HALF-SANDWICH RUTHENIUM PHOSPHINE COMPLEXES WITH SULFUR-DONOR LIGANDS- X-RAY CRYSTAL-STRUCTURES OF [CP-ASTERISK-RUH(SH)(PET3)(2)][BPH4] AND [CP-ASTERISK-RU((S2COPR)-PR-I)(PET3)]

The complexes [CpRuCl(PEt3)(2)] (1) and [CpRuCl((PMePr2)-Pr-i)(PPh3)] (2) react with H2S in EtOH in the presence of NaBPh4 furnishing the gr een persulfide derivatives [{CpRu(L)}(2)(mu-S-2)][BPh4](2) (L = (PEt3) (2), ((PMePr2)-Pr-i)(PPh3)), which were also obtained by reaction of 1 or 2 with elemental sulfur and NaBPh4 in MeOH. At variance with this, the reaction of [CpRuCl(PEt3)(2)] (3) with H2S in EtOH afforded the Ru-IV hydrido-metallothiol [CpRuH(SH)(PEt3)(2)][BPh4], which has been structurally characterized, derived from the oxidative addition of SH 2 to the electron-rich Ru-II moiety {[CpRu(PEt3)(2)](+)}. This compou nd is oxidized to yield the persulfide complex [{CpRu(PEt3)(2)}(2)(mu -S-2)][BPh4](2), which was also obtained by reaction of 3 with element al sulfur. The reaction of 1, 2, and 3 with 2-mercapto-pyridine (HSPy) in EtOH yielded cationic complexes in which HSPy is tautomerized to i ts 1H-pyridine-thione form as inferred from spectral data. Compound 1 reacts with potassium alkyl-xanthates KS2COR (R = Me, Et, Pr-i) yieldi ng compounds of the type [CpRu(eta(1)-S2COR)(PEt3)(2)], whereas the re action of 2 and 3 led respectively to the complexes [CpRu(eta(2)-S2COR )((PMePr2)-Pr-i)] and [CpRu(eta(2)-S2COR)(PEt3)], which contain one b identate xanthate and one phosphine. The X-ray crystal structure of [C pRu((S2COPr)-Pr-i)(PEt3)] was determined. In analogous fashion, the r eaction of 1 with sodium diethyldithiocarbamate yielded [CpRu(eta(1)-S 2CNEt2)(PEt3)(2)], whereas 2 and 3 afforded the corresponding derivati ves [CpRu(eta(2)-S2CNEt2)((PMePr2)-Pr-i)] and [CpRu(eta(2)-S2CNEt2)(P Et3)].