Synthesis and nuclear magnetic resonance study of the auranonaborane and diauradecaborane arachno-type compounds, [4-(S2CNEt2)-arachno-4-AuB8H12] and [6,9-(S2CNEt2)2-arachno-6,9-Au2B8H10]; crystal and molecular structure of [6,9-(S2CNEt2)2-arachno-6,9-Au2B8H10]

Abstract

The reaction of [AuBr₂(S₂CNEt₂)] with the arachno-[B₉H₁₄]^– anion gives the very pale yellow arachno nine-vertex compound [4-(S₂CNEt₂)-4-AuB₈H₁₂](1) and the bright yellow arachno 10-vertex compound [6,9-(S₂CNEt₂)₂-6,9-Au₂B₈H₁₀](2) in low yield. Both compounds are characterized by multi element single- and double-resonance n.m.r. spectroscopy, and compound (2), also by single-crystal X-ray diffraction analysis. The metal-to-borane bonding mode is similar to that in the iridium and platinum species [1-Cl-4,4,4,4-(PMe₃)₂(CO)H-4-IrB₈H₁₁] and [4,4-(PMe₂Ph)₂-4-PtB₈H₁₂], to which it is compared.