Dithiolate complexes of ruthenium and osmium:: X-ray structures of [Ru2(CO)6(μ-SCH2CH2S)] and [{(μ-H)M3(CO)10)}2(μ-SCH2CH2CH2S)] (M = Ru, Os)

A comparison between the reactivity of [Ru-3(CO)(12)] and [Os-3(CO)(10)(MeCN)(2)] with 1,2-ethanedithiol (HSCH2CH2SH) and 1,3-propanedithiol (HSCH2CH2CH2SH) is reported. The reaction of [Ru-3(CO)(12)] with 1.2-ethanedithiol at 68 degrees C afforded [Ru-2(CO)(6)(mu-SCH2CH2S)] (1) in 40% yield, whereas the reaction with 1,3-propanedithiol yielded [{(mu-H)Ru-3(CO)(10)}(2)(mu-SCH2CH2CH2S)] (2) and [Ru-2(CO)(6)(mu-SCH2CH2CH2S)] (3) in 30 and 19% yields respectively. Treatment of [Os-3(CO)(10)(MeCN)(2)] with 1,2-ethanedithiol gave [(mu-H) Os-3(CO)(10)(mu-SCH2CH2SH)] (4) in 60% yield and with 1,3-propanedithiol it afforded [{(mu-H)Os-3(CO)(10)}(2)(mu-SCH2CH2CH2S)] (5) in 30% yield. Compounds 1 and 3 both react with equimolar amounts of PPh3 at room temperature to give the monosubstituted products [Ru-2(CO)(5)(mu-SCH2CH2S)(PPh3)] (6) and [Ru-2(CO)(5)(mu-SCH2CH2S)(PPh3)] (7) respectively. When heated to 68 degrees C, compound 2 transformed into 3. The compounds have been characterized by spectroscopic studies, and in the case of 1, 2 and 5 by X-ray crystallography. (C) 2000 Elsevier Science Ltd All rights reserved.