Electronic properties and ultraviolet absorption and fluorescence spectra of 2-pyridinamine

Spectral characteristics of 2-(4′-amino-3-pyridyl)benzimidazole: Effects of solvent and acid or base concentration

“…(i) 2-aminopyridine (2-APy) [7][8][9][10][11] exists as amine in both S 0 and S 1 states. As said earlier, -NH 2 group becomes stronger acid and pyridine QN-becomes stronger base on excitation to S 1 state.…”

Solvatochromism and prototropism in 6-aminonicotinic acid

“…Although the results of Table 1 for S 1 state, obtained by fully optimizing the geometry of each species in S 1 state and taking into consideration the configuration interactions (CI ¼ 5 in MOPAC, 100 configurations), suggest that 6-ANA-IZ is thermodynamically more favourable than 6-ANA-A (21.6 kJ mol À1 under isolated conditions and 34.9 kJ mol À1 when dipolar solvation energy in water is included), an activation barrier for IPT in S 1 state is still very large (301 kJ mol À1 ). Similar to 2-AP [52], it may be concluded that 6-ANA is present in amino form both in S 0 and S 1 states. Heats of formation and DFT calculations in S 0 state and under isolated conditions (Table 1) support the above conclusions.…”

“…On comparing the amino-imine equilibrium in 2-AP [52,53] and based on AM1 data (Table 1), it is also found that amine form of 6-ANA is the most stable as compared to 6-ANA-IE and 6-ANA-IZ by 63.7 and 146 kJ mol À1 under isolated conditions and 59 and 132.8 kJ mol À1 when dipolar solvation energies are included in S 0 state. Activation energy found for proton transfer from 6-ANA to 6-ANA-IE in S 0 state is 396 kJ mol À1 .…”

Tetrakis(2-amino-6-methylpyridinium) hexachloridobismuthate(III) chloride monohydrate

“…For related structures, see: Albrecht et al (2003); Feng et al (2007); Inuzuka & Fujimoto (1986, 1990; Ishikawa et al (2002); Jin et al (2000Jin et al ( , 2001Jin et al ( , 2005; Luque et al (1997); Nahringbauer & Kvick (1977); Ren et al (2002); Rivas et al (2003); Salwa et al (2008); Xu et al (2006).…”