Flexible Bonding of the Phosph(V)azane Dianions [S(E)P(μ‐NtBu)]22−

Abstract

Oxidation of the PIII dianion [S−P(μ‐NtBu)]22− (1) with elemental sulphur, selenium and tellurium gives the PV dianions [(S)(E)P(μ‐NtBu)]22− (E = S (6 a), Se (6 b), Te (6 c)). Although 6 c proves to be too unstable, the S,S‐dianion 6 a and ambidentate S,Se‐dianion 6 b are readily transferred intact to main group and transition metal elements, producing a range of new cage and coordination compounds. While their coordination characteristics are in many ways similar to closely‐related isoelectronic phosph(V)azane anions [(E)(RN=)P(μ‐NtBu)]22−, the sterically unhindered nature of 6 introduces an expanded range of coordination modes, that is, facial S,S‐ and Se,Se‐bonding as well as side‐on S,Se‐coordination. All of these bonding modes are observed for the amibidentate S,Se dianion 6 b.