Complexes of rhenium and osmium with o-phenylenediamine and o-aminobenzenethiol. X-Ray crystal structures of [Re{o-(HN)2C6H4}3][ReO4], Re[o-(HN)2C6H4]3, Re[o-(HN)2C6H4]2[o-(HN)NC6H4], K[Re{o-(HN)2C6H4}-{o-(HN)NC6H4}2], and M[o-(HN)SC6H4]3(M = Re or Os)

Abstract

The interaction of trimethylsilyl perrhenate, ReO₃(OSiMe₃), or Re₂O₇, with o-phenylenediamine gives the homoleptic amido complex cation of rhenium(VII), [Re{o-(HN)₂C₆H₄}₃]⁺, as its perrhenate salt. The cation can be reduced by sodium to the neutral rhenium(VI) species Re[o-(HN)₂C₆H₄]_3′ which can be reoxidised by AgPF₆ to the cation as its hexafluorophosphate salt. Interaction of [Re{o-(HN)₂C₆H₄}₃]⁺ with KOH leads to the singly and doubly deprotonated species, Re[o-(HN)₂C₆H₄]₂[o-(HN)NC₆H₄] and K[Re{o-(HN)₂C₆H₄}{o-(HN)NC₆H₄}₂]. An improved preparation of the known amido thiolate Re[(HN)SC₆H₄]_3′i.e. interaction of o-(H₂N)(HS)C₆H₄ with ReO₃-(OSiMe₃), is described; the osmium analogue, Os[(HN)SC₆H₄]_3′ is synthesised by interaction of the aminothiol with OsO₄. Interaction of OsO₄ with o-(H₂N)₂C₆H₄ gives the complex trans-OsO₂[(HN)₂C₆H₄]₂. Infrared, ¹H n.m.r., e.s.r., and electronic absorption and cyclic voltammetric data are given. The X-ray crystal structure of the cation [Re{o-(HN)₂C₆H₄}₃]⁺ as the acetone solvate of the perrhenate shows a trigonal prismatic geometry, which is also confirmed for Re[o-(HN)₂C₆H₄]₃, Re[o-(HN)₂C₆H₄][o-(HN)NC₆H₄], K[Re{o-(HN)₂C₆H₄}{o-(HN)NC₆H₄}₂], and Re[(HN)SC₆H₄]₃. The structure of Os[o-(HN)SC₆H₄]₃ shows it to have a slightly distorted octahedral geometry.