Di-mu-cyanato-bis[(cyanato-kappaN)(tetramethylethylenediamine-kappa2N,N')copper(II)] and catena-poly[[mu3-cyanato-kappa3O:N:N-bis[(cyanato-kappaN)(1,3-diaminopropane-kappa2N,N')copper(II)]]-mu3-cyanato-kappa3N:N:O

Abstract

The two title Cu(II) complexes, [Cu(2)(NCO)(4)(tmeda)(2)] (tmeda is tetramethylethylenediamine, C(6)H(16)N(2)), (I), and [Cu(NCO)(2)(pn)](n) (pn is 1,3-diaminopropane, C(3)H(10)N(2)), (II), have been synthesized and their crystal structures determined. In (I), which lies about an inversion centre, each Cu centre possesses a distorted tetragonal-pyramidal geometry with four basal N atoms from two cyanate anions [Cu-N = 1.945 (2) and 1.948 (3) A] and one tmeda molecule [Cu-N = 2.053 (2) and 2.071 (2) A], and one axial O atom [Cu-O = 2.737 (3) A] from another cyanate anion. The two neighbouring Cu atoms in (I) are joined by a pair of cyanates in an end-to-end fashion, forming a dimer. In (II), each Cu centre adopts a distorted square-bipyramidal geometry, with four equatorial N atoms from two cyanates [Cu-N = 1.988 (2) and 2.007 (3) A] and a pn ligand [Cu-N = 1.996 (3) and 2.011 (3) A], and one apical N atom [Cu-N = 2.437 (3) A] and an apical O atom [Cu-O = 2.900 (3) A] from two cyanates. In contrast with (I), the two neighbouring Cu atoms in (II) are bridged by two cyanates in an end-on fashion, to form a centrosymmetric dimeric unit. These units are further crosslinked, forming a two-dimensional network structure, via weak interactions between the bridging cyanate O atom and a neighbouring Cu atom, plus interactions of the amine H atoms with the cyanate O atoms and the terminal cyanate N atom.