A two-fold interpenetrated flexible bi-pillared-layer framework of Fe(II) with interesting solvent adsorption property

摘要

A two-fold interpenetrated microporous bi-pillared-layer framework of Fe(II), {[Fe(2,6-napdc)(4,4′-bipy)](EtOH)(H2O)} n (1) (2,6-napdc = 2,6-naphthalenedicarboxylate; 4,4′-bipy = 4,4′-bipyridine) composed of mixed ligand system has been synthesized and structurally characterized. The 2,6-napdc linkers form a 2D corrugated sheet of {Fe(2,6-napdc)} n by linking the secondary building unit of Fe2(CO2)2 in the ac plane, which are further connected by double 4,4′-bipy pillars resulting in a bi-pillared-layer type 3D framework. The 3D framework is two-fold interpenetrated and exhibits a 3D channel structure (4.0 × 3.5, 1.5 × 0.5 and 2.2 × 2.1Å2) occupied by the guest water and ethanol molecules. Framework 1 shows high thermal stability, and the desolvated framework (1 $^{boldsymbolprime}$ ) renders permanent porosity realized by N2 adsorption profile at 77K (BET surface area of ~52 m2 g − 1). Moreover, the framework 1 $^{boldsymbolprime}$ also uptakes different solvent vapours (water, methanol and ethanol) and their type-I profile suggest strong interaction with pore surfaces and overall hydrophilic nature of the framework. Temperature dependent magnetic measurements suggest overall antiferromagnetic behaviour in compound 1.