Phosphine-gold(I) derivatives of 1,1'-bis(alkynyl)metallocenes: Molecular structures of Fc (C=CX)2[X = Au(PPh3), SiMe3] and Au4{(CC)2Fc }2(PPh3)2 [Fc = Fe(?-C5H4-)2]

Desilylation of Fc'(CCSiMe3)2 [1; Fc' = Fe(η-C5H4-)2] with LiMe or KOH/MeOH, followed by addition of AuCl(PR3), afforded Fc'{CCAu(PR3)}2 [R = Ph 2a, tol 2b]; the Ru analogue of 2a was also prepared. The XRD structures of 1 and 2a are reported. In the presence of CuI, a similar reaction over 2 h afforded the Au4 cluster Au 4{(CC)2Fc'}2(PPh3)2 3. The X-ray determined structure of 3 showed a planar centrosymmetric Au 4 rhomb, two opposed Au atoms being σ-bonded to the CC group, while the other two Au atoms are each η2-bonded to the CC group and a PPh3 ligand. The novel cluster complex Au4{(CC) 2Fc'}2(PPh3)2 3 has been obtained by desilylation of Fc'(CCSiMe3)2 [Fc' = Fe(η-C 5H4-)2] with LiMe or KOH/MeOH, followed by addition of AuCl(PR3) in the presence of CuI. © 2010 Elsevier B.V. All rights reserved.Michael I. Bruce, Martyn Jevric, Brian W. Skelton, Allan H. White and Natasha N. Zaitsev