Mixed pseudohalide complexes of copper(II). Crystal and molecular structure of [Cu(N3)(NCS)(tmen)] n and of [Cu(N3)(NCO)(tmen)]2 (tmen = N,N,N′,N′-tetramethylethylenediamine)

Abstract

The compounds [Cu(N 3 )(NSC)(tmen)] n (1), [Cu(N 3 )(NCO)(tmen)] n (2) and [Cu(N 3 )(NCO)(tmen)] 2 (3) (tmen ¼ N,N,N¢,N¢-tetramethylethylenediamine) were synthesized and studied by i.r. spectroscopy. Single crystals of compounds (1) and (3) were obtained and characterized by X-ray diffraction. The structure of compound (1) consists of neutral chains of copper(II) ions bridged by a single azido ligand showing the asymmetric end-to-end coordination fashion. Each copper ion is also surrounded by the other three nitrogen atoms; two from one N,N,N¢,N¢-tetramethylethylenediamine and one from a terminal bonded thiocyanate group. Compound (2) decomposes slowly in acetone and the product formed [Cu(N 3 )(NCO)(tmen)] 2 (3) crystallizes in the monoclinic system (P2 1 ). The structure of (3) consists of dimeric units in which the Cu atoms are penta-coordinated and connected by l(1,3) bridging azido and cyanate ligands. In both cases the five coordinated atoms give rise to a slightly distorted square-based pyramid coordination geometry at each copper ion. The thermal behavior of [Cu(N 3 )(NSC)(tmen)] n (1) and [Cu(N 3 )(NCO)(tmen)] n (2) were investigated and the final decomposition products were identified by X-ray powder diagrams.

Synthesis, crystal structures, and urease inhibitory activities of two azido-bridged polynuclear copper(II) complexes with Schiff bases

“…Metal-organic complexes containing bridging ligands are of great interest for their versatile molecular topologies and specific functionalities [1][2][3]. Due to the versatile coordination modes of the ambidentate azido ligand, this pseudohalide has become one of the most extensively studied building blocks in the synthesis of polynuclear complexes [4,5].…”

Synthesis, crystal structures, and antimicrobial activity of a pair of isostructural dinuclear copper(II) complexes derived from 4-nitro-2-[(2-diethylaminoethylimino)methyl]phenol

“…The azide and thiocyanate anions are versatile bridging ligands, which are able to link metal ions with different coordination modes, generating a wide variety of polynuclear complexes with interesting structures [15][16][17][18]. The most common bridging coordination mode of the azide and thiocyanate ligands are end-on (EO) and end-to-end (EE).…”

A 2D coordination polymer with brick-wall network topology based on the [Cu(NCS)2(pn)] monomer

“…The four nitrogen atoms and the copper ion are rigorously over a symmetry plane m. The Cu-N(3) and Cu-N(4) bond lengths of 2.005(4) and 2.006(6) Å , respectively, agree well with the values found for [Cu 2 (N 3 ) 4 (pn) 2 ] (2.000 Å ) [7] but are slightly shorter than those reported for [Cu(NO 3 ) 2 (pn) 2 ] (2.023 Å ) and [Cu(N 3 )(NO 3 )(pn) 2 ] (2.031 Å ) [8]. There is a slight difference among the Cu-N(1) and Cu-N(2) of 1.997(6) and 1.973(4) Å bond distances for 1, and those found for [Cu(N 3 )(NCS)(tmen)] n (tmen = N,N,N 0 ,N 0 -tetramethylethylenediamine) (1.960(3) Å ) [9]. The thiocyanato ions are essentially linear with N(1)-C(1)-S(1) and N(2)-C(2)-S(2) angles equal to 178.8(5) and 179.3(6)°, respectively.…”