A novel helical chainlike cobalt(II) coordination polymer containing 1D trigonal channels: Synthesis, crystal structure and properties

Abstract

A novel helical-chain coordination polymer [Co(tau) 2 (4,4′-bipy)] n ·nH 2 O 1 (tau = taurine, 4,4′-bipy = 4,4′-bipyridine) has been hydrothermally synthesized and characterized by infrared spectroscopy, and thermogravimetric analysis, magnetic measurements, solid-state CD spectra and single crystal X-ray diffraction analysis. The intertwist trigonal-fold helical chains are further connected through hydrogen bonds to give a three-dimensional supramolecular network, in which trigonal microporous channels filled with water guest molecules exist within the polymer coils. Compound 1 shows weak antiferromagnetic interactions among metal ions.The current interest in the crystal engineering of coordination polymer frameworks not only stems from their potential applications as new functional materials, but also because of their intriguing variety of architectures and topologies 1 . Among the numerous metal-organic coordination polymers, the construction of helical coordination polymers has generated a great deal of attention because helical structures are ubiquitous in nature and of fundamental importance in biological systems 2 . So it is a fascinating challenge for chemists to control the formation of helicity at the supramolecular level. In many cases, chiral coordination polymers are prepared with chiral ligands to introduce chirality to the structure or using chiral arrangement of achiral components to form a chiral structure. Nevertheless, it is still a challenge to predict the exact structures and compositions of polymeric compounds assembled in a helical motif, although an increasing