Dichloridotetrakis dimethylsulfoxide ruthenium II

62 for free dmso). The extent of the hydrolysis depends on the concentration of the complex and on the content of adventitious water. This feature is often confusing, and wrongly suggests the presence of by-products in the original sample. 

A 100-mL round-bottomed flask equipped with a condenser and a magnetic stirring bar is charged with cw-[RuCl2(dmso)4] (2.50g, 5.16 mmol) suspended in DMSO (40 mL). The mixture is stirred and warmed to 80°C until complete dissolution of the yellow solid (ca. 30 min). The yellow solution is transferred into a water-cooled photoreactor equipped with 125-W mercury lamp and is irradiated for 4h. During this time, the temperature is maintained at ca. 25°C. The same reaction can also be performed under direct sunlight, but requires typically at least 6 h. The deep yellow microcrystalline precipitate is filtered, washed with DMSO (2mL) and acetone (3 x 5mL),and vacuum dried atroom temperature. Yield 2.00g(4.13mmol, 80%). 

SYNTHESIS OF CIILORIDE-FREE RUTHENIUM(H) HEXAAQUA TOSYLATE, [Ru(H20)6]tos2 

Submitted by CELINE FELLAY and GABOR LAURENCZY Checked by STEVEN M. BISCHOF1 and ROY A. PERIANA1  

All manipulations are performed under argon atmosphere using standard Schlenk techniques. All solutions are degassed with argon prior to use. 

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