Bimetallic Complexes of Group 8, 9, and 11 Metals Bridged by RB(NCH₂PPh₂)₂C₆H₄ (R = H, 4-C₆H₄X; X = H, Me, F) Ligands

Abstract

The 1‐aryl‐2,1,3‐diazaboroles ArB(NCH2PPh2)2C6H4 (Ar = C6H5 1a, 4‐MeC6H4 1b, 4‐FC6H4 1c) result from the reactions of ArBCl2 with 1,2‐(NHCH2PPh2)2C6H4 in the presence of triethylamine. The reactions of these new proligands in addition to the parent diazaborole HB(NCH2PPh2)2C6H4 (4) with a range of metal precursors [Ru2(µ‐Cl)2Cl2(η6‐1,3,5‐Me3C6H3)2], [M2(µ‐Cl)2Cl2(η5‐C5Me5)2], [M2(µ‐Cl)2(η4‐C8H12)2] (M = Rh, Ir) and [AuCl(SC4H8)] have been explored. Rather than forming chelating, bidentate mono‐metallic complexes, these ligands are found to support the formation of bimetallic complexes without any indication of B–C activation (oxidative addition, transmetallation etc.). In the presence of excess 1a–b, iridium is found to form ligand bridged coordination polymers.