Synthesis and crystal structure of Ru~(III)-supported tungstoantimonate [Sb_2W_20Ru_2~III (H_2O)_2(dmso)_6O_(68)]~(4-)

摘要

The first Ru~(III)-supported tungstoantimonate [Ru~(II)(bpy)_3]_2[Sb_2W_(200Ru_2~(III) (H_2O)_2(dmso)_6O_(680]· 3dmso (bpy = bi-pyridine) (1a) has been successfully isolated as [Ru(bpy)_3]~(2+) (Rubpy) salt by routine synthetic reaction in mixed solutions with dmso and water. Single-crystal X-ray analysis was carried out on 1a, which crystallizes in the triclinic system space group P-1 with a = 16.804 (6), b = 16.988 (6), c = 17.666 (6)A , α = 107.397 (13)°, β = 106.883 (13)°, γ = 103.616 (12)°. V = 4309 (3)A 3, Z = 1 with R1 = 0.0773. The compound 1a reveals the following features: (1) Rubpy is firstly used as an alternative rutheniumsource for the synthesis of Ru-substituted heteropolytungstate; (2) the structure of 1a consists of four RuIII–O–S(CH_3)_2 and two W–O–S(CH_3)_2 bonds resulting in an assembly with C_2 symmetry; (3) the Ru~(III) ions are linked to two dmso groups via two Ru~(III)–O–S(CH_3)_2 bonds, which represents the other dmso-coordination mode to RuIII in POM chemistry. The cyclic voltammetry studies of 1a in dmso/ H_2SO_4 (3/1 v/v) at pH 2.5 medium using the glassy carbon electrode as a working electrode show the respective electrochemical behaviors of the W-centers and the Ru-centers within 1a, which could be separated clearly. In addition, the compound 1a exhibits photoluminescence arising from π*-t_(2g) ligandto- metal transition of Rubpy.