Copper(I) Complexes derived from Mono- and Diphosphino-Boranes: Cu→B Interactions Supported by Arene Coordination

The monophosphino-boranes o-iPr(2)P(C6H4)BR2 (1 R = Ph and 3: R = Cy) and diphosphino-boranes [o-R2P(C6H4)](2)BPh (5: R = Ph and 6(.)R = iPr) readily react with CuCl to afford the corresponding complexes {[o-iPr(2)P(C6H4)BPh2]Cu(mu-Cl)}(2) 2, {[o-rPr(2)P(C6H4)BCy2]Cu(mu-Cl)}(2)4, {[o-Ph2P(C6H4)](2)BPh}CuCl 7, and {[o-Pr2P(C6H4)](2)BPh} CuCl 8. The presence of Cu -> B interactions supported by arene coordination within complexes 2, 7, and 8 has been unambiguously evidenced by NMR spectroscopy and X-ray diffraction studies. The unique eta(2)-BC coordination mode adopted by complexes 7 and 8 has been thoroughly analyzed by density-functional theory (DFT) calculations