Stabilisation of high oxidation states by strong electron donors: the crystal structure of tetra-n-butylammonium o-phenylenebisbiuretatocuprate(III)–chloroform

Abstract

The X-ray crystal structure of Buⁿ₄N[Cu-o-C₆H₄(NCONHCONH)₂].CHCl₃ shows that the Cu atom is formally tervalent and is co-ordinated by four deprotonated amide nitrogen atoms; the Cu^III–N bonds (1·82–1·89 Å) are shorter than those found in related Cu^II complexes.