Single pot reaction of Co(III) and Ni(II) hydrogen-bonded organic frameworks and multidisciplinary application in dye adsorption, separation and DNA binding.

Two hydrogen-bonded organic frameworks (HOFs) of formula Co(C 6 H 5 N 2 O) 3 (1) and [Ni(C 6 H 6 N 2 O) 3 ·H 2 O·ClO 4 (2) were synthesized by single pot reaction from the respective Syn-2-pyridinealdoxine (2-pdad) with separate reaction of Co(acac) 2 and Ni(ClO 4) 2 in MeOH. X-ray crystallography exposes that (1) and (2) crystallized in orthorhombic and monoclinic space group with Pbca and P 2 1 / c point group, respectively. In both complexes, the central metal atoms are surrounded by three molecules of 2-pdad through chelation with the nitrogen atom of the aldoxin moiety and form a hexa-coordinated octahedral complex. Complexes (1) and (2) have van der Waals interaction, intra and intermolecular hydrogen bonding and rare 3D pillar layer HOFs network. However, both complexes adsorbed Rhodamine B (RhB) compared to other dyes i.e methylene blue and methyl orange. The % of adsorption efficiency of RhB is high in presence of complex 1 , whereas complex (2) has a high efficiency for separation of dye molecule (RhB and MB). Moreover, the UV absorption spectrum of (1) and (2) was measured and maximum absorption peaks appeared at 224 nm and 280 nm, which suggest that the cobalt (III) complex bind to DNA via an intercalation binding mode whereas nickel (II) complex cannot bind to DNA. DFT Study observed that complex 1 (singlet) has the highest ionisation potential energy and softness and lowest stability and hardness compared to complex 2 (singlet or triplet). Image 1 • Synthesis of novel Co(C 6 H 5 N 2 O) 3 (1) and [Ni(C 6 H 6 N 2 O) 3 ·H 2 O·ClO 4 (2) complex. • Multidisciplinary application: Dye adsorption, Separation and DNA binding. • Both the complexes produce 3D pillar layer HOFs network. • Complex (2) has a high efficacy for separation of mixture of dye molecule (RhB and MB). • Complex 1 has binding ability to DNA whereas complex 2 has no DNA binding activity. • DFT Study: Complex 1 (singlet) has the highest ionisation potential energy, softness and lowest stability, hardness. [ABSTRACT FROM AUTHOR]