Acetato and formato copper(II) paddle-wheel complexes with nitrogen ligands

Copper(II) Complex of a Urea‐functionalized Pyridyl Ligand: Synthesis, Crystal Structure, and Acetate Binding Properties

“…The copper atom (Cu1) is slightly out of the square plane of oxygen atoms (0.207 Å), which is consistent with the theory that the longer the Cu ··· Cu distance within the dimer, the higher the Cu out‐of‐plane deviation . In complex 1 , the Cu1 ··· Cu1 i distance is 2.6432(11) Å, which falls into the same order of magnitude as described in the literature (2.612–2.713 Å) . Adjacent complex 1 units are held together by the C–H ··· O hydrogen bonds [C4 ··· O1 iii , 3.362(6) Å, C4–H4 ··· O1 iii , 144.5°, Figure c and Table ], forming a hydrogen bond chain structure including paddle‐wheel units.…”

Reactivity of homoleptic and heteroleptic core paddle wheel Cu(II) compounds

“…Compound 6 has the apical units (Cu1-O9) at 2.1540(15) Å while compound 7 (Cu1B-N1B) at 2.243(8) Å. The remaining Cu-O distances of the basal plane are in the range 1.959(6) Å and 1.982(7) Å, which are shorter than apical N atoms due to the Jahn-Teller effect [45] but comparable to similar paddle-wheel structures described in the literature (1.945 Å to 2.008 Å) [17,22,[46][47][48][49][50][51].…”

“…The Cu••Cu intermolecular distances are 2.6057(5) Å and 2.656(1) Å, (6 and 7, respectively). In 6, this Cu••Cu distance is a little bit shorter than other similar structures (2.610 Å-2.713 Å) [17,22,[45][46][47][48][49][50]. It is worthwhile to mention that compound 7 presents the largest angle (O2A-Cu1A-N1A, 99.40°), which corresponds to the carboxylate oxygen closest to the 2-Bzpy ligand.…”

“…Herein, we focus on this novel compound with an heteroleptic paddle-wheel core [Cu(μ-Pip)(μ-OAc)(MeOH)]2 (1) (OAc=acetate), recently obtained in our research group [18]. Homoleptic core paddlewheel have been vastly used as starting building units for the design of supramolecular [6] or polymeric [22] architectures while there is not any research with those containing a heteroleptic paddlewheel core. Herewith, the reactivity of 1 with pyridine/pyrazole derivative ligands (pyridine (py, 2); 3phenylpyridine (3-Phpy, 3); 4-acetylpyridine (4-Acpy, 4) and 3,5-dimethylpyrazole (3,5-dmpz, 5)) have been studied, resulting in monomeric compounds [Cu(Pip)2(dPy)2(H2O)] (2)(3)(4)(5).…”

Crystal structure and spectroscopic properties of polymeric adducts of the tetra-μ-haloaspirinate-dicopper(II)

“…The linear polymeric structure of 4 is similar to that found for {[Cu 2 (-MeCOO) 4 ](-2,5-Me 2 Pyrz)} n [48], demonstrating an interesting trend for dinitrogen C 4 H 4 N 2 hetero-cyclic axial ligands of paddle-wheel acetate and formate complexes. Steric hindrance leads to binuclear complexes for pyridazine which has two N-atoms at 1,2 positions, while pyrimidine with two nitrogen atoms at 1,3 positions afforded a zig-zag polymeric chain [49]. Not surprisingly, our pyrazine (having two nitrogen atoms at opposite (1,4) ring locations) leads to a linear polymer.…”