Synthesis and Characterization of [3]Ferrocenophane-derived P, P-Chelate Ligand Gold Complexes Featuring an Aurophilic Interaction

Abstract

The P,P-chelate ligand (rac)-4 was prepared starting from the α-dimethylamino-[3]ferrocenophane by a series of directed ortho-lithiation, phosphination with ClPPh2 and substituent exchange using HPiPr2. Treatment with two molar equivalents of (Me2S)AuCl subsequently gave the corresponding κP,κP(AuCl)2 complex (rac)-9. In similar sequences the α-PCy2/o-PPh2 ligands (S,S,Spl )- 2 and the "substituent-invertomer" (R,R,Rpl)-3 (α-PPh2/o-PCy2) were prepared. Treatment with (Me2S)AuCl in a 1 : 2 ratio gave the chelate ligand-(AuCl)2 complexes (S,S,Spl )-8 and (R,R,Rpl)- 11, respectively. The ligand (rac)-4 and the gold complexes 8, 9 and 11 were characterized by X-ray diffraction. All three show an intramolecular Au . . . Au interaction