Triosmium and triruthenium clusters containing deprotonated 2-mercapto-1-methylimidazole ligand:: X-ray structures of [(μ-H)OS3(CO)10{μ-SC=NCH=CHN(CH3)}], [(μ-H)Ru3(CO)9{(μ3-η2-SC=NCH=CHN(CH3)}] and [(μ-H)Os3(CO)8{μ-SC=NCH=CHN(CH3)}μ-dppm)]

The reactions of [Os-3(CO)(10)(MeCN)(2)], [Ru-3(CO)(12]), [(mu-H)Os-3(CO)(8){Ph2PCH2P(Ph)C6H4}], [Os-3(CO)(10)(mu-dppm)] and [Ru-3(CO)(10)(mu-dppm)] with 2-mercapto-1-methylimidazole are reported. The labile cluster [Os-3(Co)(10)(MeCN)(2)] reacts with 2-mercapto-1-methylimidazole at 25 degreesC to give [(mu-H)Os-3(CO)(10){mu-SC=NCH=CHN(CH3)] (1) whereas the corresponding reaction of [Ru-3(CO)(12)] with the ligand at 68 degreesC gives [(mu-H)Ru-3(CO)(9){mu(3)-eta(2)-SC =NCH=CHN(CH3)}] (2). Both [(mu-pH)Os-3(CO)(8){Ph2PCH2P(Ph)C6H4}] and [Os-3 (CO)(10)(mu-dppm)] react with 2-mereapto-1-methylimidazole at 25 and 110 degreesC, respectively, to give [(mu-H)Os-3(CO)(8){mu-SC=NCH=CHN(CH3)(mu-dppm)] (3). In contrast [Ru-3(CO)(10)(mu-dppm) reacts with 2-mercapto-1-methylimidazole at 68 degreesC to yield the known compound [Ru-3(CO)(7)(mu(3)-CO)(mu(3)-S)(mu-dppm)] (4). The structures of 1-3 have been determined by X-ray crystallography. (C) 2002 Elsevier Science Ltd. All rights reserved.