TY - JOUR
T1 - Sulfido-Persulfido Equilibria in Sulfur-Rich Metal Clusters
T2 - The Case of (C5Me5)3RhRu2S4 2+
AU - Venturelli, Anne
AU - Rauchfuss, Thomas B.
AU - Verma, Atul K.
PY - 1997/3/26
Y1 - 1997/3/26
N2 - The reaction of [(C5Me5)M(MeCN)3](PF6)2 with (C5Me5)2Ru2S4 gives the cluster compounds [(C5Me5)3MRu2S 4(Me-CN)](PF6)2, 1(PF6)2 (M = Rh) and 3(PF6)2 (M = Ir). Crystallographic studies of 1(PF6)2 show that the dication consists of an asymmetric RhRu2S4 core containing an isosceles triangle of metal atoms with a Ru-Ru bond of 2.88 Å. The three metal atoms are joined by two μ3-η1:η2:η1-S 2 units, each persulfide being monodentate toward Rh. NMR studies show that 12+ is stereochemically nonrigid such that the two Ru(C5Me5) resonances coalesce at higher temperatures. The dynamic processes involving 12+ are unaffected by added (C5Me5)Rh(MeCN)32+, ruling out dissociation of the (C5Me5)Rh center. Exchange of the (C5Me5)Ru sites in [(C5Me5)2(C5Me 4Et)-RhRu2S4(MeCN)](PF6) 2, 2(PF6)2, is associated with coalescence of the pairs of C5Me4Et resonances, suggesting that the dynamics in 12+ involve racemization. It is proposed that these dynamics proceed via the "base-free" intermediate [(C5Me5)3RhRu2S4] 2+, wherein one S-S bond has been cleaved. Solutions of 12+ react with acetone to give the S-acetonyl derivative [(C5Me5)3RhRu2S3(SCH 2COCH3)]PF6, 4(PF6). This species, which is not fluxional on the NMR time scale, is a rare example of a metal sulfido cluster with a trigonal prismatic M3S3 core. There is one metal-metal bond of 2.75 Å between the two Ru atoms, spanned by the acetonylthio ligand. The M-S distances are nearly equivalent at 2.33 Å while the S-S bonding distance is 2.12 Å. This reaction is reversed by acid to give 12+ and acetone.
AB - The reaction of [(C5Me5)M(MeCN)3](PF6)2 with (C5Me5)2Ru2S4 gives the cluster compounds [(C5Me5)3MRu2S 4(Me-CN)](PF6)2, 1(PF6)2 (M = Rh) and 3(PF6)2 (M = Ir). Crystallographic studies of 1(PF6)2 show that the dication consists of an asymmetric RhRu2S4 core containing an isosceles triangle of metal atoms with a Ru-Ru bond of 2.88 Å. The three metal atoms are joined by two μ3-η1:η2:η1-S 2 units, each persulfide being monodentate toward Rh. NMR studies show that 12+ is stereochemically nonrigid such that the two Ru(C5Me5) resonances coalesce at higher temperatures. The dynamic processes involving 12+ are unaffected by added (C5Me5)Rh(MeCN)32+, ruling out dissociation of the (C5Me5)Rh center. Exchange of the (C5Me5)Ru sites in [(C5Me5)2(C5Me 4Et)-RhRu2S4(MeCN)](PF6) 2, 2(PF6)2, is associated with coalescence of the pairs of C5Me4Et resonances, suggesting that the dynamics in 12+ involve racemization. It is proposed that these dynamics proceed via the "base-free" intermediate [(C5Me5)3RhRu2S4] 2+, wherein one S-S bond has been cleaved. Solutions of 12+ react with acetone to give the S-acetonyl derivative [(C5Me5)3RhRu2S3(SCH 2COCH3)]PF6, 4(PF6). This species, which is not fluxional on the NMR time scale, is a rare example of a metal sulfido cluster with a trigonal prismatic M3S3 core. There is one metal-metal bond of 2.75 Å between the two Ru atoms, spanned by the acetonylthio ligand. The M-S distances are nearly equivalent at 2.33 Å while the S-S bonding distance is 2.12 Å. This reaction is reversed by acid to give 12+ and acetone.
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U2 - 10.1021/ic9609564
DO - 10.1021/ic9609564
M3 - Article
AN - SCOPUS:0000131612
SN - 0020-1669
VL - 36
SP - 1360
EP - 1365
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 7
ER -