Reactions of hydrazine ligands. Part I. Synthesis and X-ray structure determination of a nickel(II) complex of a novel monoanionic macrocyclic ligand

Abstract

Reactions of 1,3-bis(2-hydrazinophenylthio)propane (2) with formaldehyde in the presence of nickel(II) salts are reported, the first of a study of metal-ion template control of condensation reactions of aromatic hydrazines. Complexes of an unusual macrocyclic ligand result, in which the two hydrazine groups have been ‘bridged’ by the carbon atom of formaldehyde, and spontaneous aerial oxidation gives a novel monoanionic chelate ring containing four nitrogen atoms, (16,17-Dihydro-15H-dibenzo[f,m][1,11,4,5,7,8]dithiatetra-azacyclotetradecinato-N⁵,N⁹,S¹⁴,S¹⁸)-nickel(II) perchlorate (9) in an unsolvated monoclinic form, space group P2₁/c with a= 13.646(4), b= 9.374(3), c= 16.674(4)Å, γ= 96.02(4)°, and Z= 4, allowed a more satisfactory X-ray structure determination (heavy-atom method, 2 299 diffractometer data, R 7.7%) than the triclinic methanol salvate previously examined.

The complex shows planar co-ordination geometry with the conjugated anionic chelate ring lying close to this plane. The perchlorate counter ion is well separated from the nickel ion in both crystalline modifications [shortest Ni ⋯ O contacts 3.51(2) and 3.51(6)Å].