fluorescence. In the dual fluorescence of 2ADA+, the longer wavelength emission at 430 nm is found to be from the twisted form of the monocation. The rate constants of the proton-induced quenching of 2ADA+ are determined.

Cometabolic transformation and cleavage of nitrodiphenylamines by three newly isolated sulfate-reducing bacterial strains.[Pubmed:16535317]

Appl Environ Microbiol. 1996 May;62(5):1710-6.

Three sulfate-reducing bacterial strains (Desulfovibrio sp. strain SHV, Desulfococcus sp. strain WHC, and Desulfomicrobium sp. strain WHB) with the capacity to cometabolize 2-nitrodiphenylamine, 4-nitrodiphenylamine, and 2,4-dinitrodiphenylamine were newly isolated. Before breaking down the diphenylamine structure, these strains cometabolically reduce the nitrodiphenylamines to the corresponding aminodiphenylamines during anaerobic oxidation of the growth substrate lactate (Desulfovibrio strain SHV and Desulfomicrobium strain WHC) or benzoate (Desulfococcus strain WHB), leading to the formation of aniline and a smaller quantity of methylaniline. These compounds were not further metabolized by the sulfate reducers. The anaerobic metabolism of aminodiphenylamines also led to the formation of heterocyclic condensation products such as phenazine and acridine derivatives, provided that they contained an amino group in the ortho position of the diphenylamine (e.g., 2-Aminodiphenylamine or 2,4-diaminodiphenylamine). In addition, low levels of indole and benzothiazole derivatives were identified, but these also were not further metabolized by the three sulfate-reducing strains.

Reduction of Nitrated Diphenylamine Derivatives under Anaerobic Conditions.[Pubmed:16535118]

Appl Environ Microbiol. 1995 Sep;61(9):3282-7.

2-Nitrodiphenylamine, 4-nitrodiphenylamine, and 2,4-dinitrodiphenylamine were anaerobically metabolized in sediment-water batch enrichments inoculated with mud from the German North Sea coast. The first intermediate in 2,4-dinitrodiphenylamine degradation was 2-amino-4-nitrodiphenylamine, which appeared in large (nearly stoichiometric) amounts before being completely reduced to 2,4-diaminodiphenylamine. Of the second theoretically expected metabolite, 4-amino-2-nitrodiphenylamine, only traces were detected by gas chromatographic-mass spectrometric analysis in highly concentrated extracts. In addition, low levels of 4-nitrodiphenylamine, which may be the product of ortho deamination of intermediately produced 2-amino-4-nitrodiphenylamine, were observed. 2-Nitrodiphenylamine and 4-nitrodiphenylamine were primarily reduced to 2-Aminodiphenylamine and 4-aminodiphenylamine, respectively. Diphenylamine was never detected in any experiment as a theoretically possible intermediate. Results from studies with dense cell suspensions of anaerobic, aromatic-compound-mineralizing bacteria confirmed the transformation reactions, which were carried out by microorganisms indigenous to the anaerobic coastal water sediment.