Crystal structures and solution dynamics of mono- and di-nuclear rhodium complexes of heterodinucleating macrocyclic ligands containing the 2,6-di(thiomethyl)pyridine sub-unit

Abstract

Rhodium complexes of four macrocyclic ligands in which a polyether chain links a 2,6-di(thiomethyl)pyridine sub-unit are reported. The rhodium(I) carbonyl complex of 6,9,12-trioxa-3,15-dithia-21 -azabicyclo[l5.3.1]heneicosa-1(21),17,19-triene is dimeric with a weak metal-metal interaction [Rh–Rh 3.332 O(6)Å] and in the rhodium(III)–dichloro complex with 6,9,12,15,18-pentaoxa-3,21 -dithia-27-azabicyclo[21.3.1]heptacosa-1 (27),23,25-triene a water molecule is bound to the metal and is hydrogen bonded to two of the oxygens of the polyether chain. Dinuclear complexes with bridging and terminal carbonyl ligands are formed with 6-oxa-3,9-dithia-15-azabicyclo[9.3.1]pentadeca-1 (15),11,13-triene and its dimer 6,20-dioxa-3,9,17,23-tetrathia-29,30-diazatricyclo[23.3.1.1 ^11,15]triaconta-1 (29),11,13,15(30),25,27-hexaene respectively.