1,1'-Bis(diphenylphosphino)ferrocene (dppf) complexes of gold(I) and gold(III). Crystal structures of [(dppf)AuPPh3]ClO4.cntdot.CHCl3 and [(dppf)Au(.mu.-dppf)Au(dppf)](ClO4)2.cntdot.2CH2Cl2

Displacement of tetrahydrothiophene in gold(I) complexes such as [AuX(tht)] or [Au(tht)L]C104 by the 1,Vbis(diphenylphosphino)ferrocene ligand leads to the neutral [(dppf)(AuX)2] [X = C6F5 (1), Cl (2)] or cationic dinuclearcomplexes[(dppf)(AuL)2](C104)2[L = CH2PPh3(3),CH2PPh2Me(4),CH2PPhMe2(5)]. Other dinuclear complexes have been prepared by substitution reactions of compound 2, namely [(dppf)(AuL)2j',+ [L = SCN, = 0 (6); L =tht, = 2 (7)]. Three- and four-coordinated derivatives of the types [(dppf)AuCl] (8), [(dppf)- (AuPR3)]C104[PR3 = PPh3 (9), PPh2Me (10)], [Au(dppf)2]C104 (11), and [(dppf)Au^-dppf)Au(dppf)](C104)2 (12) are obtained by reaction of the gold(I) precursor and the diphosphine. The reaction of equimolecular amounts of dppf and [Au(tht)2]C104 affords a mixture of the dinuclear linear complexes [Au(dppf)]2(C104)2 (13) and the mononuclear three-coordinated complex [(dppf)Autht]C104 (14). Similarly, by displacement of tht in [AuR3tht] or [AuR2(tht)2]C104 (R = C6F5) by the dppf ligand, the gold(III) derivatives [(dppf)AuR3] (15), [(dppf)(AuR3)2j (16), and [(dppf)AuR2]C104 (17) can be synthesized. Cyclic voltammetry of some of the compounds reveals one chemically reversible phosphinoferrocene-based oxidation. Single-crystal X-ray structure determinations were performed for complexes 9 and 12. [(dppf)(AuPPh3)]C104 (9) crystallizes in space group P2\/c, monoclinic, with a = 14.239(6) A, b = 16.889(4) A, c = 20.866(8) A, ß = 95.81(3)°, and Z = 4. [(dppf)Au(g-dppf)Au(dppf)]-(C104)2 (12) crystallizes in space group C2/c, monoclinic, with a = 32.858(6) A, b = 14.821(3) A, c = 26.399(5) Á, ß - 128.48(2)°, and Z = 4. The cation of 12 is exactly centrosymmetric. Both complexes show trigonal planar coordination at gold. The ferrocene rings are staggered by 18-36°.