Synthesis and characterization of new coordination compounds by the use of 2-pyridinemethanol and di- or tricarboxylic acids

Abstract

The development of synthetic approaches towards new coordination polymers has attracted significant interest due to their fascinating physical properties, as well as their use in a wide range of technological, environmental and biomedical applications. Herein, the initial combination of 2-pyridinemethanol (Hhmp) with 1,4-benzenedicarboxylic acid (H₂bdc) or 1,3,5-benzenetricarboxylic acid (H₃btc) has been proven a fruitful source of such new species providing access to five new coordination compounds, namely [M₂(Hbtc)₂(Hhmp)₄]·DMF (M = Co^II, 1·DMF;Ni^II, 2·DMF), [Ni(bdc)(Hhmp)₂]_n·4H₂O (3·4H₂O), [Zn₂(bdc)(hmp)₂]_n·DMF (4·DMF) and [Fe₃(bdc)₃(Hhmp)₂]_n (5). 4·DMF and 5 are the first metal–organic frameworks (MOFs) based on Hhmp with 4 exhibiting an unprecedented 4,4,4-c net with the point symbol {3²·10³·11}{3²·10⁴}₂. The framework of 5 is based on a linear Fe^II₃ SBU and possesses a 3,4,6T2 topology with the point symbol {4²·8³·10}₃{4³}₂{4⁶·8⁶·10³}. DC magnetic susceptibility measurements were carried out in 5 and revealed the existence of antiferromagnetic coupling between the Fe^II cations with a superexchange value of J = −8.46 cm⁻¹.