title: PPh3-derivatives of [Pt3n(CO)6n]2- (n = 2-6) Chini's clusters: syntheses, structures, and 31P NMR studies.
abstract: The reaction of the [Pt3n(CO)6n](2-) (n = 2-6) Chini's clusters with increasing amounts of PPh3 has been investigated in detail by combined FT-IR, (31)P{(1)H} NMR, and electrospray ionization-mass spectrometry (ESI-MS) studies, showing that up to three CO ligands are gradually substituted by PPh3, resulting in isonuclear phosphine-substituted anionic clusters of general formula [Pt3n(CO)(6n-x)(PPh3)(x)](2-) (n = 2-6; x = 1-3). Further addition of PPh3 results in the elimination of the neutral Pt3(CO)3(PPh3)3 species and formation of lower nuclearity anionic clusters. [Pt12(CO)22(PPh3)2](2-) and [Pt9(CO)16(PPh3)2](2-) have been structurally characterized, and they maintain the trigonal prismatic structures of the parent homoleptic clusters, with the two PPh3 ligands bonded to different external Pt3-triangles in relative cis-position. Conversely, the crystal structure of [Pt6(CO)10(PPh3)2](2-) shows that its metal cage is transformed from trigonal prismatic to trigonal antiprismatic after CO/PPh3 exchange.
authors.affiliation: Dipartimento di Chimica Industriale Toso Montanari, Università di Bologna, Viale Risorgimento 4-40136 Bologna, Italy.
authors.forename: Iacopo
authors.initials: I
authors.lastname: Ciabatti
authors.forename: Cristina
authors.initials: C
authors.lastname: Femoni
authors.forename: Maria Carmela
authors.initials: MC
authors.lastname: Iapalucci
authors.forename: Giuliano
authors.initials: G
authors.lastname: Longoni
authors.forename: Tatiana
authors.initials: T
authors.lastname: Lovato
authors.forename: Stefano
authors.initials: S
authors.lastname: Zacchini