Synthesis and crystal structures of binuclear complexes of cobalt(II) and cadmium(II) diisobutyldithiophosphinates with hexamethylenetetramine

Heteroligand complexes [Co2(HMTA)(iso-Bu2PS2)4] (I) (μeff = 4.67 μB) and [Cd2(HMTA)(iso-Bu2PS2)4] (II) have been synthesized. Single crystals of compounds I and II have been obtained. The crystals are monoclinic: a = 32.622(2) Å, b = 9.4891(6) Å, c = 21.7570(13) Å, β = 125.774(1)o, V = 5464.3(6) Å,3, Z = 4, ρcalcd = 1.331 g/cm3 for I; a = 34.6092(7) Å, b = 9.5595(2) Å, c = 22.3473(5) Å, β = 127.144(1)o, V = 5893.5(2) Å, Z = 4, ρcalcd = 1.355 g/cm3 for II; space group for both complexes C2/c. Structures I and II are based on discrete binuclear molecules. The coordination polyhedra of the Co and Cd atoms are distorted tetragonal pyramids NS4, with the bases formed by four S atoms of two bidentate chelating ligand iso-Bu2PS 2 − and the axial vertices occupied by N atoms of bidentate bridging HMTA ligand. The character of interaction of the molecules in structures I and II is considered.