New Group 2 metal hydrazinecarboxylates: a novel co-ordination mode for hydrazinecarboxylate in a polymeric, ten-co-ordinate barium complex

Abstract

The new hydrazinecarboxylates [M(O₂CNHNH₂)₂](M = Mg or Sr) and [Ba(O₂CNHNH₂)₂(N₂H₄)] have been prepared. The barium compound is polymeric, each barium centre being ten-co-ordinate and the hydrazinecarboxylate anions displaying a novel co-ordination mode. Each anion is O,O′-chelating to one barium, O-bridging to a second and bonded to a third barium via the terminal nitrogen of the hydrazino moiety. The first two barium cations are also connected by a N,N′-bridging hydrazine ligand and the lattice arrangement is cemented by a series of hydrogen bonds.