Activation of P4 by U(η5-C5Me5)(η8-C8H6(SiiPr3)2-1,4)(THF); the X-ray structure of [U(η5-C5Me5)(η8-C8H6(SiiPr3)2-1,4)]2(μ-η2:η2-P4)

Abstract

The uranium(III) mixed sandwich complex [U(η⁵-C₅Me₅)(η⁸-C₈H₆(SiⁱPr₃)₂-1,4)(THF)] reacts with white phosphorus to afford dimeric [U(η⁵-C₅Me₄H)(η⁸-C₈H₆(SiⁱPr₃)₂-1,4)]₂(μ-η²:η²⁻P₄), whose X-ray structure reveals a novel η²,η²bonding mode for the bridging P₄ unit. DFT computational studies confirm that the P₄ ring is doubly reduced and show interaction of the uranium atoms with both a σ and a π orbital of the P₄ ring.