Diaquabis(2,2′-biimidazole)cobalt(II) 4,4′-dicarboxybiphenyl-3,3′-dicarboxylate

Abstract

Key indicators: single-crystal X-ray study; T = 293 K; mean (C-C) = 0.003 Å; R factor = 0.033; wR factor = 0.087; data-to-parameter ratio = 11.5.In the title compound, [Co(C 6 H 6 N 4 ) 2 (H 2 O) 2 ](C 16 H 8 O 8 ), the Co II cation and the organic anion occupy different crystallographic inversion centres and, as a consequence, the asymmetric unit comprises two half-molecules. The benzene groups are coplanar. The four coordinating N atoms of the two bidentate biimidazole ligands define the equatorial plane of a slightly distorted octahedral CoO 2 N 4 geometry, and the water O atoms lie in the axial coordination sites. Translational (a,b) and inversion-related symmetry operations link the Co complex molecules and the negatively charged carboxylate anions via intermolecular N-HÁ Á ÁO and O-HÁ Á ÁO hydrogen bonds into sheets parallel to (101). The coordinated water molecules connect the sheets through O-HÁ Á ÁO hydrogen bonds, forming a three-dimensional framework. In addition, two intramolecular O-HÁ Á ÁO hydrogen bonds are observed between the carboxyl and carboxylate groups. Related literature ExperimentalCrystal data [Co(C 6

Diversity of coordination modes in the polymers based on 3,3′,4,4′-biphenylcarboxylate ligand

“…However, the combination of bidentate bridging mode with monodentate mode is still rarely observed [43] and is different from that in 1. In 2-4, the common form for 3,4-H 2 bptc 2 À ligand with the 4,4 0 -carboxyl groups protonated and the 3,3 0 -carboxyl groups deprotonated [43,[46][47][48][51][52][53][54] are observed. However, the coordination mode are different from the most common adoption in the references, which utilize one Fig.…”

“…They are the more common forms of the deprotonated anions for 3,4-H 4 bptc that have ever been observed, including 3,4-bptc 4 À [43,45,47,49,50,[54][55][56][57][58], 3,4-H 2 bptc 2 À [42][43][44][46][47][48][51][52][53][54], and 3,4-H 3 bptc À [49]. In compound 1, the 3,4-bptc 4 À ligand displays a new coordination mode in the 3,4-bptc 4 À based system.…”

“…Among them, polycarboxylates have caught the long lasting research attention, due to their variety coordination modes and structural features, such as 1,2-benzenedicarboxylate, 1,4-benzenedicarboxylate, 1,3,5-benzenetricarboxylate, and 1,2, 4,5-benzenetetracarboxylate, which all have been extensively employed in the construction of metal-organic polymers displaying variety structures and interesting properties [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. So far, many efforts have been focused on the employment of flexible or the V-shaped multidentate organic bridging ligands [30][31][32][33][34][35][36][37][38][39][40], while the influence of the size of the rigid aromatic multidentate ligands on the formation of the ultimate framework have rarely been studied [41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57]...…”

Syntheses, structures, and magnetism of two coordination compounds with 3,3′,4,4′-biphenyltetracarboxylic acid and 1,10-phenanthroline

“…Considerable efforts have been devoted to developing flexible or V-shaped multidentate bridging ligands [30][31][32][33][34][35][36][37][38][39][40]. However, the nature of the rigid aromatic multidentate ligands to form the overall configuration has been scarcely investigated so far magnetic study of the transition metal coordination polymers bridged by carboxylate ligand [42][43][44][45][46][47][48][49][50][51][52][53][54][55]. In this regard, 3,3 0 ,4,4 0 -biphenyltetracarboxylic acid (3,4-H 4 bptc) was examined to take advantage of unique features of hydroxypolycarboxylic acids: (1) versatile coordination behavior from completely or partially deprotonated acid; (2) polycarboxylics are nonchelating, chelating, bridging, and hydrogen-bond acceptors and donors to form extended structures; (3) two phenyl rings can be rotated around the C-C single bond [42,56].…”