TY - JOUR

T1 - Synthesis and characterization of polyborates templated by cationic copper(II) complexes: structural (XRD), spectroscopic, thermal (TGA/DSC) and magnetic properties

AU - Altahan, Mohammed

AU - Beckett, Michael

AU - Coles, Simon

AU - Horton, Peter N.

PY - 2017/10/15

Y1 - 2017/10/15

N2 - Several polyborate containing species templated by cationic copper(II) coordination compounds have been synthesized. The ionic species [Cu(en)2][B5O6(OH)4]2.2H2O (en = 1,2-diaminoethane) (1), [Cu(dmen)2(H2O)][B5O6(OH)4]2.3H2O (dmen = N,N-dimethyl-1,2-diaminoethane) (2), [Cu(pn)2{B5O6(OH)4}][B5O6(OH)4].4H2O (pn = 1,2-diaminopropane) (3), [Cu(dach)2(H2O)2][Cu(dach)2][B7O9(OH)5]2.4H2O (dach = 1,2-diaminocyclohexane) (4), and the neutral species [Cu(dmen){B6O7(OH)6}].4H2O (5) and [Cu(tmeda){B6O7(OH)6}].6H2O (tmeda = N,N,N',N'-tetramethyl-1,2-diaminoethane) (6) have been synthesized in aqueous solution and characterized by spectroscopic and thermal (TGA/DSC) methods. The previously prepared compound [Cu(en)2][B4O5(OH)4]2.2B(OH)3 (7) has also been prepared by an alternative route. Compounds 1-6 have been further characterized by single-crystal XRD studies. The new compounds show extensive H-bond interactions and display a range of structural features: 1-3 have isolated pentaborate(1-) anions whilst 4 possesses an isolated heptaborate(2-) anion. In addition, 3 has a pentaborate(1-) and 5 and 6 have hexaborate(2-) anions directly coordinated to their copper(II) centers, in mondentate and tridentate manners, respectively. The copper(II) centers show a variety of coordination numbers and geometries: square-planar (1, 7), octahedral (4) and square-based pyramidal (2, 3, 5, 6). Thermal studies (TGA/DSC) and magnetic susceptibility measurements have been undertaken on all compounds.

AB - Several polyborate containing species templated by cationic copper(II) coordination compounds have been synthesized. The ionic species [Cu(en)2][B5O6(OH)4]2.2H2O (en = 1,2-diaminoethane) (1), [Cu(dmen)2(H2O)][B5O6(OH)4]2.3H2O (dmen = N,N-dimethyl-1,2-diaminoethane) (2), [Cu(pn)2{B5O6(OH)4}][B5O6(OH)4].4H2O (pn = 1,2-diaminopropane) (3), [Cu(dach)2(H2O)2][Cu(dach)2][B7O9(OH)5]2.4H2O (dach = 1,2-diaminocyclohexane) (4), and the neutral species [Cu(dmen){B6O7(OH)6}].4H2O (5) and [Cu(tmeda){B6O7(OH)6}].6H2O (tmeda = N,N,N',N'-tetramethyl-1,2-diaminoethane) (6) have been synthesized in aqueous solution and characterized by spectroscopic and thermal (TGA/DSC) methods. The previously prepared compound [Cu(en)2][B4O5(OH)4]2.2B(OH)3 (7) has also been prepared by an alternative route. Compounds 1-6 have been further characterized by single-crystal XRD studies. The new compounds show extensive H-bond interactions and display a range of structural features: 1-3 have isolated pentaborate(1-) anions whilst 4 possesses an isolated heptaborate(2-) anion. In addition, 3 has a pentaborate(1-) and 5 and 6 have hexaborate(2-) anions directly coordinated to their copper(II) centers, in mondentate and tridentate manners, respectively. The copper(II) centers show a variety of coordination numbers and geometries: square-planar (1, 7), octahedral (4) and square-based pyramidal (2, 3, 5, 6). Thermal studies (TGA/DSC) and magnetic susceptibility measurements have been undertaken on all compounds.

U2 - 10.1016/j.poly.2017.07.016

DO - 10.1016/j.poly.2017.07.016

M3 - Article

VL - 135

SP - 247

EP - 257

JO - Polyhedron

JF - Polyhedron

SN - 0277-5387

ER -