Copper(I) azide and copper(I) cyanate π-complexes

Abstract

Electrochemical alternating current synthesis starting from an ethanol solution of CuSO4 · 5H2O and allylamine in the presence of solid sodium azide results in formation of Cu[C3H5NH2]N3. The trigonal-pyramidal coordination environment of both crystallographically independent copper ions consists of the C = C-bond of one allylamine molecule, the NH2-group of another ligand moiety and two N-atoms of the two azide-anions. One N3 − exhibits a terminal coordination mode and the other is a μ3-1,1,3-bridge. The bridging function of both allylamine and azide leads to formation of a complicated 3-D network. An elongation of coordinated C = C-bond and a strong shift of the ν s mode in the Raman spectrum confirm effective Cu–(C = C) bonding. A similar synthetic route starting from a methanol solution of Cu(BF4)2 · 6H2O in the presence of solid potassium cyanate results in formation of Cu[C3H5NH2]NCO. The cyanate-anion is bound to copper through nitrogen. The nitrogen from the allylamine molecule and the C = C-bond from another ligand complete the trigonal-planar environment of copper. The elongation of the coordinated C = C-bond and the shift of ν s (C = C) mode in the Raman spectrum are similar to those in the azide derivative.