Syntheses, structures, and magnetic characterizations of cyanide-bridged Fe^IIIMn^IIIchains constructed by mer-Fe(iii)tricyanide and Mn(iii) Schiff bases: Magnetostructural relationship

Abstract

Five Fe(III)Mn(III) bimetallic compounds [Fe(iqc)(CN)(3)][Mn(5-Xsalen)]·pMeOH·qMeCN·rH(2)O [Hiqc = N-(quinolin-8-yl)isoquinoline-1-carboxamide; salen = N,N'-ethylenebis(salicylideneiminato) dianion; X = H(2), F(3, 3a), Cl(4), Br(5)] were prepared by assembling a newly designed mer-Fe tricyanide (Ph(4)P)[Fe(iqc)(CN)(3)]·0.5H(2)O (1) and the respective Mn Schiff bases Mn(5-Xsalen)(+). Compounds 2-4 show linear chain structures in which trans-positioned cyanides of the Fe precursor bridge neighbouring Mn atoms, while 5 is a zigzag chain coordination polymer where two cyanide groups of the precursor in the cis mode act as bridges. The structural change from linear to zigzag may arise from the size effect of the halogens. The reversible structural transformation occurs between 3 and 3a upon the solvation-desolvation protocol and the corresponding magnetic behaviours are affected. Furthermore, in 4 and 5, the helical chains are established through hydrogen bonding of solvent molecules. From a magnetostructural point of view, within the linear chain system, the ferromagnetic coupling in 2, contrary to antiferromagnetic interactions in 3-4, is associated with the large torsion angle of C(eq)-Fe-Mn-N(O)(eq) (eq = equatorial) as well as almost the linear Mn-N≡C angle.

Solvolthermal synthesis, structure, and properties of a novel dinuclear zinc(II) complex

“…In recent years, much work has been carried out on the syntheses and properties of Schiff bases and their complexes [1][2][3][4][5]. You and co workers have prepared some Schiff base complexes with solvolthermal method [6][7][8].…”

Supramolecular self-assembly and crystal structures of new zinc(II) complexes derived from 4-Methyl-2-[(2-methylaminoethylimino)methyl]phenol

“…1b (1), H(4)···N(12) iii 2.68 (3), N(4)···N(12) iii 3.559(9) Å, N(4)-H(4)···N (12) iii 163(6)°; symmetry codes: ii 1 -x, 1 -y, -1 -z; iii 3/2 + x, -1/2 -y, z), forming a 3D network (Fig. 2b).…”

“…In recent years, much work has been carried out on the syntheses and properties of Schiff bases and their complexes [1][2][3][4][5]. Schiff bases derived from salicylaldehyde and primary amines con stitute one of the most relevant synthetic ligand sys tems with importance in asymmetric catalysis and they appear to be of importance for a broad range of transition metal catalyzed reactions including lactide polymerization, epoxidation of olefins, hydroxylation and asymmetric ring opening of epoxides [6][7][8][9][10].…”

Various Structural Types of Cyanide-Bridged FeIII–MnIII Bimetallic Coordination Polymers (CPs) and Polynuclear Clusters Based-on A New mer-Tricyanoiron(III)Building Block: Synthesis, Crystal Structures, and Magnetic Properties

“…Up to now, many 0D discrete clusters and 1D infinite coordination polymers have been successfully obtained by assembling the decorated polycyanometallates such as the blocked trans -dicyano-, fac -tricyano-, mer -tricyano- and tetracyanometallate, and the paramagnetic compound with or without the auxiliary ligand [18,19,20,21,22,23]. Several reports from our and other groups on the mer -[Fe(L](CN) 3 ] -/2- -based cyanide-bridged complexes, where L represents the equatorial in-plane ligands with relative large steric effect for efficiently lowering the dimensionality of the target complex such as bis (2-pyridylcarbonyl)amidate (bpca) [24,25], 8-(pyridine-2-carboxamido)quinoline (pcq) [26,27,28], 8-(pyrazine-2-carboxamido)quinoline (pzcq) [29], 8-(5-methylpyrazine-2-carboxamido)quinoline (mpzcq) [30], 8-(2-quinoline-2-carboxamido)quinoline (qcq) [31], N -(quinolin-8-yl)isoquinoline-1-carboxamide anion (iqc) [32], and bis (2-benzimidazolyl)pyridine (bbp) [33,34] showed that the mer -[Fe(L](CN) 3 ] -/2- type precursors are excellent candidates for constructing interesting magnetic assemblies. Here, a new structurally characterized mer -tricyanoiron(III) building block 1 (Scheme 1) was first employed to assemble with the manganese Schiff base compounds (Scheme 1), leading to a series of new CN-bridged Fe(III)-Mn(III) complexes with various structural types formulated as {[Fe(qxcq)(CN) 3 ][Mn(L 1 )(H 2 O)]}[Mn(L 1 )(H 2 O)(CH 3 OH)](ClO 4 )·1.5MeOH·0.5H 2 O (L 1 = N,N′-bis (3-methoxy-5-bromosalicylideneiminate) (2), {[Fe(qxcq)(CN) 3 ][Mn(L 2 )]} 2 ·0.5H 2 O (L 2 = N,N′ -ethylene- bis (3-ethoxysalicylideneiminate)) (3), [Fe(qxcq)(CN) 3 ][Mn(L 3 )] (L 3 = bis (acetylacetonato)ethylenediimine) (4), and [Fe(qxcq)(CN) 3 ][Mn(L 4 )]·1.5MeOH·0.5CH 3 CN·0.25H 2 O (L 4 = N,N′ -(1,1,2,2-tetramethylethylene)bis(salicylideneiminate)) ( 5 ).…”