Synthesis and crystal structure of a one-dimensional chain-like strontium(II) coordination polymer built of N-methyldi-ethano-lamine and isobutyrate ligands.

The one-dimensional coordination polymer (I) [Sr(ib)(2)(H(2)mda)] (n) (Hib = isobutyric acid, C(4)H(8)O(2), and H(2)mda = N-methyldi-ethano-lamine, C(5)H(13)NO(2)), namely, catena-poly[[(N-methyldi-ethano-lamine-κ(3) O,N,O')strontium(II)]-di-μ(2)-isobutyrato-κ(3) O,O':O;κ(3) O:O,O'], was prepared by the one-pot aerobic reaction of [Zr(6)O(4)(OH)(4)(ib)(12)(H(2)O)]·3Hib with Sr(NO(3))(2) and H(2)mda in the presence of MnCl(2) and Et(3)N in aceto-nitrile. The use of MnCl(2) is key to the isolation of I as high-quality colorless crystals in good yield. The mol-ecular solid-state structure of I was determined by single-crystal X-ray diffraction. Compound I crystallizes in the monoclinic space group P2(1)/c and shows a one-dimensional polymeric chain structure. Each monomeric unit of this coordination polymer consists of a central Sr(II) ion in the NO(8) coordination environment of two deprotonated ib(-) ligands and one fully protonated H(2)mda ligand. The C and O atoms of the H(2)mda ligand were refined as disordered over two sets of sites with site occupancies of 0.619†(3) and 0.381†(3). Compound I shows thermal stability up to 130°C in air.