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]
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.