The coordination chemistry of two symmetric fluorene-based organic ligands with cuprous chloride

Abstract

Two novel symmetric fluorene-based ligands, namely, 2,7-bis(1H-imidazol-1-yl)-9,9-dimethyl-9H-fluorene [L1 or (I), C21H18N4] and 2,7-bis(1H-imidazol-1-yl)-9,9-dipropyl-9H-fluorene (L2), have been used to construct the coordination polymers catena-poly[[dichloridodicopper(I)(Cu-Cu)]-μ-2,7-bis(1H-imidazol-1-yl)-9,9-dimethyl-9H-fluorene], [Cu2Cl2(C21H18N4)]n, (II), and catena-poly[[tetra-μ2-chlorido-tetracopper(I)]-bis[μ-2,7-bis(1H-imidazol-1-yl)-9,9-dipropyl-9H-fluorene]], [Cu4Cl4(C25H26N4)2]n, (III). There are three types of C-H···N hydrogen bonds in (I), resulting a two-dimensional network in the ab plane, including a chiral helical chain along the b axis. Compounds (II) and (III) are related one-dimensional polymers. In both, Cu(I) atoms connect the symmetric ligands (L1 or L2) into a one-dimensional chain. In (II), the {[Cu(I)Cl2](-)} unit, acting as a co-anion, adheres to the one-dimensional chain through a weak Cu···Cu interaction. However, in (III), the {[Cu(I)2Cl4](2-)} unit links two different chains into a one-dimensional rope-ladder-type chain. In addition, there are C-H···Cl hydrogen bonds and π-π interactions in the extended structures of (II) and (III), the difference is that the chains in (II) are linked into a two-dimensional network while the chains in (III) are stacked into a three-dimensional framework.

Synthesis and characterization of two novel bimetallic macrocyclic complexes generated from 1,2,4-triazole-containing semi-rigid ligands andM(NO3)2units (M= Ni and Zn)

“…5b). A similar nanotube structure has been reported previously (Dai et al, 2008;Liu et al, 2013). Strong hydrogen bonds involving methanol O atoms, amino N atoms (as donors) and free nitrate N atoms (as acceptors) (O4-H4AÁ Á ÁO14 and N5-H5AÁ Á ÁO13) in the Zn1-containing bimetallic rings lead to the formation of a small zero-dimensional molecular cage (Fig.…”