trans-Tetraamminebis(hydrogensulfito)ruthenium(II), trans-[Ru(SO3H)2(NH3)4], a Structure with an Unexpected Rod Packing

Abstract

trans-[Ru(SO3H)2(NH3)4], monoclinic, space group P21/n, Z =2, a = 619.4(3), b = 701.8(3), c = 1068.6(6) pm, β = 96.32(3)°. In the centrosymmetric octahedral complex the two independent Ru–N bonds are equal within experimental error (average Ru–N 214.0 pm). The rather short Ru–S bonds (227.6 pm) indicate a very weak trans-influence of the – SO3H ligand. Caused by the protonation, one of the S–O bonds in the –SO3H ligand is long (161.4 pm), the other two are short (mean 148.0 pm). The complex units are linked by pairs of O-H ··· O hydrogen bonds (268.9 pm) to form rods parallel b (symmetry (b) · T), which in turn are held together by N–H ··· O bonds in a pseudo-hexagonal array. A packing coefficient of 0.76 is estimated.