Structural Chemistry and Properties of Metal Oxalates Containing a Long-Spanning Dipyridyl Ligand: Chain, Interpenetrated Diamondoid, Threaded-Loop Layer, and Self-Penetrated Topologies

Abstract

Hydrothermal reaction of metal oxalate (ox) salts and bis­(4-pyridylmethyl)­piperazine (bpmp) afforded a series of coordination polymers that were structurally characterized by single-crystal X-ray diffraction. {[Cd­(H2O)4(bpmp)]­(ox)} n (1) and {[Co­(H2O)4(bpmp)]­(ox)} n (2) show isostructural cationic one-dimensional (1D) coordination polymer chain motifs with unligated ox anions. A higher temperature polymorph of 2, {[Co­(ox)­(bpmp)]·3H2O} n (3), possesses a system of threefold interpenetrated three-dimensional (3D) diamondoid nets. {[Mn­(H2O)4(bpmp)] [Mn2(ox)3]·5H2O} n (4) manifests a unique 1D + 2D → 3D polyrotaxane coordination polymer structure with 1D cationic [Mn­(H2O)4(bpmp)] n chains threaded through apertures coursing through parallel stacks of anionic [Mn2(ox)3] n two-dimensional (2D) hexagonal layers. {[Cu2(ox)2(bpmp)]·6H2O} n (5) possesses 2D [Cu2(ox)2] n layers pillared by bpmp ligands into a 3D [Cu2(ox)2(bpmp)] n coordination polymer network with an unprecedented 4,4-connected self-penetrated (5383)2(5482) topology. Variable temperature magnetic susceptibility studies showed weak antiferromagnetic coupling along [Co­(ox)] n chain submotifs in 3 with concomitant zero-field splitting (J = −4.1(7) cm–1, D = 34.5(6) cm–1), weak antiferromagnetic coupling within the [Mn2(ox)3] n hexagonal layers in 4 (J ∼ −0.5 cm–1), and strong antiferromagnetic coupling within the 2D [Cu2(ox)2] n layers in 5 (J = −220(6) cm–1).

Mechanistic insight into novel sulfoxide containing SABRE polarisation transfer catalysts

“…Nonetheless, the structure of 6 reflects a common binding mode of oxalate with transition metals. 63,65,66 Experimental All NMR measurements were carried out on a 400 MHz Bruker Avance III spectrometer using solutions at room temperature (298 K) unless otherwise stated. Para-hydrogen ( p-H 2 ) was produced by passing hydrogen gas over a spin-exchange catalyst (Fe 2 O 3 ) and used for all hyperpolarisation experiments.…”

Interpenetrated and Catenated Zinc Thiosulfates Frameworks with dia and qtz Nets: Synthesis, Structure, and Properties

“…It has been known that three important structures, viz, the diamond ( dia ), the SrAl 2 ( sra ), and the quartz ( qtz ) net represent hybrid structures based on tetrahedral node. − Presently, we have isolated the diamond net ( II and III , (SI, Figure S24a,b) and the quartz net ( IV ). In addition, it can be noted that the compositions of III and IV are the same, but a closer look at the connectivity within the structure reveals subtle differences.…”

“…The diamondoid structure is generally observed where the participating nodes are tetrahedral in nature. The diamondoid structures have been observed commonly in many metal–organic framework hybrid compounds. − Here, the Zn­(II) ions acts as the tetrahedral node (coordinated with two bpy and two S 2 O 3 2– units). The connectivity between Zn, S 2 O 3 , and bpy gives rise to an adamentane type unit, which is common for all the diamondoid networks (Figure a).…”

Two-Dimensional Metal-Organic Framework Materials: Synthesis, Structures, Properties and Applications

“…607 The MOF [Mn(H 2 O) 4 (bpmp)][Mn 2 (ox) 3 ]• 5H 2 O (bpmp = bis(4-pyridylmethyl)piperazine) also features similar polythreading of anionic 2D hexagonal sheets by 1D cationic chains. 608 610 Zhang and co-workers illustrated two supramolecular isomers with stoichiometry [Cu 2 (pz)(CN) 2 ]•[CuCN] featuring 3D polypseudorotaxane structures by the penetration of 2D [Cu 2 (pz)(CN) 2 ] sheets with 1D [Cu(CN)] chains. One isomer exhibits (3,4)-connected Shubnikov-type (5, 3 4 ) sheets arranged in ABAB mode while the other with typical (6,3)connected brick wall layers arranged in ABBA mode (Figure 106).…”

“…Similar interesting feature is also observed in [Ag­(bpp)]­[Ag 2 (bpp) 2 (ox)]­(NO 3 ) in which (6,3)-connected 2D sheets are threaded by 1D cationic chains (Figure b) . The MOF [Mn­(H 2 O) 4 (bpmp)]­[Mn 2 (ox) 3 ]·5H 2 O (bpmp = bis­(4-pyridylmethyl)­piperazine) also features similar polythreading of anionic 2D hexagonal sheets by 1D cationic chains . Another example of ionic polypseudorotaxane structure is [Zn­(2-stp)­(bpy)­(H 2 O)­(H 2 O) 0.25 ] 2 [Zn­(bpy)­(H 2 O) 4 ]·4H 2 O (2-stp = 2-sulfoterephthalate), with 2D corrugated anionic sql sheets stacked in AA mode penetrated by 1D linear cationic chains to form 3D architecture with unprecedented (3,4,4)-connected topology .…”