Vanadium(V) Complexes of 2,2‘-Thiobis(4-methyl-6-<i>tert</i>-butylphenol) (H₂mbp₂S) and 2,2‘-Sulfinylbis(4-methyl-6-<i>tert</i>-butylphenol) (H₂mbp₂SO)

Abstract

The sulfide-containing ligand 2,2‘-thiobis(4-methyl-6- tert -butylphenol), H 2 mbp 2 S, coordinates facially to vanadium forming six-coordinate alkoxide- ( 1 ) or hydroxide-bridged ( 2 ) dimers that have been structurally characterized. 51 V NMR indicates that structural isomers are present. Electrochemical studies indicate that the metal centers in 1 are strongly coupled ( K com ≈ 10 5 ). The corresponding sulfoxide, H 2 mbp 2 SO, coordinates to vanadium(V) to form a six-coordinate complex with a 2:1 L:M stoichiometry. Under the conditions of this study, direct oxygenation of the coordinated sulfide in 1 and 2 has not been observed. Crystal data for 1 (C 55 H 74 O 8 S 2 V 2 ): space group R -3, a = 35.6184(2) Å, b = 35.6184(2) Å, c = 13.52170(10) Å, α, β = 90°, γ = 120°, Z = 18. Crystal data for 2 (C 26 H 35 N 2 O 4 SV): space group P 2(1)/ n, a = 13.2894(2) Å, b = 12.9652(2) Å, c = 16.3639(2) Å, α,γ = 90°, β = 102.43°, Z = 4. Crystal data for 3 (C 50 H 70 O 7 S 2 V): space group P -1, a = 9.1567(5) Å, b = 13.9314(8) Å, c = 19.7196(11) Å, α = 79.1460(10)°, β = 86.5840(10)°, γ = 82.7570(10)°, Z = 2.