Crystal Structures of Bis(diphenylglyoximato)–Nickel(II) Complex with Varying Alkoxy Chain Lengths

Abstract

Crystal structures of eight derivatives of bis(diphenylglyoximato)–nickel(II), bearing four alkoxy chains of different lengths, were determined by single-crystal X-ray crystallography. Sequential transition of packing structures by chain elongation was observed. The packing structures were typically one-dimensional columnar structure comprising metal wires, herringbone structures, quasi-layered structures and layered structures having an interdigitation of alkyl moieties in the alkoxy chains. Each structural characteristic depends on odd–even effect and alkoxy chain interactions. Additionally, the gauche conformation of the alkoxy chains contributes to filling the empty spaces of the structures, placing out of the molecular plane packing, and forming a clip structure of the alkoxy chains.

Crystal Structure of the Bis[bis(<i>p</i>-methoxyphenyl)glyoximato]nickel(II) Complex

“…3 However, four paranormal-alkoxy (-OCmH2m+1) substitutions specifically demonstrated that the columnar geometries comprising linear metal nickel wires were broken by increasing interactions between alkoxy chains in the solid state (m ≥ 4). 4 Since crystallographic studies show that para-buthoxyl (m = 4) substituted compounds exhibit polymorphism when Ni-Ni interactions are quenched, these para-substitution effects without the assistance of long alkoxy chains interactions deserve a consideration. Accordingly, we analyzed the single-crystal structure of the title compound ( Fig.…”

“…3,4 The title compound was identified by elemental analysis, as follows: Anal. found: C, 6,7 respectively, by the dual-space algorithm before being expanded by Fourier techniques.…”

“…3.2 Å). 4 The Ni···π interactions and moderate hydrogen bonds (C10···O1 iv ; ca. 3.17 Å) interlocked molecules along the c axis (Fig.…”

Effects of alkyl chain length on the cold crystallization of Schiff-base nickel(ii) complexes

“…Therefore, the structures of alkyl derivatives vary depending on the chain length. Accordingly, the alkylation of rigid molecules can alter their physical properties [1][2][3][4][5][6][7][8][9][10][11] significantly, including their thermal properties, [12][13][14][15] crystal structure, [16][17][18][19][20][21] and the structure of adsorbed monolayers. [22][23][24][25][26][27][28] We have analyzed the thermal properties of salen derivatives bearing alkyl chains of variable length and found that those with alkoxy groups adopt a liquid crystalline state at varying temperatures depending on the alkyl chain length.…”