A novel hybrid terpyridine–pyrimidine ligand and the supramolecular structures of two of its complexes with Zn(II) and acetylacetonato: The underlying role of non-covalent π⋯π contacts and C–H⋯X(O, N, π) hydrogen bonds

A binuclear iron(III) Schiff base complex doubly bridged by hydroxyl groups: Synthesis, structure, and characterization

“…Hydrogen bond lengths and bond angles for complex I are listed in Table 3 for details. These 1D chains are further connected through the C-H … O bonds (C … O 3.511 Å) weak interaction, [16][17][18], which is between the C atoms of 5 nitrosalicylalde hyde and the oxygen atoms of uncoordinated waters, as well as the O-H … O bonds (O … O 3.049 Å) between (1) the O atoms of 5 nitrosalicylaldehyde and the oxygen atoms of uncoordinated waters. It gives rise to the 2D supramolecular architecture as displayed in Fig.…”

“…For C 17 Corrections for Lp factors were applied and all non hydrogen atoms were refined with anisotropic thermal parameters. The structure was solved by direct meth ods with SHELXS 97 [13].…”

4,2’:6’,4”- and 3,2’:6’,3”-Terpyridines: The Conflict between Well-Defined Vectorial Properties and Serendipity in the Assembly of 1D-, 2D- and 3D-Architectures

“…There are a few examples of 4,2’:6’,4”-tpy ligands acting in a monodentate mode [3,4,5,6,7] but, typically, 4,2’:6’,4”-tpy coordinates through the two outer nitrogen atoms, with the central nitrogen atom non-coordinated. Therefore, ligands based upon a 4,2’:6’,4”-tpy metal-binding domain present moderately rigid, well-defined V-shaped motifs (Scheme 1a) which are ideal linkers in coordination assemblies.…”

“…Ligand 6 (Scheme 3) contains a 2-methylpyrimidin-5-yl substituent and we were interested to see if this would be an additional metal-binding domain to cobalt(II). We have previously reported that the pyrimidinyl units in 4’-(pyrimidin-5-yl)-4,2’:6’,4”-terpyridine or 6 remain uncoordinated in reactions with zinc(II) halides [23], whereas Grafino et al observe examples of both coordinated and non-coordinated pyrimidinyl N -donors in reactions of 4’-(4-(pyrimidin-5-yl)phenyl)- 4,2’:6’,4”-terpyridine with Zn(acac) 2 [5]. Ligand 7 (Scheme 3) is related to ditopic ligand 1 (Scheme 2) but offers only one 4,2’:6’,4”-tpy domain.…”

4′-(Pyrimidin-5-yl)- and 4′-(2-methylpyrimidin-5-yl)-4,2′:6′,4″-terpyridines: Selective coordination to zinc(II) through the 4,2′:6′,4″-terpyridine domain

“…2H 2 O results in the assembly of a 2-dimensional network with copper(II) centres coordinated to the pyrimidinyl N-donors [13]. Recently, Granifo et al [14] have reported the synthesis of ligand 2 and shown that it reacts with Zn(acac) 2 (Hacac = acetylacetone) to give the discrete complex [Zn(acac) 2 (2) 2 ], in addition to the 1-dimensional coordination polymer [{Zn(acac) 2 (2)} n ].…”