Dinuclear, star-shaped tetranuclear and trinuclear-based two-dimensional metal complexes derived from a less investigated Schiff base ligand: Syntheses, crystal structures and spectroscopic correlation

Mononuclear and heterometallic dinuclear, trinuclear and dimer-of-dinuclear complexes derived from single- and double-compartment Schiff base ligands having a less utilized diamine

“…Two new mononuclear copper(II)/nickel(II) and six new heterometallic complexes of the following types are reported: two diphenoxo-bridged Cu II (U VI O 2 ) (1 and 2), one diphenoxo-bridged Ni II (U VI O 2 ) (3), one dimer-ofdinuclear [Cu II Ag I ] 2 (4) where two diphenoxo-bridged Cu II Ag I units are interlinked by an Ag I -C (g 2 arene) bond and silver(I)ÁÁÁÁsilver(I) interaction, one dimer-of-dinuclear [Cu II Ag I ] 2 (5) where two diphenoxo-bridged Cu II Ag I units are interlinked by Cu II Á Á ÁO(nitrate) semi-coordination and silver(I)Á Á Ásilver(I) interaction and one trinuclear linear Cu II Cd II Cu II compound (6) where copper(II) and cadmium(II) in each of the two Cu II Cd II pairs are bridged by two phenoxo oxygen atoms and two oxygen atoms of a perchlorate ligand. Major outcomes may be summarized as follows: (i) compounds 1-3 are among only a few 3d-uranyl compounds from single-/double-compartment Schiff base ligands [1,[74][75][76][77][78][79][80]; (ii) compound 3 is the sole example of a dinuclear Ni II (U VI O 2 ) system from single-/double-compartment Schiff base ligands [1]; (iii) compounds 4 and 5 are among only a few 3d-silver(I) compounds from single-/double-compartment Schiff base ligands [1,46,49]; (iv) compound 4 is the sole example of a dimer-of-dinuclear [Cu II Ag I ] 2 system where two diphenoxo-bridged Cu II Ag I units are interlinked by the simultaneous effect of a Ag I -C bond and a silver(I)ÁÁÁÁsilver(I) interaction [1]; (v) compound 6 is among just a few examples of discrete trinuclear Cu II Cd II Cu II systems from single-/double-compartment Schiff base ligands [1,30,47]; (vi) the bis(l-phenoxo)-l-perchlorate bridging moiety in compound 6 is new in 3d-cadmium(II) systems from single-/double-compartment Schiff base ligands [1]; (vii) an interesting structural aspect is found in the Cu II (U VI O 2 ) compounds-the two phenyl rings in the Cu II (U VI O 2 ) compounds become less planar in comparison to those of the corresponding mononuclear copper(II) compound derived from a single-compartment ligand, while the situation is reversed for the double-compartment ligands; (viii) the correlation of the d-d band position of copper(II) with the displacement of copper(II) from the least-squares basal plane has been checked and it has been found that the correlation is not straightforward.…”

“…A few compounds containing both a bivalent 3d metal ion of either Cu II and Ni II and the 5f metal ion U VI O 2 have been previously reported for double-compartment Schiff base ligands (3-methoxy/ [1,[74][75][76][77][78][79][80]. Most of those compounds which are derived from H 2 L double are cocrystals in which the uranium(VI) center is not coordinated with the phenoxo or methoxy/ethoxy/3-hydroxy oxygen atoms or Schiff base ligand [1,[76][77][78], while all of those compounds which are derived from H 2 L single are discrete dinuclear systems in which the uranium(VI) center is coordinated with the two phenoxo oxygen atoms [74,75], i.e., those are diphenoxo-bridged, as are the three compounds 1-3 in the present investigation.…”

“…Most of those compounds which are derived from H 2 L double are cocrystals in which the uranium(VI) center is not coordinated with the phenoxo or methoxy/ethoxy/3-hydroxy oxygen atoms or Schiff base ligand [1,[76][77][78], while all of those compounds which are derived from H 2 L single are discrete dinuclear systems in which the uranium(VI) center is coordinated with the two phenoxo oxygen atoms [74,75], i.e., those are diphenoxo-bridged, as are the three compounds 1-3 in the present investigation. On the other hand, only one of the compounds derived from H 2 L double (the concerned ligand is 3-ethoxysalicylaldehyde-1,3-diaminopropane, H 2 L 8 ; Table 3) is a discrete dinuclear systems in which the uranium(VI) center is also coordinated with the two phenoxo oxygen atoms (i.e., also diphenoxo-bridged), but not coordinated with the ethoxy oxygen atoms.…”

“…On the other hand, only one of the compounds derived from H 2 L double (the concerned ligand is 3-ethoxysalicylaldehyde-1,3-diaminopropane, H 2 L 8 ; Table 3) is a discrete dinuclear systems in which the uranium(VI) center is also coordinated with the two phenoxo oxygen atoms (i.e., also diphenoxo-bridged), but not coordinated with the ethoxy oxygen atoms. For all of those few diphenoxo-bridged discrete dinuclear 3d-uranyl(VI) compounds, the 3d metal ion is copper(II) and the general composition ( (3) are among only a few examples of dinuclear 3d-uranyl(VI) compounds and 3 is the only example of a discrete dinuclear nickel(II)-uranyl(VI) compound derived from the above mentioned single/double-compartment Schiff base ligands [1,[74][75][76][77][78][79][80].…”

Dimeric, Two‐Dimensional and Metal‐Centered Rectangular Heterometallic CuII–AgI/CdII/BaII Systems Derived from a Single Compartmental Ligand

“…Above mentioned single‐ or double‐compartmental ligands having two or three carbon atoms between two imine nitrogen atoms were much more explored in comparison to those having four carbon atoms between the two imine nitrogen atoms. With the aim to explore the metal complexes from the latter ligands, we already showed some interesting features on both structures and properties in a series of M II Cu II 3 stars (M=Cd, Zn, Cu, Ni, Mn),, where the particular ligand is N,N′‐bis(salicylidene)‐1,4‐butanediamine (H 2 L; Scheme ). In contrast to the ligands having two or three carbon atoms between the two imine nitrogen atoms, H 2 L provides an appreciably distorted N(imine) 2 O(phenoxo) 2 compartment to copper(II) center, which is the origin of some interesting features on structures and magnetic properties.…”