1,1'-BIS(DIPHENYLPHOSPHINO)FERROCENE (DPPF) COMPLEXES OF GOLD(I) AND GOLD(III) - CRYSTAL-STRUCTURES OF [(DPPF)AUPPH(3)]CLO4-CENTER-DOT-CHCL3 AND [(DPPF)AU(MU-DPPF)AU(DPPF)](CLO4)(2)CENTER-DOT-2CH(2)CL(2)

Displacement of tetrahydrothiophene in gold(I) complexes such as [AuX(tht)] or [Au(tht)L]ClO4 by the 1,1'-bis(diphenylphosphino)ferrocene ligand leads to the neutral [(dppf)(AuX)(2)] [X = C(6)F5 (1), Cl (2)] or cationic dinuclear complexes [(dppf)(AuL)(2)](ClO4)(2) [L = CH(2)PPh(3)(3), CH(2)PPh(2)Me(4), CH(2)PPhMe(2) (5)]. Other dinuclear complexes have been prepare;l by substitution reactions of compound 2, namely [(dppf)(AuL)(2)](n+) [L = SCN, n = 0 (6); L = tht, n = 2 (7)]. Three- and four-coordinated derivatives of the types [(dppf)AuCl] (8), [(dppf)(AuPR(3))]ClO4[PR(3) = PPh(3) (9), PPh(2)Me (10)], [Au(dppf)(2)]ClO4 (11), and [(dppf)Au(mu-dppf)Au(dppF)] (ClO4)(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)]ClO4 affords a mixture of the dinuclear linear complexes [Au(dppf)](2)(ClO4)(2) (13) and the mononuclear three-coordinated complex [(dppf)Autht]ClO4 (14). Similarly, by displacement of tht in [AuR(3)tht] or [AuR(2)(tht)(2)]ClO4 (R = C6F5) by the dppf ligand, the gold(III) derivatives [(dppf)AuR(3)] (15), [(dppf)(AuR(3))(2)] (16), and [(dppf)AuR(2)]ClO4 (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)(AuPPh(3))]ClO4 (9) crystallizes in space group P2(1)/c, monoclinic, with a = 14.239(6) Angstrom, b = 16.889(4) Angstrom, c = 20.866(8) Angstrom, beta = 95.81(3)degrees, and Z = 4. [(dppf)Au(mu-dppf)Au(dppf)]-(ClO4)(2) (12) crystallizes in space group C2/c, monoclinic, with a = 32.858(6) Angstrom, b = 14.821(3) Angstrom, c - 26.399(5) Angstrom, beta = 128.48(2)degrees, 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 degrees.