Oxidoborates Templated by Cationic Nickel(II) Complexes and Self-Assembled from B(OH)3

Abstract

Several oxidoborates, self-assembled from B(OH)3 and templated by cationic Ni(II) coordination compounds, were synthesized by crystallization from aqueous solution. These include the ionic compounds trans-[Ni(NH3)4(H2O)2][B4O5(OH)4].H2O (1), s-[Ni(dien)2][B5O6(OH)4]2 (dien = N-(2-aminoethyl)-1,2-ethanediamine (2), trans-[Ni(dmen)2(H2O)2] [B5O6(OH)4]2.2H2O (dmen = N,N-dimethyl-1,2-diaminoethane) (3), [Ni(HEen)2][B5O6(OH)4]2 (HEen = N-(2-hydroxyethyl)-1,2-diaminoethane) (4), [Ni(AEN)][B5O6(OH)4].H2O (AEN = 1-(3-azapropyl) -2,4-dimethyl-1,5,8-triazaocta-2,4-dienato(1-)) (5), trans-[Ni(dach)2(H2O)2][Ni(dach)2] [B7O9(OH)5]2.4H2O (dach = 1,2-diaminocyclohexane) (6), and the neutral species trans-[Ni(en)(H2O)2{B6O7(OH)6}].H2O (7) (en = 1,2-diaminoethane), and [Ni(dmen)(H2O){B6O7(OH)6}].5H2O (8). Compounds 1–8 were characterized by single-crystal XRD studies and by IR spectroscopy and 2, 4–7 were also characterized by thermal (TGA/DSC) methods and powder XDR studies. The solid-state structures of all compounds show extensive stabilizing H-bond interactions, important for their formation, and also display a range of gross structural features: 1 has an insular tetraborate(2-) anion, 2–5 have insular pentaborate(1-) anions, 6 has an insular heptaborate(2-) anion (‘O+’ isomer), whilst 7 and 8 have hexaborate(2-) anions directly coordinated to their Ni(II) centers, as bidentate or tridentate ligands, respectively. The Ni(II) centers are either octahedral (1–4, 7, 8) or square-planar (5), and compound 6 has both octahedral and square-planar metal geometries present within the structure as a double salt. Magnetic susceptibility measurements were undertaken on all compounds.

Selective Electrochemical Conversion of N2 to NH3 in Neutral Media Using B, N-Containing Carbon with a Nanotubular Morphology

“…Later, powder X-ray diffraction (P-XRD) patterns were acquired for structural analysis of the precursor, wherein the high-intensity diffraction peaks for ZIB-IL match well with indexing patterns of three previously reported compounds including ZIF-8, 41 C 29 N 4 O 8 Zn 2 , 42 and C 4 H 19 B 6 N 3 O 13 Zn (0.5 H 2 O). 43 As seen in Figure S5, the highest intensity peak at 11.6°corresponds to the (201) plane of C 29 N 4 O 8 Zn 2 . Also, other distinct sharp peaks at 7.4, 10.5, 12.6, 16.4, and 21.02°reveal the presence of (110), (200), (211), (310), and (400) planes of ZIF-8 although the peaks at 13.6 and 23.5°correspond to (400) and (022) planes in C 4 H 19 B 6 N 3 O 13 Zn (0.5 H 2 O), respectively.…”

Structural Regulation and Oxygen Reduction Reaction Activity of [Co(bpy)2BO2(OH)] and [Cu(bpy)(OH)]2– Complex Templated Borates

“…1−6 B can be bonded with O to form BO 3 and BO 4 units, which are the primary building units of borates. If these two kinds of units connect with each other by shared O atoms, different polyanions could be formed, as is known, some of which have been reported, such as [B 3 O 3 (OH) 4 ] − , 7 [B 4 O 5 (OH) 4 ] 2 − , 8 and [B 5 O 6 (OH) 4 ] −-. 9 More importantly, these units can polymerize in pairs to produce polyatomic clusters.…”

Novel application of imidazole-based ligand-templated borates in a zinc–air battery

“…Due to its special conformation and various charge properties, using metal complexes as templates is considered to be a very effective synthetic method. [22][23][24][25] Based on the abundant electron density and excellent hole transport effect of the imidazole ring ligand, metal ions (Ni 2+ and Co 2+ ) can combine with the nitrogen atoms of the imidazole ring ligand and oxygen atoms of the boron-oxygen skeleton to form a sixcoordinated structure. 26,27 The oxygen/hydroxyl groups in the skeleton are connected via hydrogen bonds (H-Bs) to form a virtual large ''cavity'' structure, which is essential for exposing more active sites and provides a good structural basis for subsequent ORR performance.…”