2684-02-8Relevant articles and documents
Diazotisations in Highly Concentrated Mineral Acids: The Nitrosation Mechanism of Anilinium and Hydroxylammonium Ions through Proton Loss from the Ammonio Group
Zollinger, Heinrich
, p. 1661 - 1664 (1988)
It is shown that the acidity dependence of the rate of nitrosation of aromatic amines and of hydroxylamine in strongly acidic aqueous solutions does not necessarily involve the rearrangement of a charge transfer complex (consisting of the NO+ ion and the substrate with an NH3+ group) in concert with a proton loss at the NH3+ group.More likely, proton loss of the charge complex preceeds the ? -> N rearrangement of the NO+ ion.
Swift photoswitching in a binuclear Zn(ii) metallacycle relative to a salen-type ligand
Kumar, Amit,Pandey, Rampal,Gupta, Rakesh Kumar,Mishra, Veenu,Mobin, Shaikh M.,Pandey, Daya Shankar
, p. 6365 - 6376 (2014/04/17)
The synthesis, characterization and photoswitching behavior of a new salen type Schiff base N,N′-bis(2-hydroxy-5-phenylazobenzilidene)-2,4,6- trimethylbenzene-1,3-diamine (H2L) and a binuclear zinc(ii) metallacycle [{Zn(L)}2·2H2O] (1) have been described. Both H2L and 1 have been characterized by satisfactory elemental analyses, spectral (FT-IR, 1H, 13C NMR, ESI-MS, electronic absorption, emission) and electrochemical studies. Crystal structures of both H2L and 1 have been authenticated by single crystal X-ray diffraction analyses. These exhibit trans-cis photoisomerization upon exposure to UV light (365 nm) and get back to a more stable trans-form after withdrawal of the light. Electronic absorption, emission, 1H NMR and cyclic voltammetric studies revealed that trans-cis isomerization in metallacycle 1 is rather rapid (～5.0 s) relative to H2L (～25 s) which has been supported by theoretical studies (DFT). Relatively fast photoisomerization in 1 compared to H2L is facilitated by a small energy gap between HOMO levels of the trans- and cis-isomers. The percentage trans-cis conversion ratio for both H2L and 1 has been evaluated (55-45, H2L; 60-40%, 1) by 1H NMR studies. This journal is the Partner Organisations 2014.
Inhibition of Acid-induced decomposition of diphenyltriazenes by complexation with cyclodextrins
Xu, Tingting,Asadi, Atefeh Vaez-Zadeh,Barra, Monica
supporting information; experimental part, p. 567 - 574 (2011/04/26)
Acid-promotedN Nbond cleavage in 1,3-diphenyltriazenes (X-Ph-N=N-NH-Ph-X X = H, 4-OCH3), leading to formation of diazonium ions and anilines, is strongly inhibited in aqueous solutions in the presence of cyclodextrins (CDs). The inhibition is ascribed to the formation of inclusion complexes that render the guest diphenyltriazene significantly less basic as a result of the less polar nature of the CD cavity (amicrosolvent effect). Association equilibrium constants for 1:1 host-guest complexes increase in the order α-CD 3 being larger than those for X = H. In the case of α-CD, formation of 2:1 host-guest complexes is also involved.
