2,6-Dipicolinoylbis(N,N-dialkylthioureas) as versatile building blocks for oligo- and polynuclear architectures

Abstract

Similar reactions of 2,6-dipicolinoylbis(N,N-diethylthiourea) (H₂L^a) with: (i) Ni(NO₃)₂·6H₂O, (ii) a mixture of Ni(NO₃)₂·6H₂O and AgNO₃, (iii) a mixture of Ni(OAc)₂·4H₂O and PrCl₃·7H₂O and (iv) a mixture of Ni(OAc)₂·4H₂O and BaCl₂·2H₂O give the binuclear complex [Ni₂(L^a)₂(MeOH)(H₂O)], the polymeric compound [NiAg₂(L^a)₂]_∞, and the heterobimetallic complexes [Ni₂Pr(L^a)₂(OAc)₃] and [Ni₂Ba(L^a)₃], respectively. The obtained assemblies can be used for the build up of supramolecular polymers by means of weak and medium intermolecular interactions. Two prototype examples of such compounds, which are derived from the trinuclear complexes of the types [M^II₂Ln^III(L)₂(OAc)₃] and [M^II₂Ba(L)₃], are described with the compounds {[Cu^II₂Dy^III(L^a)₂(p-O₂C-C₆H₄-CO₂)(MeOH)₄]Cl}_∞ and [Mn^II₂Ba(MeOH)(L^b)₃]_∞, H₂L^b = 2,6-dipicolinoylbis(N,N-morpholinoylthiourea).