Synthesis, IR-, NMR-, DFT- and X-ray analysis of novel C2-chiral diferrocenyl–salen complexes

Iron(iii) and nickel(ii) complexes as potential anticancer agents: synthesis, physicochemical and structural properties, cytotoxic activity and DNA interactions

“…All the coordination bond distances are in accordance with the literature values. [56][57][58][59][60][61] The angles of O1-Fe1-N3 and O3-Fe1-N1 are 149.05 (18) and 146.07(19)1, respectively. Clearly, the Fe III center deviates from the basic plane of the quadrangle pyramid.…”

NiIIand CuIIcomplexes of a salen ligand bearing ferrocenes in its secondary coordination sphere

“…This conguration has been observed previously via crystallography for structurally similar compounds in which two ferrocene moieties are also attached on a diimine linker, and is expected due to their steric bulk. 51 Both M(Sal) Fc exhibit calculated coordinative bonds that are within 0.03 Å to their M(Sal) Ph counterpart under the same computational parameters (Table S1 †). In addition, the singly occupied molecular orbitals (SOMO) of Cu(Sal) Fc consist predominantly of a d x 2 -y 2 orbital with spin covalency with the coordinating atoms, which is expected for a square planar, d 9 , Cu II complex (Fig.…”

“…Schiff base 1 was synthesized based on a previous report. 51 The tris(2,4-dibromophenyl)aminium hex-auoroantimonate oxidant (N(C 6 H 3 Br 2 ) 3 SbF 6 , E 1/2 = 1.14 V vs. Fc/Fc + in MeCN) 52,53 was prepared from commercially available triphenylamine by reported procedures. N) were performed at the University of British Columbia on a Thermo Flash 2000 elemental analyzer.…”

“…First, a diaza-Cope rearrangement reaction between (1R,2R)-1,2-bis(2-hydroxyphenyl)-1,2-diaminoethane and 2.2 equivalents of ferrocenecarboxaldehyde yields Schiff-base 1. 51 While 1 is a ferrocenecontaining Sal ligand, the lack of ortho-and para-substituents relative to the phenol oxygen is envisaged to produce less stable oxidized products, as unsubstituted M(Sal) complexes are known to undergo decomposition via oxidative radical polymerization at these positions. [55][56][57][58][59] As such, 1 was hydrolyzed under acidic conditions, then condensed with 2 equivalents of 3,5-di-tert-butylsalicylaldehyde in the presence of an excess of NEt 3 to afford the target ligand H 2 (Sal) Fc .…”

“…49,50 However their incorporation into the secondary coordination sphere of Sal via the sp 3 -carbon of the diamine linker have been far less explored. 51 Furthermore, the electronic spectroscopy and electrochemical behaviors of these compounds have yet to be reported. To this end, this paper will describe the synthesis, spectroscopic characterization and electrochemical studies of a Ni II and Cu II complexes of a novel Sal ligand scaffold in which two ferrocene moieties are incorporated into its secondary coordination sphere via its diimine linker (Chart 1).…”